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Sample records for selective antimicrobial action

  1. The antimicrobial polymer PHMB enters cells and selectively condenses bacterial chromosomes

    DEFF Research Database (Denmark)

    Chindera, Kantaraja; Mahato, Manohar; Sharma, Ashwani Kumar

    2016-01-01

    To combat infection and antimicrobial resistance, it is helpful to elucidate drug mechanism(s) of action. Here we examined how the widely used antimicrobial polyhexamethylene biguanide (PHMB) kills bacteria selectively over host cells. Contrary to the accepted model of microbial membrane disrupti...... to bacterial and mammalian cellular DNA and selectively binds and condenses bacterial chromosomes. Because acquired resistance to PHMB has not been reported, selective chromosome condensation provides an unanticipated paradigm for antimicrobial action that may not succumb to resistance....

  2. Antimicrobial action of purified raspberry flavonoid

    African Journals Online (AJOL)

    user

    2012-02-07

    Feb 7, 2012 ... numerous research groups have sought to elucidate the antibacterial mechanisms of action of selected flavonoids. *Corresponding author. E-mail: bdsunjinxu@163.com. (Cushnie et al., 2005), but there have been no reports on the bacteriostatic and bactericidal action of raspberry flavonoid. In this paper ...

  3. Design and mechanism of action of a novel bacteria-selective antimicrobial peptide from the cell-penetrating peptide Pep-1

    International Nuclear Information System (INIS)

    Zhu, W.L.; Lan Hongliang; Park, Il-Seon; Kim, Jae Il; Jin, H.Z.; Hahm, Kyung-Soo; Shin, S.Y.

    2006-01-01

    Here, we report the successful design of a novel bacteria-selective antimicrobial peptide, Pep-1-K (KKTWWKTWWTKWSQPKKKRKV). Pep-1-K was designed by replacing Glu-2, Glu-6, and Glu-11 in the cell-penetrating peptide Pep-1 with Lys. Pep-1-K showed strong antibacterial activity against reference strains (MIC = 1-2 μM) of Gram-positive and Gram-negative bacteria as well as against clinical isolates (MIC = 1-8 μM) of methicillin-resistant Staphylococcus aureus and multidrug-resistant Pseudomonas aeruginosa. In contrast, Pep-1-K did not cause hemolysis of human erythrocytes even at 200 μM. These results indicate that Pep-1-K may be a good candidate for antimicrobial drug development, especially as a topical agent against antibiotic-resistant microorganisms. Tryptophan fluorescence studies indicated that the lack of hemolytic activity of Pep-1-K correlated with its weak ability to penetrate zwitterionic phosphatidylcholine/cholesterol (10:1, w/w) vesicles, which mimic eukaryotic membranes. Furthermore, Pep-1-K caused little or no dye leakage from negatively charged phosphatidylethanolamine/phosphatidylglycerol (7:3, w/w) vesicles, which mimic bacterial membranes but had a potent ability to cause depolarization of the cytoplasmic membrane potential of intact S. aureus cells. These results suggested that Pep-1-K kills microorganisms by not the membrane-disrupting mode but the formation of small channels that permit transit of ions or protons but not molecules as large as calcein

  4. Antimicrobial compounds targeting Gram-negative bacteria in food: Their mode of action and combinational effects

    DEFF Research Database (Denmark)

    Hyldgaard, Morten

    2015-01-01

    compromising food shelf-life or safety. Natural antimicrobial compounds have therefore gained increased interest as a label-friendly alternative that can be added directly to food products. Although natural antimicrobials constitute an interesting source of compounds, it is often not understood how...... they interact with bacterial cells to exert their mechanism of inhibition or killing. Furthermore, natural antimicrobials are often not potent enough as single compounds, and may cause unwanted sensory side-effects, which limit the quantities that can be applied to food. These problems might be circumvented...... by combining antimicrobials to decrease the concentrations needed without compromising their antimicrobial activity. The work described in this dissertation presents two projects concerning the mechanism of action of selected natural antimicrobial compounds primarily against Gram-negative bacteria, and two...

  5. Antimicrobial activity of GN peptides and their mode of action

    DEFF Research Database (Denmark)

    Mojsoska, Biljana; Nielsen, Hanne Mørck; Jenssen, Håvard

    2016-01-01

    peptides due to their characteristics as naturally derived compounds with antimicrobial activity. In this study, we aimed at characterizing the mechanism of action of a small set of in silico optimized peptides. Following determination of peptide activity against E. coli, S. aureus, and P. aeruginosa......Increasing prevalence of bacteria that carries resistance towards conventional antibiotics has prompted the investigation into new compounds for bacterial intervention to ensure efficient infection control in the future. One group of potential lead structures for antibiotics is antimicrobial...

  6. Mechanistic Basis of Antimicrobial Action of Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Tikam Chand Dakal

    2016-11-01

    Full Text Available Multidrug resistance of the pathogenic microorganisms to the antimicrobial drugs has become a major impediment toward successful diagnosis and management of infectious diseases. Recent advancements in nanotechnology-based medicines have opened new horizons for combating multidrug resistance in microorganisms. In particular, the use of silver nanoparticles (AgNPs as a potent antibacterial agent has received much attention. The most critical physico-chemical parameters that affect the antimicrobial potential of AgNPs include size, shape, surface charge, concentration and colloidal state. AgNPs exhibits their antimicrobial potential through multifaceted mechanisms. AgNPs adhesion to microbial cells, penetration inside the cells, ROS and free radical generation, and modulation of microbial signal transduction pathways have been recognized as the most prominent modes of antimicrobial action. On the other side, AgNPs exposure to human cells induces cytotoxicity, genotoxicity and inflammatory response in human cells in a cell-type dependent manner. This has raised concerns regarding use of AgNPs in therapeutics and drug delivery. We have summarized the emerging endeavors that address current challenges in relation to safe use of AgNPs in therapeutics and drug delivery platforms. Based on research done so far, we believe that AgNPs can be engineered so as to increase their efficacy, stability, specificity, biosafety and biocompatibility. In this regard, three perspectives research directions have been suggested that include 1 synthesizing AgNPs with controlled physico-chemical properties, 2 examining microbial development of resistance towards AgNPs, and 3 ascertaining the susceptibility of cytoxicity, genotoxicity, and inflammatory response to human cells upon AgNPs exposure.

  7. Acute and substantive action of antimicrobial toothpastes and mouthrinses on oral biofilm in vitro

    NARCIS (Netherlands)

    Otten, Marieke P. T.; Busscher, Henk J.; van der Mei, Henny C.; van Hoogmoed, Chris G.; Abbas, Frank; Hoogmoed, G.G. van

    The aim of this study was to compare acute action by killing or disrupting oral biofilms through the use of antimicrobial toothpastes and mouthrinses in vitro and to investigate substantive action by absorption of antimicrobials in a biofilm. Biofilms from freshly collected human saliva were grown

  8. Clemastine as Antimicrobial Agent: Effectiveness and Mechanism of Action

    Directory of Open Access Journals (Sweden)

    S.Fazli Bazaz

    1991-07-01

    Full Text Available In this investigation, the antimicrobial activity of Clemastine was studied.The Minimum Inhibitory Concentrations (MICs of this drug against some bacteria were determined using tube dilution method.To find out the bactericidal activity of Clemastine, the number of living bacteria in the presence of drug was counted by a culture method (pour plate method. Thereafter, the preservative effectiveness of Clemastine was studied in detail using standard method (USP 1985.The results show a good antibacterial but not antifungal activity."nIn considering the mechanism of action of Clemastine, it can be seen that the drug has some effect on cell membrane permeability and causes leakage of intracellular material including the K+ .Comparing the bactericidal results with the leakage of K+, shows that the leakage may be due to the bactericidal activity of the drug.

  9. Selective algicidal action of peptides against harmful algal bloom species.

    Directory of Open Access Journals (Sweden)

    Seong-Cheol Park

    Full Text Available Recently, harmful algal bloom (HAB, also termed "red tide", has been recognized as a serious problem in marine environments according to climate changes worldwide. Many novel materials or methods to prevent HAB have not yet been employed except for clay dispersion, in which can the resulting sedimentation on the seafloor can also cause alteration in marine ecology or secondary environmental pollution. In the current study, we investigated that antimicrobial peptide have a potential in controlling HAB without cytotoxicity to harmless marine organisms. Here, antimicrobial peptides are proposed as new algicidal compounds in combating HAB cells. HPA3 and HPA3NT3 peptides which exert potent antimicrobial activity via pore forming action in plasma membrane showed that HPA3NT3 reduced the motility of algal cells, disrupted their plasma membrane, and induced the efflux of intracellular components. Against raphidoflagellate such as Heterosigma akashiwo, Chattonella sp., and C. marina, it displayed a rapid lysing action in cell membranes at 1~4 µM within 2 min. Comparatively, its lysing effects occurred at 8 µM within 1 h in dinoflagellate such as Cochlodium polykrikoides, Prorocentrum micans, and P. minimum. Moreover, its lysing action induced the lysis of chloroplasts and loss of chlorophyll a. In the contrary, this peptide was not effective against Skeletonema costatum, harmless algal cell, even at 256 µM, moreover, it killed only H. akashiwo or C. marina in co-cultivation with S. costatum, indicating to its selective algicidal activity between harmful and harmless algal cells. The peptide was non-hemolytic against red blood cells of Sebastes schlegeli, the black rockfish, at 120 µM. HAB cells were quickly and selectively lysed following treatment of antimicrobial peptides without cytotoxicity to harmless marine organisms. Thus, the antibiotic peptides examined in our study appear to have much potential in effectively controlling HAB with minimal

  10. Antimicrobial peptides with selective antitumor mechanisms: prospect for anticancer applications.

    Science.gov (United States)

    Deslouches, Berthony; Di, Y Peter

    2017-07-11

    In the last several decades, there have been significant advances in anticancer therapy. However, the development of resistance to cancer drugs and the lack of specificity related to actively dividing cells leading to toxic side effects have undermined these achievements. As a result, there is considerable interest in alternative drugs with novel antitumor mechanisms. In addition to the recent approach using immunotherapy, an effective but much cheaper therapeutic option of pharmaceutical drugs would still provide the best choice for cancer patients as the first line treatment. Ribosomally synthesized cationic antimicrobial peptides (AMPs) or host defense peptides (HDP) display broad-spectrum activity against bacteria based on electrostatic interactions with negatively charged lipids on the bacterial surface. Because of increased proportions of phosphatidylserine (negatively charged) on the surface of cancer cells compared to normal cells, cationic amphipathic peptides could be an effective source of anticancer agents that are both selective and refractory to current resistance mechanisms. We reviewed herein the prospect for AMP application to cancer treatment, with a focus on modes of action of cationic AMPs.

  11. Raman spectroscopy, electronic microscopy and SPME-GC-MS to elucidate the mode of action of a new antimicrobial food packaging material.

    Science.gov (United States)

    Clemente, Isabel; Aznar, Margarita; Salafranca, Jesús; Nerín, Cristina

    2017-02-01

    One critical challenge when developing a new antimicrobial packaging material is to demonstrate the mode of action of the antimicrobials incorporated into the packaging. For this task, several analytical techniques as well as microbiology are required. In this work, the antimicrobial properties of benzyl isothiocyanate, allyl isothiocyanate and essential oils of cinnamon and oregano against several moulds and bacteria have been evaluated. Benzyl isothiocyanate showed the highest antimicrobial activity and it was selected for developing the new active packaging material. Scanning electron microscopy and Raman spectroscopy were successfully used to demonstrate the mode of action of benzyl isothiocyanate on Escherichia coli. Bacteria exhibited external modifications such as oval shape and the presence of septum surface, but they did not show any disruption or membrane damage. To provide data on the in vitro action of benzyl isothiocyanate and the presence of inhibition halos, the transfer mechanism to the cells was assessed using solid-phase microextraction-gas chromatography-mass spectrometry. Based on the transfer system, action mechanism and its stronger antimicrobial activity, benzyl isothiocyanate was incorporated to two kinds of antimicrobial labels. The labels were stable and active for 140 days against two mould producers of ochratoxin A; Penicillium verrucosum is more sensitive than Aspergillus ochraceus. Details about the analytical techniques and the results obtained are shown and discussed. Graphical Abstract Antimicrobial evaluation of pure compounds, incorporation in the packaging and study for mode of action on S. coli by Raman, SEM and SPME-GC-MS.

  12. ANTIMICROBIAL ACTION OF THE LEAF EXTRACT OF MORINGA OLEIFERA LAM.

    Science.gov (United States)

    Pal, Saroj K.; Mukherjee, Pulok K.; Saha, Kakali; Pal, M.; Saha, B.P.

    1995-01-01

    The ethnolic extract of the leaves of Moringa oleifera Lam. (Fam. Moringaceae) was tested for antimicrobial activities against Gram Positive – Bacillus cereus, Bacillus subtilis Staphylococcus aureus, Sarcina lutea: Gram negative – Escherichia coli and Acid fast Mycobacterium phlei. Significant antimicrobial activity of the extract was found in this study. PMID:22556699

  13. Antimicrobial susceptibility profile of selected bacteraemic ...

    African Journals Online (AJOL)

    Extended-spectrum 13-lactamase (ESBL) production was determined in selected species of Enterobacteriaceae irrespective of source. Results. The overall prevalence of ampicillin resistance in blood culture isolates of E. coli (N = 471) was 84%, and 20% were resistant to the fluoroquinolones. Considerable geographical ...

  14. Mechanisms underlying selecting objects for action

    Directory of Open Access Journals (Sweden)

    Melanie eWulff

    2015-04-01

    Full Text Available We assessed the factors which affect the selection of objects for action, focusing on the role of action knowledge and its modulation by distracters. 14 neuropsychological patients and 10 healthy aged-matched controls selected pairs of objects commonly used together among distracters in two contexts: with real objects and with pictures of the same objects presented sequentially on a computer screen. Across both tasks, semantically related distracters led to slower responses and more errors than unrelated distracters and the object actively used for action was selected prior to the object that would be passively held during the action. We identified a sub-group of patients (N=6 whose accuracy was 2SD below the controls performances in the real object task. Interestingly, these impaired patients were more affected by the presence of unrelated distracters during both tasks than intact patients and healthy controls. Note the impaired had lesions to left parietal, right anterior temporal and bilateral pre-motor regions. We conclude that: (1 motor procedures guide object selection for action, (2 semantic knowledge affects action-based selection, (3 impaired action decision is associated with the inability to ignore distracting information and (4 lesions to either the dorsal or ventral visual stream can lead to deficits in making action decisions. Overall, the data indicate that impairments in everyday tasks can be evaluated using a simulated computer task. The implications for rehabilitation are discussed.

  15. Membrane selectivity and disordering mechanism of antimicrobial peptide protegrin-1

    Science.gov (United States)

    Ishitsuka, Yuji

    Protegrin-1 (PG-1) is a beta-sheet antimicrobial peptide (AMP), a class of peptides innate to various organisms and functions as a defense agent against harmful microorganisms by means of membrane disordering. Characteristic chemical and structural properties of AMPs allow selective interaction against invaders' cell membranes. Despite their enormous biomedical potential, progress towards developing them into therapeutic agents has been hampered by a lack of insight into their mechanism of action. AMP insertion assays using Langmuir monolayers reveal that both electrostatic properties of the lipid head group as well as the packing density of the lipid tail group play important roles in determining the membrane selectivity of AMPs. These results help elucidate how the AMP selectively targets the cell membrane of microorganisms over the cell membrane of the host. In addition, these results also explain the higher hemolytic ability of PG-1 against human red blood cells (RBCs) compared to the hemolytic ability of PG-1 against sheep and pig RBCs. Synchrotron X-ray reflectivity shows that PG-1 penetrates into the lipid layer. Grazing incidence X-ray diffraction and fluorescence microscopy indicate that the insertion of PG-1 disorders tail group packing. Membrane selectivity and insertion location information of AMPs with different primary sequence and secondary structure have been obtained by using a truncated version of PG-1: PC-17, and an alpha-helical AMP, LL-37, respectively. The similarity of the membrane disordering process across these various peptides motivated us to test the membrane disordering effect of molecules designed to mimic these peptides. Peptide-mimics based on meta-phenylene ethynylenes demonstrate similar membrane disordering effects, showing that the potency of AMPs is derived from their overall chemical and structural properties, rather than exact peptide sequence. Atomic force microscopy (AFM) was used to directly image first, the PG-1

  16. Antioxidant and antimicrobial activities of selected medicinal plants from Algeria

    Institute of Scientific and Technical Information of China (English)

    Krimat Soumia; Dob Tahar; Lamari Lynda; Boumeridja Saida; Chelghoum Chabane; Metidji Hafidha

    2014-01-01

    Objective:To evaluate the antioxidant and antimicrobial activity of methanolic extract extracts of selected Algerian medicinal plants. Methods:Antioxidant activity of extracts was evaluated in terms of radical scavenging potential (2,2-diphenyl-1-picrylhydrazyl) and β-carotene bleaching assay. Total phenolic contents and flavonoid contents were also measured. Antimicrobial activity of these plants was examined against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. Results:The values of IC50 ranged from 4.30 μg/mL to 486.6 μg/mL for the DPPH method, while total antioxidant activity using β-carotene/linoleic acid bleaching assay ranged from 17.03%to 86.13%. It was found that Pistacia lentiscus showed the highest antioxidant capacities using DPPH assay (IC50=4.30 μg/mL), while Populus trimula, Origanum glandulosum, Centaurea calcitrapa, Sysimbrium officinalis and Rhamnus alaternus showed the highest percent of total antioxidant activity inβ-carotene/linoleic acid bleaching assay. Total phenolic and flavonoid contents ranged from 3.96 to 259.65 mg GAE/g extract and from 1.13 to 26.84 mg QE/g extract, respectively. The most interesting antimicrobial activity was obtained from Sysimbrium officinalis, Rhamnus alaternus, Origanum glandulosum, Cupressus sempervirens, Pinus halipensis and Centaurea calcitrapa. Conclusions:The results indicated that the plants tested may be potential sources for isolation of natural antioxidant and antimicrobial compounds.

  17. Antimicrobial Stewardship: A Call to Action for Surgeons

    Science.gov (United States)

    Duane, Therese M.; Catena, Fausto; Tessier, Jeffrey M.; Coccolini, Federico; Kao, Lillian S.; De Simone, Belinda; Labricciosa, Francesco M.; May, Addison K.; Ansaloni, Luca; Mazuski, John E.

    2016-01-01

    Abstract Despite current antimicrobial stewardship programs (ASPs) being advocated by infectious disease specialists and discussed by national and international policy makers, ASPs coverage remains limited to only certain hospitals as well as specific service lines within hospitals. The ASPs incorporate a variety of strategies to optimize antimicrobial agent use in the hospital, yet the exact set of interventions essential to ASP success remains unknown. Promotion of ASPs across clinical practice is crucial to their success to ensure standardization of antimicrobial agent use within an institution. To effectively accomplish this standardization, providers who actively engage in antimicrobial agent prescribing should participate in the establishment and support of these programs. Hence, surgeons need to play a major role in these collaborations. Surgeons must be aware that judicious antibiotic utilization is an integral part of any stewardship program and necessary to maximize clinical cure and minimize emergence of antimicrobial resistance. The battle against antibiotic resistance should be fought by all healthcare professionals. If surgeons around the world participate in this global fight and demonstrate awareness of the major problem of antimicrobial resistance, they will be pivotal leaders. If surgeons fail to actively engage and use antibiotics judiciously, they will find themselves deprived of the autonomy to treat their patients. PMID:27828764

  18. Silica-Gentamicin Nanohybrids: Synthesis and Antimicrobial Action

    Directory of Open Access Journals (Sweden)

    Dina Ahmed Mosselhy

    2016-03-01

    Full Text Available Orthopedic applications commonly require the administration of systemic antibiotics. Gentamicin is one of the most commonly used aminoglycosides in the treatment and prophylaxis of infections associated with orthopedic applications, but gentamicin has a short half-life. However, silica nanoparticles (SiO2 NPs can be used as elegant carriers for antibiotics to prolong their release. Our goal is the preparation and characterization of SiO2-gentamicin nanohybrids for their potential antimicrobial administration in orthopedic applications. In vitro gentamicin release profile from the nanohybrids (gentamicin-conjugated SiO2 NPs prepared by the base-catalyzed precipitation exhibited fast release (21.4% during the first 24 h and further extension with 43.9% release during the five-day experiment. Antimicrobial studies of the SiO2-gentamicin nanohybrids versus native SiO2 NPs and free gentamicin were performed against Bacillus subtilis (B. subtilis, Pseudomonas fluorescens (P. fluorescens and Escherichia coli (E. coli. SiO2-gentamicin nanohybrids were most effective against B. subtilis. SiO2 NPs play no antimicrobial role. Parallel antimicrobial studies for the filter-sterilized gentamicin were performed to assess the effect of ultraviolet (UV-irradiation on gentamicin. In summary, the initial fast gentamicin release fits the need for high concentration of antibiotics after orthopedic surgical interventions. Moreover, the extended release justifies the promising antimicrobial administration of the nanohybrids in bone applications.

  19. 76 FR 21907 - Draft Action Plan-A Public Health Action Plan To Combat Antimicrobial Resistance

    Science.gov (United States)

    2011-04-19

    ... Infectious Diseases, Division of Healthcare Quality Promotion, Office of Antimicrobial Resistance, Attn... Promotion, Office of Antimicrobial Resistance; 1600 Clifton Road, NE., Mailstop A-07, Atlanta, Georgia 30333... agencies in addressing antimicrobial resistance (AR) in recognition of the increasing importance of AR as a...

  20. 76 FR 14402 - Draft Action Plan-A Public Health Action Plan To Combat Antimicrobial Resistance

    Science.gov (United States)

    2011-03-16

    ... Infectious Diseases, Division of Healthcare Quality Promotion, Office of Antimicrobial Resistance, Attn... Promotion, Office of Antimicrobial Resistance; 1600 Clifton Road, NE., Mailstop A-07, Atlanta, Georgia 30333... agencies in addressing antimicrobial resistance (AR) in recognition of the increasing importance of AR as a...

  1. Building a Lego wall: Sequential action selection.

    Science.gov (United States)

    Arnold, Amy; Wing, Alan M; Rotshtein, Pia

    2017-05-01

    The present study draws together two distinct lines of enquiry into the selection and control of sequential action: motor sequence production and action selection in everyday tasks. Participants were asked to build 2 different Lego walls. The walls were designed to have hierarchical structures with shared and dissociated colors and spatial components. Participants built 1 wall at a time, under low and high load cognitive states. Selection times for correctly completed trials were measured using 3-dimensional motion tracking. The paradigm enabled precise measurement of the timing of actions, while using real objects to create an end product. The experiment demonstrated that action selection was slowed at decision boundary points, relative to boundaries where no between-wall decision was required. Decision points also affected selection time prior to the actual selection window. Dual-task conditions increased selection errors. Errors mostly occurred at boundaries between chunks and especially when these required decisions. The data support hierarchical control of sequenced behavior. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  2. Antimicrobial Activities and Time-Kill Kinetics of Extracts of Selected Ghanaian Mushrooms

    Directory of Open Access Journals (Sweden)

    Theresa Appiah

    2017-01-01

    Full Text Available The rapid rise of antimicrobial resistance is a worldwide problem. This has necessitated the need to search for new antimicrobial agents. Mushrooms are rich sources of potential antimicrobial agents. This study investigated the antimicrobial properties of methanol extracts of Trametes gibbosa, Trametes elegans, Schizophyllum commune, and Volvariella volvacea. Agar well diffusion, broth microdilution, and time-kill kinetic assays were used to determine the antimicrobial activity of the extracts against selected test organisms. Preliminary mycochemical screening revealed the presence of tannins, flavonoids, triterpenoids, anthraquinones, and alkaloids in the extracts. Methanol extracts of T. gibbosa, T. elegans, S. commune, and V. volvacea showed mean zone of growth inhibition of 10.00±0.0 to 21.50±0.84, 10.00±0.0 to 22.00±1.10, 9.00±0.63 to 21.83±1.17, and 12.00±0.0 to 21.17±1.00 mm, respectively. The minimum inhibitory concentration of methanol extracts of T. gibbosa, T. elegans, S. commune, and V. volvacea ranged from 4.0 to 20, 6.0 to 30.0, 8.0 to 10.0, and 6.0 to 20.0 mg/mL, respectively. Time-kill kinetics studies showed that the extracts possess bacteriostatic action. Methanol extracts of T. gibbosa, T. elegans, S. commune, and V. volvacea exhibited antimicrobial activity and may contain bioactive compounds which may serve as potential antibacterial and antifungal agents.

  3. Role of Antimicrobial Selective Pressure and Secondary Factors on Antimicrobial Resistance Prevalence in Escherichia coli from Food-Producing Animals in Japan

    OpenAIRE

    Harada, Kazuki; Asai, Tetsuo

    2010-01-01

    The use of antimicrobial agents in the veterinary field affects the emergence, prevalence, and dissemination of antimicrobial resistance in bacteria isolated from food-producing animals. To control the emergence, prevalence, and dissemination of antimicrobial resistance, it is necessary to implement appropriate actions based on scientific evidence. In Japan, the Japanese Veterinary Antimicrobial Resistance Monitoring System (JVARM) was established in 1999 to monitor the antimicrobial suscepti...

  4. 76 FR 63927 - Interagency Task Force on Antimicrobial Resistance (ITFAR): An Update on A Public Health Action...

    Science.gov (United States)

    2011-10-14

    ... Task Force on Antimicrobial Resistance (ITFAR): An Update on A Public Health Action Plan to Combat... outlined in A Public Health Action Plan to Combat Antimicrobial Resistance (Action Plan) and solicit... (AR) in recognition of the increasing importance of AR as a public health threat. The Task Force is co...

  5. Comparative synthesis and antimicrobial action of silver nanoparticles and silver nitrate

    Science.gov (United States)

    Mosselhy, Dina A.; El-Aziz, Mohamed Abd; Hanna, Magdy; Ahmed, Mohamed A.; Husien, Mona M.; Feng, Qingling

    2015-12-01

    The high wave of antibiotic bacterial resistance has addressed an importance for administration of different antibacterial agents, as silver nanoparticles (Ag NPs). However, many investigators still suffer conflict in the mechanistic antimicrobial action of Ag NPs and Ag+ ions. In this regard, our study investigated the comparative antimicrobial action of different sizes of Ag NPs as 8 (nAg1) and 29 (nAg2) nm, in comparison with silver nitrate (AgNO3) against five different bacterial species; Aeromonas hydrophila ( A. hydrophila), Pseudomonas putida ( Ps. putida), Escherichia coli ( E. coli), Staphylococcus aureus ( S. aureus), and Bacillus subtilis ( B. subtilis) using agar diffusion assay and minimum inhibitory concentration (MIC). The key role of the size of nanomaterials was detected, as the smaller Ag NPs (nAg1) showed more antimicrobial action than the larger particles. Transmission electron microscopy (TEM) studies demonstrated the different mechanistic antibacterial actions of Ag NPs and AgNO3. The effect of combining Ag NPs with antibiotics was also investigated. Synergistic effect of combining Ag NPs with ampicillin was detected against S. aureus, in a size-dependent manner as well. To summarize, our results point towards the major role played by the size of Ag NPs in their antimicrobial effects and the different toxic mechanisms of actions induced by Ag NPs and AgNO3.

  6. Comparative synthesis and antimicrobial action of silver nanoparticles and silver nitrate

    International Nuclear Information System (INIS)

    Mosselhy, Dina A.; El-Aziz, Mohamed Abd; Hanna, Magdy; Ahmed, Mohamed A.; Husien, Mona M.; Feng, Qingling

    2015-01-01

    The high wave of antibiotic bacterial resistance has addressed an importance for administration of different antibacterial agents, as silver nanoparticles (Ag NPs). However, many investigators still suffer conflict in the mechanistic antimicrobial action of Ag NPs and Ag + ions. In this regard, our study investigated the comparative antimicrobial action of different sizes of Ag NPs as 8 (nAg1) and 29 (nAg2) nm, in comparison with silver nitrate (AgNO 3 ) against five different bacterial species; Aeromonas hydrophila (A. hydrophila), Pseudomonas putida (Ps. putida), Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Bacillus subtilis (B. subtilis) using agar diffusion assay and minimum inhibitory concentration (MIC). The key role of the size of nanomaterials was detected, as the smaller Ag NPs (nAg1) showed more antimicrobial action than the larger particles. Transmission electron microscopy (TEM) studies demonstrated the different mechanistic antibacterial actions of Ag NPs and AgNO 3 . The effect of combining Ag NPs with antibiotics was also investigated. Synergistic effect of combining Ag NPs with ampicillin was detected against S. aureus, in a size-dependent manner as well. To summarize, our results point towards the major role played by the size of Ag NPs in their antimicrobial effects and the different toxic mechanisms of actions induced by Ag NPs and AgNO 3

  7. Comparative synthesis and antimicrobial action of silver nanoparticles and silver nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Mosselhy, Dina A. [Tsinghua University, State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering (China); El-Aziz, Mohamed Abd; Hanna, Magdy [Cairo University, Department of Fish Diseases and Management, Faculty of Veterinary Medicine (Egypt); Ahmed, Mohamed A. [Cairo University, Material Science Laboratory (1), Physics Department, Faculty of Science (Egypt); Husien, Mona M. [Animal Health Research Institute, Microbiological Unit, Fish Diseases Department (Egypt); Feng, Qingling, E-mail: biomater@mail.tsinghua.edu.cn [Tsinghua University, State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering (China)

    2015-12-15

    The high wave of antibiotic bacterial resistance has addressed an importance for administration of different antibacterial agents, as silver nanoparticles (Ag NPs). However, many investigators still suffer conflict in the mechanistic antimicrobial action of Ag NPs and Ag{sup +} ions. In this regard, our study investigated the comparative antimicrobial action of different sizes of Ag NPs as 8 (nAg1) and 29 (nAg2) nm, in comparison with silver nitrate (AgNO{sub 3}) against five different bacterial species; Aeromonas hydrophila (A. hydrophila), Pseudomonas putida (Ps. putida), Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Bacillus subtilis (B. subtilis) using agar diffusion assay and minimum inhibitory concentration (MIC). The key role of the size of nanomaterials was detected, as the smaller Ag NPs (nAg1) showed more antimicrobial action than the larger particles. Transmission electron microscopy (TEM) studies demonstrated the different mechanistic antibacterial actions of Ag NPs and AgNO{sub 3}. The effect of combining Ag NPs with antibiotics was also investigated. Synergistic effect of combining Ag NPs with ampicillin was detected against S. aureus, in a size-dependent manner as well. To summarize, our results point towards the major role played by the size of Ag NPs in their antimicrobial effects and the different toxic mechanisms of actions induced by Ag NPs and AgNO{sub 3}.

  8. Antimicrobial action of sodium hypochlorite and castor oil solutions for denture cleaning - in vitro evaluation.

    Science.gov (United States)

    Salles, Marcela Moreira; Oliveira, Viviane de Cássia; Souza, Raphael Freitas; Silva, Cláudia Helena Lovato; Paranhos, Helena de Freitas Oliveira

    2015-01-01

    The objective of this in vitro study was to evaluate the antimicrobial action of sodium hypochlorite (0.25% and 0.50%) and 10% castor oil solutions against specific microorganisms, by counting Colony Forming Units (CFU) of clinically important bacteria and Candida species. Acrylic resin specimens (n = 320; Lucitone 550) were obtained from square metal matrices (10 x 10 x 2 mm), sterilized by microwave (650W, for 6 minutes) and contaminated by Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Bacillus subtilis, Escherichia coli, Streptococcus mutans, Enterococcus faecalis and Candida glabrata. The specimens were immersed for 20 minutes in one of the following hygiene solutions (n = 10/each): A - 0.25% Sodium hypochlorite; B - 0.5% Sodium hypochlorite; C - 10% Castor oil solution; and D (Control) - saline. Adhered cells were suspended and inoculated into a selective solid medium (37ºC for 24 h). The Student's t-test (α = 0.05) was performed to compare log10(CFU+1)/mL between Groups C and D. The results showed that sodium hypochlorite (0.25% and 0.5%) completely eliminated all detectable microorganisms. The castor oil solution eliminated B. subtilis and reduced counts for other strains. Differences between C and D were significant (p castor oil solution provided moderate efficacy and performed differently on the tested species, with the strongest effect on B. subtilis and with non-significant action on E. faecalis.

  9. Selection-for-action in visual search.

    Science.gov (United States)

    Hannus, Aave; Cornelissen, Frans W; Lindemann, Oliver; Bekkering, Harold

    2005-01-01

    Grasping an object rather than pointing to it enhances processing of its orientation but not its color. Apparently, visual discrimination is selectively enhanced for a behaviorally relevant feature. In two experiments we investigated the limitations and targets of this bias. Specifically, in Experiment 1 we were interested to find out whether the effect is capacity demanding, therefore we manipulated the set-size of the display. The results indicated a clear cognitive processing capacity requirement, i.e. the magnitude of the effect decreased for a larger set size. Consequently, in Experiment 2, we investigated if the enhancement effect occurs only at the level of behaviorally relevant feature or at a level common to different features. Therefore we manipulated the discriminability of the behaviorally neutral feature (color). Again, results showed that this manipulation influenced the action enhancement of the behaviorally relevant feature. Particularly, the effect of the color manipulation on the action enhancement suggests that the action effect is more likely to bias the competition between different visual features rather than to enhance the processing of the relevant feature. We offer a theoretical account that integrates the action-intention effect within the biased competition model of visual selective attention.

  10. Antimicrobial action of minocycline microspheres versus 810-nm diode laser on human dental plaque microcosm biofilms.

    Science.gov (United States)

    Song, Xiaoqing; Yaskell, Tina; Klepac-Ceraj, Vanja; Lynch, Michael C; Soukos, Nikolaos S

    2014-02-01

    The purpose of this study is to investigate the antimicrobial effects of minocycline hydrochloride microspheres versus infrared light at 810 nm from a diode laser on multispecies oral biofilms in vitro. These biofilms were grown from dental plaque inoculum (oral microcosms) and were obtained from six systemically healthy individuals with generalized chronic periodontitis. Multispecies biofilms were derived using supra- and subgingival plaque samples from mesio-buccal aspects of premolars and molars exhibiting probing depths in the 4- to 5-mm range and 1- to 2-mm attachment loss. Biofilms were developed anaerobically on blood agar surfaces in 96-well plates using a growth medium of prereduced, anaerobically sterilized brain-heart infusion with 2% horse serum. Minocycline HCl 1 mg microspheres were applied on biofilms on days 2 and 5 of their development. Biofilms were also exposed on days 2 and 5 of their growth to 810-nm light for 30 seconds using a power of 0.8 W in a continuous-wave mode. The susceptibility of microorganisms to minocycline or infrared light was evaluated by a colony-forming assay and DNA probe analysis at different time points. At all time points of survival assessment, minocycline was more effective (>2 log10 colony-forming unit reduction) than light treatment (P plaque pathogens to light, and it was not possible after treatment with minocycline due to lack of bacterial growth. The cumulative action of minocycline microspheres on multispecies oral biofilms in vitro led to enhanced killing of microorganisms, whereas a single exposure of light at 810 nm exhibited minimal and non-selective antimicrobial effects.

  11. Photocatalytic properties and selective antimicrobial activity of TiO2(Eu)/CuO nanocomposite

    International Nuclear Information System (INIS)

    Michal, Robert; Dworniczek, Ewa; Caplovicova, Maria; Monfort, Olivier; Lianos, Panagiotis; Caplovic, Lubomir; Plesch, Gustav

    2016-01-01

    Highlights: • Nanocomposites composed of Eu-doped anatase grafted with CuO. • Increase in photocatalytic hydrogen production due to CuO acting as electrons sink. • CuO in composites decreasing the photoinduced total mineralization of phenol. • Selective photoinduced antimicrobial activity against Enterococcus species. - Abstract: TiO 2 (Eu)/CuO nanocomposites were prepared by precipitation method. The anatase nanocrystallites with a size of 26 nm exhibited well crystallized and characteristical dipyramidal morphology and {1 0 1} and {0 0 1} faceting. Transmission electron microscopy photographs with atomic resolution showed that the Eu(III) dopants were bounded on surface of titania. In the composites, the CuO nanocrystals exhibiting a monoclinic tenorite structure with a size in the range from 2 to 5 nm were grafted to the surface of titania. The influence of copper(II) oxide led to distinct selectivity in the photocatalytic and antimicrobial properties of the investigated TiO 2 (Eu)/CuO nanocomposites. While the presence of CuO nanocrystals strongly increased the photocatalytic production of hydrogen by ethanol reforming, it decreased the activity in photoinduced total mineralization of phenol comparing with non-modified TiO 2 (Eu). In investigated TiO 2 (Eu)/CuO powders, the photoinduced antimicrobial activity against membranes of Enterococcus species was influenced by the selective binding of CuO to the surface of the microorganism leading to distinct selectivity in their action. The activity against Enterococcus faecalis was higher than against Enterococcus faecium.

  12. Association between selected antimicrobial resistance genes and antimicrobial exposure in Danish pig farms

    DEFF Research Database (Denmark)

    Birkegård, Anna Camilla; Hisham Beshara Halasa, Tariq; Græsbøll, Kaare

    2017-01-01

    Bacterial antimicrobial resistance (AMR) in pigs is an important public health concern due to its possible transfer to humans. We aimed at quantifying the relationship between the lifetime exposure of antimicrobials and seven antimicrobial resistance genes in Danish slaughter pig farms. AMR gene...... levels were quantified by qPCR of total-community DNA in faecal samples obtained from 681 batches of slaughter pigs. The lifetime exposure to antimicrobials was estimated at batch level for the piglet, weaner, and finisher periods individually for the sampled batches. We showed that the effect...... of antimicrobial exposure on the levels of AMR genes was complex and unique for each individual gene. Several antimicrobial classes had both negative and positive correlations with the AMR genes. From 10-42% of the variation in AMR gene levels could be explained in the final regression models, indicating...

  13. Antimicrobial and anti-Quorum Sensing activities of selected medicinal plants of Ethiopia: Implication for development of potent antimicrobial agents.

    Science.gov (United States)

    Bacha, Ketema; Tariku, Yinebeb; Gebreyesus, Fisseha; Zerihun, Shibru; Mohammed, Ali; Weiland-Bräuer, Nancy; Schmitz, Ruth A; Mulat, Mulugeta

    2016-07-11

    Traditional medicinal plants have been used as an alternative medicine in many parts of the world, including Ethiopia. There are many documented scientific reports on antimicrobial activities of the same. To our knowledge, however, there is no report on the anti-Quorum Sensing (Quorum Quenching, QQ) potential of traditional Ethiopian medicinal plants. As many of the opportunistic pathogenic bacteria depend on Quorum Sensing (QS) systems to coordinate their virulence expression, interference with QS could be a novel approach to control bacterial infections. Thus, the aim of this study was to evaluate selected medicinal plants from Ethiopia for their antimicrobial activities against bacterial and fungal pathogens; and to assess the interference of these plant extracts with QS of bacteria. Antimicrobial activities of plant extracts (oil, resins and crude extracts) were evaluated following standard agar diffusion technique. The minimum inhibitory concentrations (MIC) of potent extracts were determined using 96 well micro-titer plates and optical densities were measured using an ELISA Microplate reader. Interference with Quorum Sensing activities of extracts was determined using the recently established E. coli based reporter strain AI1-QQ.1 and signaling molecule N-(ß-ketocaproyl)-L-homoserine lactone (3-oxo-C6-HSL). Petroleum ether extract of seed of Nigella sativa exhibited the highest activity against both the laboratory isolated Bacillus cereus [inhibition zone (IZ), 44 ± 0.31 mm] and B. cereus ATCC 10987 (IZ, 40 ± 2.33 mm). Similarly, oil extract from mature ripe fruit husk of Aframomum corrorima and mature unripe fruit of A. corrorima revealed promising activities against Candida albicans ATCC 90028 (IZ, 35 ± 1.52 mm) and Staphylococcus aureus DSM 346 (IZ, 25 ± 1.32 mm), respectively. Antimicrobial activities of oil extract from husk of A. corrorima and petroleum ether extract of seed of N. sativa were significantly higher than that of

  14. Photocatalytic properties and selective antimicrobial activity of TiO2(Eu)/CuO nanocomposite

    Science.gov (United States)

    Michal, Robert; Dworniczek, Ewa; Caplovicova, Maria; Monfort, Olivier; Lianos, Panagiotis; Caplovic, Lubomir; Plesch, Gustav

    2016-05-01

    TiO2(Eu)/CuO nanocomposites were prepared by precipitation method. The anatase nanocrystallites with a size of 26 nm exhibited well crystallized and characteristical dipyramidal morphology and {1 0 1} and {0 0 1} faceting. Transmission electron microscopy photographs with atomic resolution showed that the Eu(III) dopants were bounded on surface of titania. In the composites, the CuO nanocrystals exhibiting a monoclinic tenorite structure with a size in the range from 2 to 5 nm were grafted to the surface of titania. The influence of copper(II) oxide led to distinct selectivity in the photocatalytic and antimicrobial properties of the investigated TiO2(Eu)/CuO nanocomposites. While the presence of CuO nanocrystals strongly increased the photocatalytic production of hydrogen by ethanol reforming, it decreased the activity in photoinduced total mineralization of phenol comparing with non-modified TiO2(Eu). In investigated TiO2(Eu)/CuO powders, the photoinduced antimicrobial activity against membranes of Enterococcus species was influenced by the selective binding of CuO to the surface of the microorganism leading to distinct selectivity in their action. The activity against Enterococcus faecalis was higher than against Enterococcus faecium.

  15. Antimicrobial action of the essential oil of Lippia gracilis Schauer

    Directory of Open Access Journals (Sweden)

    Cynthia Cavalcanti de Albuquerque

    2006-07-01

    Full Text Available Antimicrobial activity of the essential oil (EO of Lippia gracilis Schauer over fungi and heliconia endophytic bacteria was evaluated. For the fungi Geotrichum candidum; Trichoderma viride; Torula herbarum; Paecillomyces sp.; Fusicoccum sp.; P. aeruginens; Curvularia lunata; Aspergillus nidulans; A. flavus; and A. niger mycelial discs were inoculated in PDA medium with oil (0; 420; 440; 460; 480 e 500 µL L-1. The inhibition percentage in 420 µL L-1 was 100% for all fungi, except for C. lunata and A. niger, which was 95.58% and 89.40% , respectively. In other experiment, a suspension of the Salmonella choleraceuis-diarizonae, Enterobacter asburiae, Bacillus thuringiensis, B. pumilus, B. cereus, Klebsiella pneumoniae, and E. hormaechei was individually added to the solid NYDA medium dishes. In each dish, wells were drilled in medium and filled with water or EO (420 µL L-1. The diameter of the inhibition halo was assessed. K. pneumoniae was the bacterial species less sensitive and E. hormaechei was the most sensitive.Avaliou-se a atividade antimicrobiana do óleo essencial (OE de Lippia gracilis Schauer sobre fungos contaminantes de laboratórios de cultura de tecidos vegetais e bactérias endofíticas de helicônias. Discos de micélio dos fungos Geotrichum candidum; Trichoderma viride; Torula herbarum; Paecillomyces sp.; Aspergillus nidulans; Fusicoccum sp.; A. flavus; P. aeruginens; Curvularia lunata e A. niger, foram inoculados em meio BDA com óleo (0; 420; 440; 460; 480 e 500 µL L-1. O percentual de inibição em 420 µL L-1 foi de 100% para todos os fungos exceto paraC. lunata and A. niger, o qual foi de 95.58% and 89.40% respectivamente. Em outro experimento, suspensão das espécies Salmonela choleraceuis-diarizonae, Enterobacter asburiae, Bacillus thuringiensis, B. pumilus, Klebsiella pneumoniae, E. hormaechei, Bacillus pumilus, B. cereus, B. pumilus foi individualmente adicionada ao meio NYDA, que foi vertido em placas de Petri e, ap

  16. How and why actions are selected: action selection and the dark room problem

    Directory of Open Access Journals (Sweden)

    Venter Elmarie

    2016-04-01

    Full Text Available In this paper, I examine an evolutionary approach to the action selection problem and illustrate how it helps raise an objection to the predictive processing account. Clark examines the predictive processing account as a theory of brain function that aims to unify perception, action, and cognition, but - despite this aim - fails to consider action selection overtly. He off ers an account of action control with the implication that minimizing prediction error is an imperative of living organisms because, according to the predictive processing account, action is employed to fulfill expectations and reduce prediction error. One way in which this can be achieved is by seeking out the least stimulating environment and staying there (Friston et al. 2012: 2. Bayesian, neuroscientific, and machine learning approaches into a single framework whose overarching principle is the minimization of surprise (or, equivalently, the maximization of expectation. But, most living organisms do not find, and stay in, surprise free environments. This paper explores this objection, also called the “dark room problem”, and examines Clark’s response to the problem. Finally, I recommend that if supplemented with an account of action selection, Clark’s account will avoid the dark room problem.

  17. Temporal dynamics and neural architecture of action selection

    OpenAIRE

    Buc Calderon, Cristian

    2016-01-01

    In this thesis we pitted two views of action selection. On the one hand, a traditional view suggesting that action selection emerges from a sequential process whereby perception, cognition and action proceed serially and are subtended by distinct brain areas. On the other hand, an ecological view (formalized in the affordance competition hypothesis) advocating that action selection stems from the parallel implementation of potential action plans. In parallel, the competition between these act...

  18. Antimicrobial action of sodium hypochlorite and castor oil solutions for denture cleaning – in vitro evaluation

    Directory of Open Access Journals (Sweden)

    Marcela Moreira SALLES

    2015-01-01

    Full Text Available The objective of this in vitro study was to evaluate the antimicrobial action of sodium hypochlorite (0.25% and 0.50% and 10% castor oil solutions against specific microorganisms, by counting Colony Forming Units (CFU of clinically important bacteria and Candida species. Acrylic resin specimens (n = 320; Lucitone 550 were obtained from square metal matrices (10 x 10 x 2 mm, sterilized by microwave (650W, for 6 minutes and contaminated by Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Bacillus subtilis, Escherichia coli, Streptococcus mutans, Enterococcus faecalisand Candida glabrata. The specimens were immersed for 20 minutes in one of the following hygiene solutions (n = 10/each: A – 0.25% Sodium hypochlorite; B – 0.5% Sodium hypochlorite; C – 10% Castor oil solution; and D (Control – saline. Adhered cells were suspended and inoculated into a selective solid medium (37ºC for 24 h. The Student’s t-test (α = 0.05 was performed to compare log10(CFU+1/mL between Groups C and D. The results showed that sodium hypochlorite (0.25% and 0.5% completely eliminated all detectable microorganisms. The castor oil solution eliminatedB. subtilisand reduced counts for other strains. Differences between C and D were significant (p E. faecalis. Both sodium hypochlorite solutions (0.25% and 0.5% were effective in eliminating all microorganisms evaluated, and may be useful as cleaning solutions for complete dentures. The castor oil solution provided moderate efficacy and performed differently on the tested species, with the strongest effect on B. subtilis and with non-significant action on E. faecalis.

  19. Convergent Balancing Selection on an Antimicrobial Peptide in Drosophila.

    Science.gov (United States)

    Unckless, Robert L; Howick, Virginia M; Lazzaro, Brian P

    2016-01-25

    Genes of the immune system often evolve rapidly and adaptively, presumably driven by antagonistic interactions with pathogens [1-4]. Those genes encoding secreted antimicrobial peptides (AMPs), however, have failed to exhibit conventional signatures of strong adaptive evolution, especially in arthropods (e.g., [5, 6]) and often segregate for null alleles and gene deletions [3, 4, 7, 8]. Furthermore, quantitative genetic studies have failed to associate naturally occurring polymorphism in AMP genes with variation in resistance to infection [9-11]. Both the lack of signatures of positive selection in AMPs and lack of association between genotype and immune phenotypes have yielded an interpretation that AMP genes evolve under relaxed evolutionary constraint, with enough functional redundancy that variation in, or even loss of, any particular peptide would have little effect on overall resistance [12, 13]. In stark contrast to the current paradigm, we identified a naturally occurring amino acid polymorphism in the AMP Diptericin that is highly predictive of resistance to bacterial infection in Drosophila melanogaster [13]. The identical amino acid polymorphism arose in parallel in the sister species D. simulans, by independent mutation with equivalent phenotypic effect. Convergent substitutions at the same amino acid residue have evolved at least five times across the Drosophila genus. We hypothesize that the alternative alleles are maintained by balancing selection through context-dependent or fluctuating selection. This pattern of evolution appears to be common in AMPs but is invisible to conventional screens for adaptive evolution that are predicated on elevated rates of amino acid divergence. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Proactive Approach for Safe Use of Antimicrobial Coatings in Healthcare Settings: Opinion of the COST Action Network AMiCI

    Directory of Open Access Journals (Sweden)

    Merja Ahonen

    2017-03-01

    Full Text Available Infections and infectious diseases are considered a major challenge to human health in healthcare units worldwide. This opinion paper was initiated by EU COST Action network AMiCI (AntiMicrobial Coating Innovations and focuses on scientific information essential for weighing the risks and benefits of antimicrobial surfaces in healthcare settings. Particular attention is drawn on nanomaterial-based antimicrobial surfaces in frequently-touched areas in healthcare settings and the potential of these nano-enabled coatings to induce (ecotoxicological hazard and antimicrobial resistance. Possibilities to minimize those risks e.g., at the level of safe-by-design are demonstrated.

  1. ANTIMICROBIAL ACTIVITY OF ROSA CANINA FLOWERS AGAINST SELECTED MICROORGANISMS

    Directory of Open Access Journals (Sweden)

    Katarína Rovná

    2015-02-01

    Full Text Available Rosa canina flowers were screened against various plant pathogenic microbial strains to study the antimicrobial properties of the plant. Ethanolic and methanolic extracts of flowers were screened applying agar well diffusion method against two Gram-negative bacteria including Escherichia coli CCM 3988 and Pseudomonas aeruginosa CCM 1960 and three microscopic filamentous fungi strains Aspergillus niger, Fusarium culmorum and Alternaria alternata, respectively. The best antimicrobial effect of ethanolic extract of Rosa canina flowers was found against Pseudomonas aeruginosa and the best antimicrobial effect of methanolic extract of Rosa canina flowers was found against Escherichia coli.

  2. Rapid Inhibition Profiling in Bacillus subtilis to Identify the Mechanism of Action of New Antimicrobials.

    Science.gov (United States)

    Lamsa, Anne; Lopez-Garrido, Javier; Quach, Diana; Riley, Eammon P; Pogliano, Joe; Pogliano, Kit

    2016-08-19

    Increasing antimicrobial resistance has become a major public health crisis. New antimicrobials with novel mechanisms of action (MOA) are desperately needed. We previously developed a method, bacterial cytological profiling (BCP), which utilizes fluorescence microscopy to rapidly identify the MOA of antimicrobial compounds. BCP is based upon our discovery that cells treated with antibiotics affecting different metabolic pathways generate different cytological signatures, providing quantitative information that can be used to determine a compound's MOA. Here, we describe a system, rapid inhibition profiling (RIP), for creating cytological profiles of new antibiotic targets for which there are currently no chemical inhibitors. RIP consists of the fast, inducible degradation of a target protein followed by BCP. We demonstrate that degrading essential proteins in the major metabolic pathways for DNA replication, transcription, fatty acid biosynthesis, and peptidoglycan biogenesis in Bacillus subtilis rapidly produces cytological profiles closely matching that of antimicrobials targeting the same pathways. Additionally, RIP and antibiotics targeting different steps in fatty acid biosynthesis can be differentiated from each other. We utilize RIP and BCP to show that the antibacterial MOA of four nonsteroidal anti-inflammatory antibiotics differs from that proposed based on in vitro data. RIP is a versatile method that will extend our knowledge of phenotypes associated with inactivating essential bacterial enzymes and thereby allow for screening for molecules that inhibit novel essential targets.

  3. Action of Antimicrobial Copper on Bacteria and Fungi Isolated from Commercial Poultry Hatcheries

    Directory of Open Access Journals (Sweden)

    RFR Depner

    Full Text Available ABSTRACT Since 2008, when the US Environmental Protection Agency (EPA registered copper and its alloys as an antimicrobial agent for contact surfaces, research has demonstrated their antimicrobial activity. The aim of this study was to evaluate the efficacy of antimicrobial copper against bacteria and fungi isolated from commercial poultry hatcheries in order to develop a microbiological control alternative in these environments. Samples were collected from the surfaces of hatcher baskets from two hatcheries. Mesophilic microorganisms and fungi/yeasts were isolated and standardized in concentration of 105 cells/mL. Four copper plates and four stainless steel plates were completely immersed for one minute in bacteria and fungi/yeasts solutions and left to dry for a day at room temperature. Subsequently, samples were collected from the metal plates with the aid of sterile swab and delimiter. These samples were planted onto Plate Count Agar (for mesophilic culture and Sabouraud Dextrose Agar (for fungi and yeast culture and incubated at 36°C for 48 hours and at 25°C for 5-7 days, respectively. After incubation, the colonies recovered from the plates were counted according to IN 62 of the Brazilian Ministry of Agriculture. Almost all contamination was eliminated from the surface of copper plates in a single day, while the stainless steel plates proved to be innocuous to the screened microorganisms. Copper, as a contact surface, proved to have important antimicrobial action on bacteria, fungi and yeasts common to hatcheries.

  4. Silver deposited carboxymethyl chitosan-grafted magnetic nanoparticles as dual action deliverable antimicrobial materials.

    Science.gov (United States)

    Vo, Duc-Thang; Sabrina, Sabrina; Lee, Cheng-Kang

    2017-04-01

    Carboxymethyl chitosan (CMCS) was known to have a much better antimicrobial activity than chitosan due to the increased cationic -NH 3 + groups resulted from the intra- and intermolecular interactions between the carboxyl and amino groups. CMCS was grafted onto the surface of silica coated magnetic nanoparticles (MNPs) to obtain magnetically retrievable and deliverable antimicrobial nanoparticles (MNPs@CMCS). The presence of carboxylate groups in CMCS not only enhanced antimicrobial activity but also enabled Ag ions chelating ability to induce the in situ formation of Ag nanoparticles (AgNPs). The deposition of AgNPs on the surface of MNPs@CMCS could significantly increase its antimicrobial activity against planktonic cells due to the dual action of CMCS and AgNPs. Due to its high magnetism, the as-prepared MNPs@CMCS-Ag could be efficiently delivered into an existing biofilm under the guidance of an applied magnetic field. Without direct contact, the Ag ions and/or radical oxygen species (ROS) released from the deposited Ag nanoparticles could effectively kill the bacteria embedded in the extracellular polymeric substances (EPS) matrix of biofilm. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Mode of Action of Lactoperoxidase as Related to Its Antimicrobial Activity: A Review

    Directory of Open Access Journals (Sweden)

    F. Bafort

    2014-01-01

    Full Text Available Lactoperoxidase is a member of the family of the mammalian heme peroxidases which have a broad spectrum of activity. Their best known effect is their antimicrobial activity that arouses much interest in in vivo and in vitro applications. In this context, the proper use of lactoperoxidase needs a good understanding of its mode of action, of the factors that favor or limit its activity, and of the features and properties of the active molecules. The first part of this review describes briefly the classification of mammalian peroxidases and their role in the human immune system and in host cell damage. The second part summarizes present knowledge on the mode of action of lactoperoxidase, with special focus on the characteristics to be taken into account for in vitro or in vivo antimicrobial use. The last part looks upon the characteristics of the active molecule produced by lactoperoxidase in the presence of thiocyanate and/or iodide with implication(s on its antimicrobial activity.

  6. Novel natural food antimicrobials.

    Science.gov (United States)

    Juneja, Vijay K; Dwivedi, Hari P; Yan, Xianghe

    2012-01-01

    Naturally occurring antimicrobial compounds could be applied as food preservatives to protect food quality and extend the shelf life of foods and beverages. These compounds are naturally produced and isolated from various sources, including plants, animals and microorganisms, in which they constitute part of host defense systems. Many naturally occurring compounds, such as nisin, plant essential oils, and natamycin, have been widely studied and are reported to be effective in their potential role as antimicrobial agents against spoilage and pathogenic microorganisms. Although some of these natural antimicrobials are commercially available and applied in food processing, their efficacy, consumer acceptance and regulation are not well defined. This manuscript reviews natural antimicrobial compounds with reference to their applications in food when applied individually or in combination with other hurdles. It also reviews the mechanism of action of selected natural antimicrobials, factors affecting their antimicrobial activities, and future prospects for use of natural antimicrobials in the food industry.

  7. Antifungal effect and action mechanism of antimicrobial peptide polybia-CP.

    Science.gov (United States)

    Wang, Kairong; Jia, Fengjing; Dang, Wen; Zhao, Yanyan; Zhu, Ranran; Sun, Mengyang; Qiu, Shuai; An, Xiaoping; Ma, Zelin; Zhu, Yuanyuan; Yan, Jiexi; Kong, Ziqing; Yan, Wenjin; Wang, Rui

    2016-01-01

    The incidence of life-threatening invasive fungal infections increased significantly in recent years. However, the antifungal therapeutic options are very limited. Antimicrobial peptides are a class of potential lead chemical for the development of novel antifungal agents. Antimicrobial peptide polybia-CP was purified from the venom of the social wasp Polybia paulista. In this study, we synthesized polybia-CP and determined its antifungal effects against a series of Candidian species. Our results showed that polybia-CP has potent antifungal activity and fungicidal activity against the tested fungal cells with a proposed membrane-active action mode. In addition, polybia-CP could induce the increase of cellular reactive oxygen species production, which would attribute to its antifungal activity. In conclusion, the present study suggests that polybia-CP has potential as an antifungal agent or may offer a new strategy for antifungal therapeutic option. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.

  8. Nanovesicle encapsulation of antimicrobial peptide P34: physicochemical characterization and mode of action on Listeria monocytogenes

    Science.gov (United States)

    da Silva Malheiros, Patrícia; Sant'Anna, Voltaire; Micheletto, Yasmine Miguel Serafini; da Silveira, Nadya Pesce; Brandelli, Adriano

    2011-08-01

    Antimicrobial peptide P34, a substance showing antibacterial activity against pathogenic and food spoilage bacteria, was encapsulated in liposomes prepared from partially purified soybean phosphatidylcholine, and their physicochemical characteristics were evaluated. The antimicrobial activity was estimated by agar diffusion assay using Listeria monocytogenes ATCC 7644 as indicator strain. A concentration of 3,200 AU/mL of P34 was encapsulated in nanovesicles and stocked at 4 °C. No significant difference ( p > 0.05) in the biological activity of free and encapsulated P34 was observed through 24 days. Size and PDI of liposomes, investigated by light scattering analysis, were on average 150 nm and 0.22 respectively. Zeta potential was -27.42 mV. There was no significant change ( p > 0.05) in the physicochemical properties of liposomes during the time of evaluation. The liposomes presented closed spherical morphology as visualized by transmission electron microscopy (TEM). The mode of action of liposome-encapsulated P34 under L. monocytogenes cells was investigated by TEM. Liposomes appeared to adhere but not fuse with the bacterial cell wall, suggesting that the antimicrobial is released from nanovesicles to act against the microorganism. The effect of free and encapsulated P34 was tested against L. monocytogenes, showing that free bacteriocin inhibited the pathogen more quickly than the encapsulated P34. Liposomes prepared with low-cost lipid showed high encapsulation efficiency for a new antimicrobial peptide and were stable during storage. The mode of action against the pathogen L. monocytogenes was characterized.

  9. 77 FR 58143 - Interagency Task Force on Antimicrobial Resistance (ITFAR): An Update of A Public Health Action...

    Science.gov (United States)

    2012-09-19

    ...-2012-0011] Interagency Task Force on Antimicrobial Resistance (ITFAR): An Update of A Public Health...), Department of Health and Human Services (HHS). ACTION: Notice of public meeting and request for comments... Federal agencies in accomplishing activities outlined in ``A Public Health Action Plan to Combat...

  10. Developing an approach to assessing the political feasibility of global collective action and an international agreement on antimicrobial resistance.

    Science.gov (United States)

    Rogers Van Katwyk, Susan; Danik, Marie Évelyne; Pantis, Ioana; Smith, Rachel; Røttingen, John-Arne; Hoffman, Steven J

    2016-01-01

    Antimicrobial resistance (AMR) is a global issue. International trade, travel, agricultural practices, and environmental contamination all make it possible for resistant microbes to cross national borders. Global collective action is needed in the form of an international agreement or other mechanism that brings states together at the negotiation table and commits them to adopt or implement policies to limit the spread of resistant microorganisms. This article describes an approach to assessing whether political and stakeholder interests can align to commit to tackling AMR. Two dimensions affecting political feasibility were selected and compared across 82 countries: 1) states' global influence and 2) self-interest in addressing AMR. World Bank GDP ranking was used as a proxy for global influence, while human antibiotic consumption (10-year percent change) was used as a proxy for self-interest in addressing AMR. We used these data to outline a typology of four country archetypes, and discuss how these archetypes can be used to understand whether a proposed agreement may have sufficient support to be politically feasible. Four types of countries exist within our proposed typology: 1) wealthy countries who have the expertise and financial resources to push for global collective action on AMR, 2) wealthy countries who need to act on AMR, 3) countries who require external assistance to act on AMR, and 4) neutral countries who may support action where applicable. Any international agreement will require substantial support from countries of the first type to lead global action, and from countries of the second type who have large increasing antimicrobial consumption levels. A large number of barriers exist that could derail efforts towards global collective action on AMR; issues of capacity, infrastructure, regulation, and stakeholder interests will need to be addressed in coordination with other actors to achieve an agreement on AMR. Achieving a global agreement on

  11. Preparation and antimicrobial action of three tryptic digested functional molecules of bovine lactoferrin.

    Directory of Open Access Journals (Sweden)

    Nilisha Rastogi

    Full Text Available Lactoferrin is an 80 kDa bilobal, iron binding glycoprotein which is primarily antimicrobial in nature. The hydrolysis of lactoferrin by various proteases in the gut produces several functional fragments of lactoferrin which have varying molecular sizes and properties. Here, bovine lactoferrin has been hydrolyzed by trypsin, the major enzyme present in the gut, to produce three functional molecules of sizes approximately 21 kDa, 38 kDa and 45 kDa. The molecules have been purified using ion exchange and gel filtration chromatography and identified using N-terminal sequencing, which reveals that while the 21 kDa molecule corresponds to the N2 domain (21LF, the 38 kDa represents the whole C-lobe (38LF and the 45 kDa is a portion of N1 domain of N-lobe attached to the C-lobe (45LF. The iron binding and release properties of 21LF, 38LF and 45LF have been studied and compared. The sequence and structure analysis of the portions of the excision sites of LF from various species have been done. The antibacterial properties of these three molecules against bacterial strains, Streptococcus pyogenes, Escherichia coli, Yersinia enterocolitica and Listeria monocytogenes were investigated. The antifungal action of the molecules was also evaluated against Candida albicans. This is the first report on the antimicrobial actions of the trypsin cleaved functional molecules of lactoferrin from any species.

  12. Antimicrobial Peptides: Their Role as Infection-Selective Tracers for Molecular Imaging

    Directory of Open Access Journals (Sweden)

    Thomas Ebenhan

    2014-01-01

    Full Text Available Antimicrobial peptides (AMPs are a heterogeneous class of compounds found in a variety of organisms including humans and, so far, hundreds of these structures have been isolated and characterised. They can be described as natural microbicide, selectively cytotoxic to bacteria, whilst showing minimal cytotoxicity towards the mammalian cells of the host organism. They act by their relatively strong electrostatic attraction to the negatively charged bacterial cells and a relatively weak interaction to the eukaryote host cells. The ability of these peptides to accumulate at sites of infection combined with the minimal host’s cytotoxicity motivated for this review to highlight the role and the usefulness of AMPs for PET with emphasis on their mechanism of action and the different interactions with the bacterial cell. These details are key information for their selective properties. We also describe the strategy, design, and utilization of these peptides as potential radiopharmaceuticals as their combination with nuclear medicine modalities such as SPECT or PET would allow noninvasive whole-body examination for detection of occult infection causing, for example, fever of unknown origin.

  13. Effect of different oral oxytetracycline treatment regimes on selection of antimicrobial resistant coliforms in nursery pigs

    DEFF Research Database (Denmark)

    Fresno, Ana Herrero; Zachariasen, Camilla; Norholm, Nanna

    2017-01-01

    A major concern derived from using antimicrobials in pig production is the development of resistance. This study aimed to assess the impact of selected combinations of oral dose and duration of treatment with oxytetracycline (OTC) on selection of tetracycline resistant (TET-R) coliforms recovered...

  14. Antimicrobial Resistance

    Science.gov (United States)

    ... can prevent and manage antimicrobial resistance. It is collaborating with partners to strengthen the evidence base and ... on the global action plan. WHO has been leading multiple initiatives to address antimicrobial resistance: World Antibiotic ...

  15. Antimicrobial Effects of Psidium Guajava Extract as One Mechanism of its Antidiarrhoeal Action

    Science.gov (United States)

    Lutterodt, G.D.; Ismail, A.; Basheer, R.H.; Baharudin, H. Mohd.

    1999-01-01

    A morphine-like spasmolytic action (not naloxone reversible; involving the inhibition of acetylcholine release) and also effects on the transmural transport of electrolytes (Na+ and K+) and water have been reported as possible modes of the antidiarrhoeal action of polar fractions of Psidium guajava leaf extractives. The objective for this study was to verify if the reported modes of the antidiarrhoeal action should be broadened to include direct antimicrobial actions on some of the more common bacteria known to cause toxin-induced acute diarrhoea. Serial dilutions of a water-soluble, freeze-dried methanolic extract were tested on 10 such organisms, grown separately on nutrient agar plates, to determine the minimum inhibitory concentration (MIC) for each of these bacteria. These included the causative agents for (i) enteric fever (Salmonella typhi, Salmonella paratyphi A, Salmonella paratyphi B and Salmonella paratyphi C), (ii) food poisoning (Salmonella typhimurium and Staphylococcus aureus), (iii) dysentery (Shigella dysenteriae, Shigella flexneri and Shigella sonnei), and (iv) cholera (Vibrio cholerae). The growth of all these organisms was inhibited at the MIC of 10mg/ml of the extract, which is equivalent to 2.5μg/ml of active extractable flavonoids. The most sensitive organisms (MIC = 1mg/ml) were Staphylococcus aureus, Vibrio cholerae and Shigella flexneri. PMID:22589684

  16. Operation of the Selected Local Action Group

    Directory of Open Access Journals (Sweden)

    Lukáš Nevěděl

    2015-01-01

    Full Text Available The main objective of this article is to compare the current operation of elected local action group with the concept of learning regions. This comparison is built on detailed knowledge and understanding of the operation of local action group Podbrnensko citizens’ association (Podbrnensko CA and learning regions in general. The following is assumed: the understanding of community-based processes from the perspective of residents, the important stakeholders who influence the operation of communities or locations. The operation of local action groups is in line with the current concept led by local community development (community led local development, CLLD, which uses elements of the LEADER method. In this method the solution of development problems comes primarily from the inside, not from the outside of the studied territory. The methods used for the collection of empirical data were mostly observation and interviews with all partners involved in LAG (31 people, all mayors in LAG (29 people and 176 people from region, i.e. methods, which result in so called deep data. Between the primary techniques applied in the research are: participant observation, unstructured or semi-structured interviews and public debates.

  17. Antimicrobial, antioxidant activities and chemical composition of selected Thai spices

    Directory of Open Access Journals (Sweden)

    Juraithip Wungsintaweekul

    2010-12-01

    Full Text Available Nine volatile oils and six methanol extracts from Ocimum americanum, O. basilicum, O. sanctum, Citrus hystrix,Alpinia galanga, Curcuma zedoaria, Kaempferia parviflora and Zingiber cassumunar were assessed for antimicrobial andantioxidant activities. The volatile oils and extracts were investigated against eight bacteria and three fungi. The resultsillustrated that O. americanum volatile oil exhibited broad spectrum activity against tested bacteria with the MICs ranging1.4-3.6 mg/ml and Candida spp. with the MICs ranging from 0.5-0.6 mg/ml. The O. sanctum volatile oil showed a considerableactivity against only Candida spp. with the MICs ranging from 0.8-1.4 mg/ml. Interestingly, growth of Mycobacteriumphlei was inhibited by the volatiles of O. americanum, C. hystrix peel, and C. zedoaria with MIC of 1.7, 3.5 and 1.2 mg/ml,respectively. For antioxidant activity evaluation, the methanol extracts of C. hystrix (leaf and peel and K. parviflora hadpotent antioxidant activity by the radical-scavenging DPPH method with IC50 of 24.6, 66.3 and 61.5 mg/ml, respectively.GC-MS analysis revealed the typical chemical profiles of the volatile oils. The major component showed the characteristicsof the volatile oils and was probably responsible for the antimicrobial effect.

  18. Comparative antimicrobial activity and mechanism of action of bovine lactoferricin-derived synthetic peptides.

    Science.gov (United States)

    Liu, Yifan; Han, Feifei; Xie, Yonggang; Wang, Yizhen

    2011-12-01

    Lactoferricin B (LfcinB), a 25 residue peptide derived from the N-terminal of bovine lactoferrin (bLF), causes depolarization of the cytoplasmic membrane in susceptible bacteria. Its mechanism of action, however, still needs to be elucidated. In the present study, synthetic LfcinB (without a disulfide bridge) and LfcinB (C-C; with a disulfide bridge) as well as three derivatives with 15-, 11- and 9-residue peptides were prepared to investigate their antimicrobial nature and mechanisms. The antimicrobial properties were measured via minimum inhibitory concentration (MIC) determinations, killing kinetics assays and synergy testing, and hemolytic activities were assessed by hemoglobin release. Finally, the morphology of peptide-treated bacteria was determined by atomic force microscopy (AFM). We found that there was no difference in MICs between LfcinB and LfcinB (C-C). Among the derivatives, only LfcinB15 maintained nearly the same level as LfcinB, in the MIC range of 16-128 μg/ml, and the MICs of LfcinB11 (64-256 μg/ml) were 4 times more than LfcinB, while LfcinB9 exhibited the lowest antimicrobial activity. When treated at MIC for 1 h, many blebs were formed and holes of various sizes appeared on the cell surface, but the cell still maintained its integrity. This suggested that LfcinB had a major permeability effect on the cytoplasmic membrane of both Gram-positive and Gram-negative bacteria, which also indicated it may be a possible intracellular target. Among the tested antibiotics, aureomycin increased the bactericidal activity of LfcinB against E. coli, S. aureus and P. aeruginosa, but neomycin did not have such an effect. We also found that the combination of cecropin A and LfcinB had synergistic effects against E. coli.

  19. Selection-for-action in visual search

    NARCIS (Netherlands)

    Hannus, A; Cornelissen, FW; Lindemann, O; Bekkering, H

    2005-01-01

    Grasping an object rather than pointing to it enhances processing of its orientation but not its color. Apparently, visual discrimination is selectively enhanced for a behaviorally relevant feature. In two experiments we investigated the limitations and targets of this bias. Specifically, in

  20. Biosynthesis of silver nanoparticles using Sida acuta extract for antimicrobial actions and corrosion inhibition potential.

    Science.gov (United States)

    Idrees, Muhammad; Batool, Saima; Kalsoom, Tanzila; Raina, Sadaf; Sharif, Hafiz Muhammad Adeel; Yasmeen, Summera

    2018-02-12

    Nanotechnology exhibits a multidisciplinary area and gained interests for researchers. Nanoparticles produced via physical and chemical methods affects ecosystem drastically. Green synthesis is the charming technique that is inexpensive and safe for the environment. This study aimed to explore the antibacterial actions of as-synthesized silver nanoparticles (Ag-NPs) against Escherichia coli, Staphylococcus aureus and Streptococcus faecalis. Also, the anti-corrosion actions confirmed that the Ag-NPs proved as good inhibitors. In this way, Ag-NPs were prepared via biosynthesis technique by consuming the ground leaves and stem of 'Sida acuta' as a capping agent. The Ag-NPs were formed by irradiation of the aqueous solution of silver nitrate (AgNO 3 ) with extract of S. acuta stem and leaves. The as-synthesized reaction mixture of Ag-NPs was found to exhibit an absorbance band at 446-447 nm, by an UV/VIS spectrophotometer, which is a characteristic of Ag-NPs due to the surface plasmon resonance absorption band. The X-ray diffraction and transmission electron microscopy (TEM) were used for the confirmation of Ag-NPs' variety dimension, morphology and dispersion. The infrared spectra confirmed the bio-fabrication of the Ag-NPs displayed the existence of conceivable functional groups responsible for the bio-reduction and capping. The antimicrobial actions were measured and the zone of inhibition was compared with standard antibiotics.

  1. Mode of antimicrobial action of vanillin against Escherichia coli, Lactobacillus plantarum and Listeria innocua.

    Science.gov (United States)

    Fitzgerald, D J; Stratford, M; Gasson, M J; Ueckert, J; Bos, A; Narbad, A

    2004-01-01

    To investigate the mode of action of vanillin, the principle flavour component of vanilla, with regard to its antimicrobial activity against Escherichia coli, Lactobacillus plantarum and Listeria innocua. In laboratory media, MICs of 15, 75 and 35 mmol l(-1) vanillin were established for E. coli, Lact. plantarum and L. innocua, respectively. The observed inhibition was found to be bacteriostatic. Exposure to 10-40 mmol l(-1) vanillin inhibited respiration of E. coli and L. innocua. Addition of 50-70 mmol l(-1) vanillin to bacterial cell suspensions of the three organisms led to an increase in the uptake of the nucleic acid stain propidium iodide; however a significant proportion of cells still remained unstained indicating their cytoplasmic membranes were largely intact. Exposure to 50 mmol l(-1) vanillin completely dissipated potassium ion gradients in cultures of Lact. plantarum within 40 min, while partial potassium gradients remained in cultures of E. coli and L. innocua. Furthermore, the addition of 100 mmol l(-1) vanillin to cultures of Lact. plantarum resulted in the loss of pH homeostasis. However, intracellular ATP pools were largely unaffected in E. coli and L. innocua cultures upon exposure to 50 mmol l(-1) vanillin, while ATP production was stimulated in Lact. plantarum cultures. In contrast to the more potent activity of carvacrol, a well studied phenolic flavour compound, the extent of membrane damage caused by vanillin is less severe. Vanillin is primarily a membrane-active compound, resulting in the dissipation of ion gradients and the inhibition of respiration, the extent to which is species-specific. These effects initially do not halt the production of ATP. Understanding the mode of action of natural antimicrobials may facilitate their application as natural food preservatives, particularly for their potential use in preservation systems employing multiple hurdles.

  2. Photocatalytic properties and selective antimicrobial activity of TiO{sub 2}(Eu)/CuO nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Michal, Robert [Department of Inorganic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, 84215 Bratislava (Slovakia); Dworniczek, Ewa [Department of Microbiology, Wroclaw Medical University, 50368 Wroclaw (Poland); Caplovicova, Maria [STU Centre for Nanodiagnostics, Slovak University of Technology, 81243 Bratislava (Slovakia); Monfort, Olivier [Department of Inorganic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, 84215 Bratislava (Slovakia); Lianos, Panagiotis [Department of Chemical Engineering, University of Patras, 26500 Patras (Greece); Caplovic, Lubomir [Institute of Materials Science, Faculty of Materials Science and Technology, Slovak University of Technology, 91724 Trnava (Slovakia); Plesch, Gustav, E-mail: plesch@fns.uniba.sk [Department of Inorganic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, 84215 Bratislava (Slovakia)

    2016-05-15

    Highlights: • Nanocomposites composed of Eu-doped anatase grafted with CuO. • Increase in photocatalytic hydrogen production due to CuO acting as electrons sink. • CuO in composites decreasing the photoinduced total mineralization of phenol. • Selective photoinduced antimicrobial activity against Enterococcus species. - Abstract: TiO{sub 2}(Eu)/CuO nanocomposites were prepared by precipitation method. The anatase nanocrystallites with a size of 26 nm exhibited well crystallized and characteristical dipyramidal morphology and {1 0 1} and {0 0 1} faceting. Transmission electron microscopy photographs with atomic resolution showed that the Eu(III) dopants were bounded on surface of titania. In the composites, the CuO nanocrystals exhibiting a monoclinic tenorite structure with a size in the range from 2 to 5 nm were grafted to the surface of titania. The influence of copper(II) oxide led to distinct selectivity in the photocatalytic and antimicrobial properties of the investigated TiO{sub 2}(Eu)/CuO nanocomposites. While the presence of CuO nanocrystals strongly increased the photocatalytic production of hydrogen by ethanol reforming, it decreased the activity in photoinduced total mineralization of phenol comparing with non-modified TiO{sub 2}(Eu). In investigated TiO{sub 2}(Eu)/CuO powders, the photoinduced antimicrobial activity against membranes of Enterococcus species was influenced by the selective binding of CuO to the surface of the microorganism leading to distinct selectivity in their action. The activity against Enterococcus faecalis was higher than against Enterococcus faecium.

  3. Elucidating Duramycin’s Bacterial Selectivity and Mode of Action on the Bacterial Cell Envelope

    Directory of Open Access Journals (Sweden)

    Sahar Hasim

    2018-02-01

    Full Text Available The use of naturally occurring antimicrobial peptides provides a promising route to selectively target pathogenic agents and to shape microbiome structure. Lantibiotics, such as duramycin, are one class of bacterially produced peptidic natural products that can selectively inhibit the growth of other bacteria. However, despite longstanding characterization efforts, the microbial selectivity and mode of action of duramycin are still obscure. We describe here a suite of biological, chemical, and physical characterizations that shed new light on the selective and mechanistic aspects of duramycin activity. Bacterial screening assays have been performed using duramycin and Populus-derived bacterial isolates to determine species selectivity. Lipidomic profiles of selected resistant and sensitive strains show that the sensitivity of Gram-positive bacteria depends on the presence of phosphatidylethanolamine (PE in the cell membrane. Further the surface and interface morphology were studied by high resolution atomic force microscopy and showed a progression of cellular changes in the cell envelope after treatment with duramycin for the susceptible bacterial strains. Together, these molecular and cellular level analyses provide insight into duramycin’s mode of action and a better understanding of its selectivity.

  4. Activity and action screening of selected disinfectants

    Directory of Open Access Journals (Sweden)

    Kateřina Balharová

    2006-01-01

    Full Text Available This research work is aimed to monitoring of selected disinfectants´activity in operational conditions. Hereby there have been monitored two acidic disinfectants Despon K and Mikasan D, which have had-by their producer-stated different recommended concentration. These solutions were monitored in viewpoint of their activity at different temperature, time of circulation, pH and water hardness. In this work there were measured pH of solutions in unloaded medium to be compared with pH of solutions in loaded medium and this measuring was carried out regularly each week within a one month period. During this period there was also monitored total plate count (TPC, which was stated in the dairy, where samples were taken two-times monthly. It has been found, that the disinfectants Mikasan D and Mikal 94D are effective even by high water hardness.

  5. Comparative activity and mechanism of action of three types of bovine antimicrobial peptides against pathogenic Prototheca spp.

    Science.gov (United States)

    Tomasinsig, Linda; Skerlavaj, Barbara; Scarsini, Michele; Guida, Filomena; Piccinini, Renata; Tossi, Alessandro; Zanetti, Margherita

    2012-02-01

    The yeast-like algae of the genus Prototheca are ubiquitous saprophytes causing infections in immunocompromised patients and granulomatous mastitis in cattle. Few available therapies and the rapid spread of resistant strains worldwide support the need for novel drugs against protothecosis. Host defence antimicrobial peptides inactivate a wide array of pathogens and are a rich source of leads, with the advantage of being largely unaffected by microbial resistance mechanisms. Three structurally diverse bovine peptides [BMAP-28, Bac5 and lingual antimicrobial peptide (LAP)] have thus been tested for their capacity to inactivate Prototheca spp. In minimum inhibitory concentration (MIC) assays, they were all effective in the micromolar range against clinical mastitis isolates as well as a Prototheca wickerhamii reference strain. BMAP-28 sterilized Prototheca cultures within 30-60 min at its MIC, induced cell permeabilization with near 100% release of cellular adenosine triphosphate and resulted in extensive surface blebbing and release of intracellular material as observed by scanning electron microscopy. Bac5 and LAP inactivated Prototheca following 3-6 h incubation at fourfold their MIC and did not result in detectable surface damage despite 70-90% killing, suggesting they act via non-lytic mechanisms. In circular dichroism studies, the conformation of BMAP-28, but not that of Bac5 or LAP, was affected by interaction with liposomes mimicking algal membranes. Our results indicate that BMAP-28, Bac5 and LAP kill Prototheca with distinct potencies, killing kinetics, and modes of action and may be appropriate for protothecal mastitis treatment. In addition, the ability of Bac5 and LAP to act via non-lytic mechanisms may be exploited for the development of target-selective drugs. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.

  6. Antimicrobial Effectiveness of Selected Vranac Wines Against Six ...

    African Journals Online (AJOL)

    glucoside and. Folin - Ciocalteu`s phenol reagent were supplied from Sigma Chemical Co. (St Louis, Mo, USA); used reagents were of analytical quality. Wines samples. Selected Vranac wines from vintage 2009, made from autochthonic Vranac V.

  7. The Influence of Interfering Substances on the Antimicrobial Activity of Selected Quaternary Ammonium Compounds

    Directory of Open Access Journals (Sweden)

    Paula A. Araújo

    2013-01-01

    Full Text Available Standard cleaning processes may not remove all the soiling typically found in food industry, such as carbohydrates, fats, or proteins. Contaminants have a high impact in disinfection as their presence may reduce the activity of disinfectants. The influence of alginic acid, bovine serum albumin, yeast extract, and humic acids was assessed on the antimicrobial activities of benzalkonium chloride and cetyltrimethyl ammonium bromide against Bacillus cereus vegetative cells and Pseudomonas fluorescens. The bacteria (single and consortium were exposed to surfactants (single and combined in the absence and presence of potential disinfection interfering substances. The antimicrobial effects of the surfactants were assessed based on the bacterial respiratory activity measured by oxygen uptake rate due to glucose oxidation. The tested surfactants were efficient against both bacteria (single and consortium with minimum bactericidal concentrations ranging from 3 to 35 mg·L−1. The strongest effect was caused by humic acids that severely quenched antimicrobial action, increasing the minimum bactericidal concentration of the surfactants on P. fluorescens and the consortium. The inclusion of the other interfering substances resulted in mild interferences in the antibacterial activity. This study clearly demonstrates that humic acids should be considered as an antimicrobial interfering substance in the development of disinfection strategies.

  8. Neural bases of selective attention in action video game players

    OpenAIRE

    Bavelier, D; Achtman, RL; Mani, M; Föcker, J

    2011-01-01

    Over the past few years, the very act of playing action video games has been shown to enhance several different aspects of visual selective attention. Yet little is known about the neural mechanisms that mediate such attentional benefits. A review of the aspects of attention enhanced in action game players suggests there are changes in the mechanisms that control attention allocation and its efficiency (Hubert-Wallander et al., 2010). The present study used brain imaging to test this hypothes...

  9. Silver nanoparticles: mechanism of antimicrobial action, synthesis, medical applications, and toxicity effects

    Science.gov (United States)

    Prabhu, Sukumaran; Poulose, Eldho K.

    2012-10-01

    Silver nanoparticles are nanoparticles of silver which are in the range of 1 and 100 nm in size. Silver nanoparticles have unique properties which help in molecular diagnostics, in therapies, as well as in devices that are used in several medical procedures. The major methods used for silver nanoparticle synthesis are the physical and chemical methods. The problem with the chemical and physical methods is that the synthesis is expensive and can also have toxic substances absorbed onto them. To overcome this, the biological method provides a feasible alternative. The major biological systems involved in this are bacteria, fungi, and plant extracts. The major applications of silver nanoparticles in the medical field include diagnostic applications and therapeutic applications. In most of the therapeutic applications, it is the antimicrobial property that is being majorly explored, though the anti-inflammatory property has its fair share of applications. Though silver nanoparticles are rampantly used in many medical procedures and devices as well as in various biological fields, they have their drawbacks due to nanotoxicity. This review provides a comprehensive view on the mechanism of action, production, applications in the medical field, and the health and environmental concerns that are allegedly caused due to these nanoparticles. The focus is on effective and efficient synthesis of silver nanoparticles while exploring their various prospective applications besides trying to understand the current scenario in the debates on the toxicity concerns these nanoparticles pose.

  10. Selective Acylation Enhances Membrane Charge Sensitivity of the Antimicrobial Peptide Mastoparan-X

    DEFF Research Database (Denmark)

    Etzerodt, Thomas Povl; Henriksen, Jonas Rosager; Rasmussen, Palle

    2011-01-01

    and positioning of the peptide in the membrane caused by either PA or OA acylation play a critical role in the fine-tuning of the effective charge of the peptide and thereby the fine-tuning of the peptide's selectivity between neutral and negatively charged lipid membranes. This finding is unique compared...... to previous reports where peptide acylation enhanced membrane affinity but also resulted in impaired selectivity. Our result may provide a method of enhancing selectivity of antimicrobial peptides toward bacterial membranes due to their high negative charge—a finding that should be investigated for other...

  11. pH Dependent Antimicrobial Peptides and Proteins, Their Mechanisms of Action and Potential as Therapeutic Agents

    Directory of Open Access Journals (Sweden)

    Erum Malik

    2016-11-01

    Full Text Available Antimicrobial peptides (AMPs are potent antibiotics of the innate immune system that have been extensively investigated as a potential solution to the global problem of infectious diseases caused by pathogenic microbes. A group of AMPs that are increasingly being reported are those that utilise pH dependent antimicrobial mechanisms, and here we review research into this area. This review shows that these antimicrobial molecules are produced by a diverse spectrum of creatures, including vertebrates and invertebrates, and are primarily cationic, although a number of anionic examples are known. Some of these molecules exhibit high pH optima for their antimicrobial activity but in most cases, these AMPs show activity against microbes that present low pH optima, which reflects the acidic pH generally found at their sites of action, particularly the skin. The modes of action used by these molecules are based on a number of major structure/function relationships, which include metal ion binding, changes to net charge and conformational plasticity, and primarily involve the protonation of histidine, aspartic acid and glutamic acid residues at low pH. The pH dependent activity of pore forming antimicrobial proteins involves mechanisms that generally differ fundamentally to those used by pH dependent AMPs, which can be described by the carpet, toroidal pore and barrel-stave pore models of membrane interaction. A number of pH dependent AMPs and antimicrobial proteins have been developed for medical purposes and have successfully completed clinical trials, including kappacins, LL-37, histatins and lactoferrin, along with a number of their derivatives. Major examples of the therapeutic application of these antimicrobial molecules include wound healing as well as the treatment of multiple cancers and infections due to viruses, bacteria and fungi. In general, these applications involve topical administration, such as the use of mouth washes, cream formulations

  12. Chlorine dioxide is a size-selective antimicrobial agent.

    Directory of Open Access Journals (Sweden)

    Zoltán Noszticzius

    Full Text Available BACKGROUND / AIMS: ClO2, the so-called "ideal biocide", could also be applied as an antiseptic if it was understood why the solution killing microbes rapidly does not cause any harm to humans or to animals. Our aim was to find the source of that selectivity by studying its reaction-diffusion mechanism both theoretically and experimentally. METHODS: ClO2 permeation measurements through protein membranes were performed and the time delay of ClO2 transport due to reaction and diffusion was determined. To calculate ClO2 penetration depths and estimate bacterial killing times, approximate solutions of the reaction-diffusion equation were derived. In these calculations evaporation rates of ClO2 were also measured and taken into account. RESULTS: The rate law of the reaction-diffusion model predicts that the killing time is proportional to the square of the characteristic size (e.g. diameter of a body, thus, small ones will be killed extremely fast. For example, the killing time for a bacterium is on the order of milliseconds in a 300 ppm ClO2 solution. Thus, a few minutes of contact time (limited by the volatility of ClO2 is quite enough to kill all bacteria, but short enough to keep ClO2 penetration into the living tissues of a greater organism safely below 0.1 mm, minimizing cytotoxic effects when applying it as an antiseptic. Additional properties of ClO2, advantageous for an antiseptic, are also discussed. Most importantly, that bacteria are not able to develop resistance against ClO2 as it reacts with biological thiols which play a vital role in all living organisms. CONCLUSION: Selectivity of ClO2 between humans and bacteria is based not on their different biochemistry, but on their different size. We hope initiating clinical applications of this promising local antiseptic.

  13. Antimicrobial activity of methanolic extracts of selected marine macroalgae against some pathogenic microorganisms

    Directory of Open Access Journals (Sweden)

    Ehab Omer Abdalla

    2016-05-01

    Full Text Available Objective: To evaluate the antimicrobial activity of methanolic extracts of six marine macroalgae belonging to green algae (Chlorophyceae, brown algae (Phaeophyceae and the red algae (Rhodophyceae collected from the intertidal area of the Sudanese Red Sea coast near Port Sudan. Methods: Methanol was used for extracting the active principles of the algae and the disc diffusion method was performed to examine the activity and the minimum inhibitory concentration of the samples against four pathogenic bacteria and two fungi. Results: All tested algal extracts exhibited considerable bioactivity and inhibited the growth of all pathogenic microorganisms under investigation. The green alga Caulerpa racemosa produced the maximum inhibition zone (21 mm against Candida albicans while the red alga Laurencia papillosa showed low antimicrobial activity with the minimum inhibition zone of 10 mm against Pseudomonas aeruginosa. The tested algal extracts did not show any special antimicrobial influence on the selected microorganisms when they were considered as Grampositive and Gram-negative bacteria and fungi but the most efficient methanolic extracts in inhibiting microbial growth were those of green macroalgae followed by the brown and the red macroalgae respectively. Conclusions: The study demonstrated that the tested marine macroalgae from Sudanese Red Sea coast may represent a potential and alternative source for secondary metabolites with antimicrobial activity.

  14. Reverse engineering truncations of an antimicrobial peptide dimer to identify the origins of potency and broad spectrum of action.

    Science.gov (United States)

    Anantharaman, Aparna; Sahal, Dinkar

    2010-08-26

    Antimicrobial peptides hold promise against antibiotic resistant pathogens. Here, to find the physicochemical origins of potency and broad spectrum antimicrobial action, we report the structure-activity relationships of synthetic intermediates (peptides A-D) of a potent lysine branched dimeric antibacterial peptide DeltaFd. Our studies show that a tetracationic character in a weak helical fold (peptide C) elicits potent but narrow spectrum antimicrobial activity [Minimum inhibitory concentrations (MICs) E. coli 10 microM, S. aureus>100 microM]. In contrast, a hexacationic character in a strong, amphipathic helix (DeltaFd) confers potent and broad spectrum action [MICs E. coli 2.5 microM, S. aureus 5 microM]. While DeltaFd caused rapid and potent permeabilization of the E. coli membranes, the less helical intermediates (peptides A-D) showed slow and weak to no responses. Two seminal findings that may aid future drug design are (a) at identical helicity, increasing charge enhanced outer membrane permeabilization, and (b) at identical charge, increasing helicity stimulated rate of outer membrane permeabilization and kill kinetics besides enhancing potency leading to broad spectrum action.

  15. Robot soccer action selection based on Q learning

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper researches robot soccer action selection based on Q learning . The robot learn to activate particular behavior given their current situation and reward signal. We adopt neural network to implementations of Q learning for their generalization properties and limited computer memory requirements

  16. Multidisciplinary and multisectoral coalitions as catalysts for action against antimicrobial resistance: Implementation experiences at national and regional levels.

    Science.gov (United States)

    Joshi, Mohan P; Chintu, Chifumbe; Mpundu, Mirfin; Kibuule, Dan; Hazemba, Oliver; Andualem, Tenaw; Embrey, Martha; Phulu, Bayobuya; Gerba, Heran

    2018-03-20

    The multi-faceted complexities of antimicrobial resistance (AMR) require consistent action, a multidisciplinary approach, and long-term political commitment. Building coalitions can amplify stakeholder efforts to carry out effective AMR prevention and control strategies. We have developed and implemented an approach to help local stakeholders kick-start the coalition-building process. The five-step process is to (1) mobilise support, (2) understand the local situation, (3) develop an action plan, (4) implement the plan, and (5) monitor and evaluate. We first piloted the approach in Zambia in 2004, then used the lessons learned to expand it for use in Ethiopia and Namibia and to the regional level through the Ecumenical Pharmaceutical Network [EPN]. Call-to-action declarations and workshops helped promote a shared vision, resulting in the development of national AMR action plans, revision of university curricula to incorporate relevant topics, infection control activities, engagement with journalists from various mass media outlets, and strengthening of drug quality assurance systems. Our experience with the coalition-building approach in Ethiopia, Namibia, Zambia, and with the EPN shows that coalitions can form in a variety of ways with many different stakeholders, including government, academia, and faith-based organisations, to organise actions to preserve the effectiveness of existing antimicrobials and contain AMR.

  17. Inhibitory spectra and modes of antimicrobial action of gallotannins from mango kernels (Mangifera indica L.).

    Science.gov (United States)

    Engels, Christina; Schieber, Andreas; Gänzle, Michael G

    2011-04-01

    This study investigated the antimicrobial activities and modes of action of penta-, hexa-, hepta-, octa-, nona-, and deca-O-galloylglucose (gallotannins) isolated from mango kernels. The MICs and minimum bactericidal concentrations (MBCs) against food-borne bacteria and fungi were determined using a critical dilution assay. Gram-positive bacteria were generally more susceptible to gallotannins than were Gram-negative bacteria. The MICs of gallotannins against Bacillus subtilis, Bacillus cereus, Clostridium botulinum, Campylobacter jejuni, Listeria monocytogenes, and Staphylococcus aureus were 0.2 g liter(-1) or less; enterotoxigenic Escherichia coli and Salmonella enterica were inhibited by 0.5 to 1 g liter(-1), and lactic acid bacteria were resistant. The use of lipopolysaccharide mutants of S. enterica indicated that the outer membrane confers resistance toward gallotannins. Supplementation of LB medium with iron eliminated the inhibitory activity of gallotannins against Staphylococcus aureus, and siderophore-deficient mutants of S. enterica were less resistant toward gallotannins than was the wild-type strain. Hepta-O-galloylglucose sensitized Lactobacillus plantarum TMW1.460 to hop extract, indicating inactivation of hop resistance mechanisms, e.g., the multidrug resistance (MDR) transporter HorA. Carbohydrate metabolism of Lactococcus lactis MG1363, a conditionally respiring organism, was influenced by hepta-O-galloylglucose when grown under aerobic conditions and in the presence of heme but not under anaerobic conditions, indicating that gallotannins influence the respiratory chain. In conclusion, the inhibitory activities of gallotannins are attributable to their strong affinity for iron and likely additionally relate to the inactivation of membrane-bound proteins.

  18. Guanidino groups greatly enhance the action of antimicrobial peptidomimetics against bacterial cytoplasmic membranes

    DEFF Research Database (Denmark)

    Andreev, Konstantin; Bianchi, Christopher; Laursen, Jonas Striegler

    2014-01-01

    Antimicrobial peptides or their synthetic mimics are a promising class of potential new antibiotics. Herein we assess the effect of the type of cationic side chain (i.e., guanidino vs. amino groups) on the membrane perturbing mechanism of antimicrobial α-peptide-β-peptoid chimeras. Langmuir...... of the measurements using an array of techniques, including high-resolution synchrotron surface X-ray scattering, epifluorescence microscopy, and in vitro antimicrobial activity to study the molecular mechanisms of peptidomimetic interaction with bacterial membranes. We found guanidino group-containing chimeras...

  19. Antimicrobial and antibiofilm effects of selected food preservatives against Salmonella spp. isolated from chicken samples.

    Science.gov (United States)

    Er, Buket; Demirhan, Burak; Onurdag, Fatma Kaynak; Ozgacar, Selda Özgen; Oktem, Aysel Bayhan

    2014-03-01

    Salmonella spp. are widespread foodborne pathogens that contaminate egg and poultry meats. Attachment, colonization, as well as biofilm formation capacity of Salmonella spp. on food and contact surfaces of food may cause continuous contamination. Biofilm may play a crucial role in the survival of salmonellae under unfavorable environmental conditions, such as in animal slaughterhouses and processing plants. This could serve as a reservoir compromising food safety and human health. Addition of antimicrobial preservatives extends shelf lives of food products, but even when products are supplemented with adequate amounts of preservatives, it is not always possible to inhibit the microorganisms in a biofilm community. In this study, our aims were i) to determine the minimum inhibitory concentrations (MIC) and minimum biofilm inhibitory concentrations (MBIC) of selected preservatives against planktonic and biofilm forms of Salmonella spp. isolated from chicken samples and Salmonella Typhimurium SL1344 standard strain, ii) to show the differences in the susceptibility patterns of same strains versus the planktonic and biofilm forms to the same preservative agent, and iii) to determine and compare antimicrobial and antibiofilm effects of selected food preservatives against Salmonella spp. For this purpose, Salmonella Typhimurium SL1344 standard strain and 4 Salmonella spp. strains isolated from chicken samples were used. Investigation of antimicrobial and antibiofilm effects of selected food preservatives against Salmonella spp. was done according to Clinical and Laboratory Standards Institute M100-S18 guidelines and BioTimer assay, respectively. As preservative agents, pure ciprofloxacin, sodium nitrite, potassium sorbate, sodium benzoate, methyl paraben, and propyl paraben were selected. As a result, it was determined that MBIC values are greater than the MIC values of the preservatives. This result verified the resistance seen in a biofilm community to food

  20. Veterinarians' attitudes toward antimicrobial use and selective dry cow treatment in the Netherlands.

    Science.gov (United States)

    Scherpenzeel, C G M; Santman-Berends, I M G A; Lam, T J G M

    2018-03-28

    In the Netherlands, regulations have been in place since 2008 to reduce the overall use of antimicrobials to mitigate antimicrobial resistance. As part of these regulations, a ban on the preventive use of antimicrobials, such as applying blanket dry cow treatment, was introduced and alternative measures such as selective dry cow treatment (SDCT) were implemented. Both farmers and veterinarians play an important role in implementing these measures and have a shared responsibility with respect to prudent antimicrobial use (AMU). The attitude of Dutch dairy veterinarians toward restricted AMU and toward SDCT is unknown, but a favorable attitude toward this approach seems crucial for successful implementation. In 2015, an online questionnaire was collected from 181 veterinarians that contained questions with regard to their attitude and behavior toward reduction of AMU and toward SDCT. Descriptive statistics were used to describe the data, and multivariable logistic regression models with a logit link function were applied to evaluate potential associations between veterinarians' attitudes toward AMU and SDCT and the rationale behind their mindset, based on positive and negative aspects of reduction in AMU. The veterinarians were divided into 3 groups based on their opinion on 4 statements with regard to AMU and SDCT: veterinarians with an unfavorable, a neutral, and a favorable attitude toward reduction of AMU and toward SDCT. For the multivariable logistic regression analysis, the first 2 groups were combined and compared with the veterinarians with a favorable attitude. The general attitude of Dutch dairy veterinarians toward reduction of AMU was positive, and most expressed the belief that they can still be a good veterinarian when they prescribe less antimicrobials. Veterinarians indicated they progressively promoted SDCT beginning in 2013. Most veterinarians see the advice they provide to farmers on SDCT as the best possible approach and are convinced that their

  1. Neuronal basis for evaluating selected action in the primate striatum.

    Science.gov (United States)

    Yamada, Hiroshi; Inokawa, Hitoshi; Matsumoto, Naoyuki; Ueda, Yasumasa; Kimura, Minoru

    2011-08-01

    Humans and animals optimize their behavior by evaluating outcomes of individual actions and predicting how much reward the actions will yield. While the estimated values of actions guide choice behavior, the choices are also governed by other behavioral norms, such as rules and strategies. Values, rules and strategies are represented in neuronal activity, and the striatum is one of the best qualified brain loci where these signals meet. To understand the role of the striatum in value- and strategy-based decision-making, we recorded striatal neurons in macaque monkeys performing a behavioral task in which they searched for a reward target by trial-and-error among three alternatives, earned a reward for a target choice, and then earned additional rewards for choosing the same target. This task allowed us to examine whether and how values of targets and strategy, which were defined as negative-then-search and positive-then-repeat (or win-stay-lose-switch), are represented in the striatum. Large subsets of striatal neurons encoded positive and negative outcome feedbacks of individual decisions and actions. Once monkeys made a choice, signals related to chosen actions, their values and search- or repeat-type actions increased and persisted until the outcome feedback appeared. Subsets of neurons exhibited a tonic increase in activity after the search- and repeat-choices following negative and positive feedback in the last trials as the task strategy monkeys adapted. These activity profiles as a heterogeneous representation of decision variables may underlie a part of the process for reinforcement- and strategy-based evaluation of selected actions in the striatum. © 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  2. Off-site protective action selection for nuclear reactor accidents

    International Nuclear Information System (INIS)

    Weerakkody, S.D.

    1986-01-01

    A computer program based upon a model using a rational theoretical basis was developed to select appropriate off-site protective actions during nuclear reactor accidents. The special features of this program include (a) introduction of a precursor concept that uses the history of the accident progression to determine the spectrum of potential accident scenarios and estimates of the likelihoods of each accident scenario; (b) use of statistical decision theory and the concept of entropy of a spectrum to select the appropriate protective actions using either the minimax principle or the Bayes action method; and (c) introduction of methods to quantify evacuation travel risks. In order to illustrate the usefulness of the computer program, it was applied at three stages of the Three Mile Island accident scenario. Quantified non-radiological risks of evaluation have been used to establish dose thresholds below which evacuations are not justified. Using the Poisson analysis for evacuation risks and the absolute L-L BEIR model for radiation risk suggests 330 mrems as a reasonable value for this threshold. The usefulness of the program in developing a technical basis to select the size of the plume exposure pathway emergency planning zone (EPZ) is discussed. Quantified evacuation risks, cost, and the current rationale upon which the EPZ is based, justify an EPZ between 5-10 miles for WASH-1400 source-terms

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

    Directory of Open Access Journals (Sweden)

    Jensen Lars

    2008-09-01

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

  4. Antimicrobial activity and mechanism of action of Nu-3, a protonated modified nucleotide

    Directory of Open Access Journals (Sweden)

    Wang Ming

    2011-01-01

    Full Text Available Abstract Background "Nubiotics" are synthetic oligonucleotides and nucleotides with nuclease-resistant backbones, and are fully protonated for enhanced ability to be taken up by bacterial cells. Nu-3 [butyl-phosphate-5'-thymidine-3'-phosphate-butyl], one of the family members of Nubiotics was efficacious in the treatment of burn-wound infections by Pseudomonas aeruginosa in mice. Subsequent studies revealed that Nu-3 had a favorable toxicological profile for use as a pharmaceutical agent. This study evaluated the antibacterial activity of Nu-3 in vitro and its efficacy as a topical antibiotic. In addition, we investigated the possible mechanisms of Nu-3 action at the levels of DNA synthesis and bacterial membrane changes. Methods Antimicrobial minimum inhibitory concentrations (MIC experiments with Nu-3 and controls were measured against a range of Gram-positive and Gram-negative bacteria, including some hospital isolates according to Clinical and Laboratory Standards Institute (CLSI guidelines. Analysis of the killing kinetics of Nu-3 was also performed against two strains (Staphylococcus aureus cvcc 2248 and Pseudomonas aeruginosa cvcc 5668. The mouse skin suture-wound infection model was used to evaluate the antibacterial activity of Nu-3. We used a 5-Bromo-2'-deoxy-uridine Labeling and Detection Kit III (Roche, Switzerland to analyze DNA replication in bacteria according to the manufacturer's instruction. The BacLight™ Bacterial Membrane Potential Kit (Invitrogen was used to measure the bacterial membrane potential in S. aureus. Results Nu-3 had a wide antibacterial spectrum to Gram-positive, Gram-negative and some resistant bacteria. The MIC values of Nu-3 against all tested MRSA and MSSA were roughly in a same range while MICs of Oxacillin and Vancomycin varied between the bacteria tested. In the mouse model of skin wound infection study, the treatment with 5% Nu-3 glycerine solution also showed comparable therapeutic effects to

  5. Central actions of a novel and selective dopamine antagonist

    International Nuclear Information System (INIS)

    Schulz, D.W.

    1985-01-01

    Receptors for the neurotransmitter dopamine traditionally have been divided into two subgroups: the D 1 class, which is linked to the stimulation of adenylate cyclase-activity, and the D 2 class which is not. There is much evidence suggesting that it is the D 2 class which is not. There is much evidence suggesting that it is the D 2 dopamine receptor that mediates the physiological and behavioral actions of dopamine in the intact animal. However, the benzazepine SCH23390 is a dopamine antagonist which has potent behavioral actions while displaying apparent neurochemical selectivity for the D 1 class of dopamine receptors. The purpose of this dissertation was to (1) confirm and characterize this selectivity, and (2) test certain hypothesis related to possible modes of action of SCH233390. The inhibition of adenylate cyclase by SCH23390 occurred via an action at the dopamine receptor only. A radiolabeled analog of SCH23390 displayed the receptor binding properties of a specific high-affinity ligand, and regional receptor densities were highly correlated with dopamine levels. The subcellular distribution of [ 3 H]-SCH23390 binding did not correspond completely with that of dopamine-stimulated adenylate cyclase. The neurochemical potency of SCH23390 as a D 1 receptor antagonist was preserved following parental administration. A variety of dopamine agonists and antagonists displayed a high correlation between their abilities to compete for [ 3 H]-SCH23390 binding in vitro and to act at an adenylate cyclase-linked receptor. Finally, the relative affinities of dopamine and SCH23390 for both D 1 receptors and [ 3 H]-SCH23390 binding sites were comparable. It is concluded that the behavioral effects of SCH23390 are mediated by actions at D 1 dopamine receptors only, and that the physiological importance of this class of receptors should be reevaluated

  6. Bio-functionalized silver nanoparticles for selective colorimetric sensing of toxic metal ions and antimicrobial studies

    Science.gov (United States)

    Vinod Kumar, V.; Anbarasan, S.; Christena, Lawrence Rene; SaiSubramanian, Nagarajan; Philip Anthony, Savarimuthu

    2014-08-01

    Hibiscus Sabdariffa (Gongura) plant extracts (leaves (HL) and stem (HS) were used for the first time in the green synthesis of bio-functionalized silver nanoparticles (AgNPs). The bio-functionality of AgNPs has been successfully utilized for selective colorimetric sensing of potentially health and environmentally hazardous Hg2+, Cd2+ and Pb2+ metal ions at ppm level in aqueous solution. Importantly, clearly distinguishable colour for all three metal ions was observed. The influence of extract preparation condition and pH were also explored on the formation of AgNPs. Both selectivity and sensitivity differed for AgNPs synthesized from different parts of the plant. Direct correlation between the stability of green synthesized AgNPs at different pH and its antibacterial effects has been established. The selective colorimetric sensing of toxic metal ions and antimicrobial effect of green synthesized AgNPs demonstrated the multifunctional applications of green nanotechnology.

  7. Antimicrobial action of calcium hydroxide-based endodontic sealers after setting, against E. faecalis biofilm

    Directory of Open Access Journals (Sweden)

    Gabriely Cristinni REZENDE

    2016-01-01

    Full Text Available Abstract Enterococcus faecalis are gram positive bacteria that can mostly resist endodontic therapy, inducing persistent infection in the root canal system. Endodontic sealers with antimicrobial activity may help eliminate residual microorganisms that survive endodontic treatment. The present study aimed at comparing the antimicrobial activity of Acroseal, Sealapex and AH Plus endodontic sealers in an in vitro biofilm model. Bovine dentin specimens (144 were prepared, and twelve blocks for each sealer and each experimental time point (2, 7 and 14 days were placed and left in contact with plates containing inoculum of E. faecalis (ATCC 51299, to induce biofilm formation. After 14 days, the samples were transferred to another plate with test sealers and kept at 37°C and 5% CO2 for 2, 7 and 14 days. The specimens without sealers were used as a control for each period. The samples were agitated in a sonicator after each experiment. The suspensions were agitated in a vortex mixer, serially diluted in saline, and triple plated onto m-Enterococcus agar. Colonyforming units were counted, and the data were statistically analyzed using ANOVA, Shapiro-Wilk and Kruskal-Wallis one-way tests (p < 0.05 to determine antimicrobial potential. Sealapex showed significant differences at all the experimental time points, in comparison with all the other groups. AH Plus and Acroseal showed antimicrobial activity only on the 14th experimental day. Neither of the sealers tested were able to completely eliminate the biofilm. Sealapex showed the highest antimicrobial activity in all the experimental periods. The antimicrobial activity of all the sealers analyzed increased over time.

  8. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... how antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will result in the development of resistant strains of bacteria, complicating clinician's efforts to select the appropriate antimicrobial ...

  9. Neural bases of selective attention in action video game players.

    Science.gov (United States)

    Bavelier, D; Achtman, R L; Mani, M; Föcker, J

    2012-05-15

    Over the past few years, the very act of playing action video games has been shown to enhance several different aspects of visual selective attention, yet little is known about the neural mechanisms that mediate such attentional benefits. A review of the aspects of attention enhanced in action game players suggests there are changes in the mechanisms that control attention allocation and its efficiency (Hubert-Wallander, Green, & Bavelier, 2010). The present study used brain imaging to test this hypothesis by comparing attentional network recruitment and distractor processing in action gamers versus non-gamers as attentional demands increased. Moving distractors were found to elicit lesser activation of the visual motion-sensitive area (MT/MST) in gamers as compared to non-gamers, suggestive of a better early filtering of irrelevant information in gamers. As expected, a fronto-parietal network of areas showed greater recruitment as attentional demands increased in non-gamers. In contrast, gamers barely engaged this network as attentional demands increased. This reduced activity in the fronto-parietal network that is hypothesized to control the flexible allocation of top-down attention is compatible with the proposal that action game players may allocate attentional resources more automatically, possibly allowing more efficient early filtering of irrelevant information. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Vanillin selectively modulates the action of antibiotics against resistant bacteria.

    Science.gov (United States)

    Bezerra, Camila Fonseca; Camilo, Cicera Janaine; do Nascimento Silva, Maria Karollyna; de Freitas, Thiago Sampaio; Ribeiro-Filho, Jaime; Coutinho, Henrique Douglas Melo

    2017-12-01

    The treatment of infections caused by microorganisms that are resistant to antibiotics represent one of the main challenges of medicine today, especially due to the inefficacy of long-term drug therapy. In the search for new alternatives to treat these infections, many researchers have been looking for new substances derived from natural products to replace, or be used in combination with conventional antibiotics. Vanillin is a phenolic compound whose antimicrobial activity has been used in the elimination of pathogens present in fruits and vegetables. However, its antibacterial and modulating properties remain to be characterized. Therefore, this work aimed to evaluate the antibacterial activity and analyze the modulator activity of vanillin in association with conventional antibiotics. The antimicrobial activity of vanillin was evaluated using the microdilution method to determine the Minimum Inhibitory Concentration (MIC) Standard strains of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and multi-resistant strains of Escherichia coli 06, Staphylococcus aureus 10, Pseudomonas aeruginosa 24 were used in this study. The antibiotic modulating effect was analyzed by combining vanillin with Norfloxacin, Imipenem, Gentamicin, Erythromycin and Tetracycline against the following multiresistant bacteria strains: Escherichia coli 06, Staphylococcus aureus 10 and Pseudomonas aeruginosa 24. Data were analyzed using the ANOVA test of two tracks followed by the post hoc Bonferroni test. Vanillin presented CIMs ≥1024μg/mL against all tested strains demonstrating that it did not present significant antibacterial activity. However, modulated the activity of gentamicin and imipenem against S. aureus and E. coli, causing a synergistic effect, but did not affect the activity of norfloxacin, tetracycline and erythromycin against these same microorganisms. A synergistic effect was also obtained from the association of vanillin with norfloxacin against P

  11. Participatory action research in antimicrobial stewardship: a novel approach to improving antimicrobial prescribing in hospitals and long-term care facilities

    NARCIS (Netherlands)

    van Buul, L.W.; Sikkens, J.J.; van Agtmael, M.A.; Kramer, M.H.H.; van der Steen, J.T.; Hertogh, C.M.P.M.

    2014-01-01

    It is challenging to change physicians' antimicrobial prescribing behaviour. Although antimicrobial prescribing is determined by contextual (e.g. a lack of guidelines), cultural (e.g. peer practice) and behavioural (e.g. perceived decision making autonomy) factors, most antimicrobial stewardship

  12. Mechanism of action and in vitro activity of short hybrid antimicrobial peptide PV3 against Pseudomonas aeruginosa

    International Nuclear Information System (INIS)

    Memariani, Hamed; Shahbazzadeh, Delavar; Sabatier, Jean-Marc; Memariani, Mojtaba; Karbalaeimahdi, Ali; Bagheri, Kamran Pooshang

    2016-01-01

    Antimicrobial peptides are attractive candidates for developing novel therapeutic agents, since they are lethal to a broad spectrum of pathogens and have a unique low tendency for resistance development. In this study, mechanism of action and in vitro anti-pseudomonal activity of previously designed short hybrid antimicrobial peptide PV3 were investigated. Compared to ceftazidime, PV3 had not only higher antibacterial activity but also faster bactericidal activity. PV3 reduced biofilm biomass and viability of biofilm embedded bacteria in a concentration-dependent manner. Although the antimicrobial activity of PV3 was reduced in Mueller-Hinton broth (MHB) containing human serum, it was still active enough to eradication of bacteria at low concentrations. Compared with standard condition (MHB only), there was no significant decrease in antibacterial activity of PV3 against P. aeruginosa strains under 150 mM NaCl (p = 0.615) and 1 mM MgCl 2 (p = 0.3466). Fluorescence microscopy and field emission scanning electron microscopy further indicated that PV3 killed bacteria by disrupting the cell membrane. Since PV3 has potent anti-pseudomonal activity and has little cytotoxicity in vitro, it seems plausible that the peptide should be further investigated with animal studies to support future pharmacological formulations and potential topical applications. - Highlights: • PV3 killed Pseudomonas aeruginosa by membrane-disrupting mechanism. • PV3 reduced biofilm biomass and viability of biofilm embedded bacteria in a concentration-dependent manner. • Short hybrid antimicrobial peptide PV3 exhibited higher and faster bactericidal activity comparing to ceftazidime.

  13. The antimicrobial peptide nisin Z induces selective toxicity and apoptotic cell death in cultured melanoma cells.

    Science.gov (United States)

    Lewies, Angélique; Wentzel, Johannes Frederik; Miller, Hayley Christy; Du Plessis, Lissinda Hester

    2018-01-01

    Reprogramming of cellular metabolism is now considered one of the hallmarks of cancer. Most malignant cells present with altered energy metabolism which is associated with elevated reactive oxygen species (ROS) generation. This is also evident for melanoma, the leading cause of skin cancer related deaths. Altered mechanisms affecting mitochondrial bioenergetics pose attractive targets for novel anticancer therapies. Antimicrobial peptides have been shown to exhibit selective anticancer activities. In this study, the anti-melanoma potential of the antimicrobial peptide, nisin Z, was evaluated in vitro. Nisin Z was shown to induce selective toxicity in melanoma cells compared to non-malignant keratinocytes. Furthermore, nisin Z was shown to negatively affect the energy metabolism (glycolysis and mitochondrial respiration) of melanoma cells, increase reactive oxygen species generation and cause apoptosis. Results also indicate that nisin Z can decrease the invasion and proliferation of melanoma cells demonstrating its potential use against metastasis associated with melanoma. As nisin Z seems to place a considerable extra burden on the energy metabolism of melanoma cells, combination therapies with known anti-melanoma agents may be effective treatment options. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  14. Hydrophilic Phage-Mimicking Membrane Active Antimicrobials Reveal Nanostructure-Dependent Activity and Selectivity.

    Science.gov (United States)

    Jiang, Yunjiang; Zheng, Wan; Kuang, Liangju; Ma, Hairong; Liang, Hongjun

    2017-09-08

    The prevalent wisdom on developing membrane active antimicrobials (MAAs) is to seek a delicate, yet unquantified, cationic-hydrophobic balance. Inspired by phages that use nanostructured protein devices to invade bacteria efficiently and selectively, we study here the antibiotic role of nanostructures by designing spherical and rod-like polymer molecular brushes (PMBs) that mimic the two basic structural motifs of bacteriophages. Three model PMBs with different well-defined geometries consisting of multiple, identical copies of densely packed poly(4-vinyl-N-methylpyridine iodide) branches are synthesized by controlled/"living" polymerization, reminiscent of the viral structural motifs comprised of multiple copies of protein subunits. We show that, while the individual linear-chain polymer branch that makes up the PMBs is hydrophilic and a weak antimicrobial, amphiphilicity is not a required antibiotic trait once nanostructures come into play. The nanostructured PMBs induce an unusual topological transition of bacterial but not mammalian membranes to form pores. The sizes and shapes of the nanostructures further help define the antibiotic activity and selectivity of the PMBs against different families of bacteria. This study highlights the importance of nanostructures in the design of MAAs with high activity, low toxicity, and target specificity.

  15. Study of in vitro antimicrobial and antiproliferative activities of selected Saharan plants.

    Science.gov (United States)

    Palici, Ionut F; Liktor-Busa, Erika; Zupkó, István; Touzard, Blaise; Chaieb, Mohamed; Urbán, Edit; Hohmann, Judit

    2015-12-01

    The aim of the present study was the evaluation of the antimicrobial and antiproliferative activities of selected Saharan species, which are applied in the traditional medicine but not studied thoroughly from chemical and pharmacological point of view. The studied plants, namely Anthyllis henoniana, Centropodia forskalii, Cornulaca monacantha, Ephedra alata var. alenda, Euphorbia guyoniana, Helianthemum confertum, Henophyton deserti, Moltkiopsis ciliata and Spartidium saharae were collected from remote areas of North Africa, especially from the Tunisian region of Sahara. After drying and applying the appropriate extraction methods, the plant extracts were tested in antimicrobial screening assay, performed on 19 Gram-positive and -negative strains of microbes. The inhibition zones produced by plant extracts were determined by disc-diffusion method. Remarkable antibacterial activities were exhibited by extracts of Ephedra alata var. alenda and Helianthemum confertum against B. subtilis, M. catarrhalis and methicillin-resistant and non-resistant S. aureus. Minimum inhibitory concentrations of these two species were also determined. Antiproliferative effects of the extracts were evaluated against 4 human adherent cell lines (HeLa, A431, A2780 and MCF7). Notable cell growth inhibition was found for extract of Helianthemum confertum and Euphorbia guyoniana. Our results provided data for selection of some plant species for further detailed pharmacological and phytochemical examinations.

  16. Anti-Inflammatory and Antimicrobial Actions of Vitamin D in Combating TB/HIV

    Directory of Open Access Journals (Sweden)

    Anna K. Coussens

    2014-01-01

    Full Text Available Tuberculosis (TB disease activation is now believed to arise due to a lack of inflammatory homeostatic control at either end of the spectrum of inflammation: either due to immunosuppression (decreased antimicrobial activity or due to immune activation (excess/aberrant inflammation. Vitamin D metabolites can increase antimicrobial activity in innate immune cells, which, in the context of HIV-1 coinfection, have insufficient T cell-mediated help to combat Mycobacterium tuberculosis (MTB infection. Moreover, maintaining vitamin D sufficiency prior to MTB infection enhances the innate antimicrobial response to T cell-mediated interferon-γ. Conversely, vitamin D can act to inhibit expression and secretion of a broad range of inflammatory mediators and matrix degrading enzymes driving immunopathology during active TB and antiretroviral- (ARV- mediated immune reconstitution inflammatory syndrome (IRIS. Adjunct vitamin D therapy during treatment of active TB may therefore reduce lung pathology and TB morbidity, accelerate resolution of cavitation and thereby decrease the chance of transmission, improve lung function following therapy, prevent relapse, and prevent IRIS in those initiating ARVs. Future clinical trials of vitamin D for TB prevention and treatment must be designed to detect the most appropriate primary endpoint, which in some cases should be anti-inflammatory and not antimicrobial.

  17. The membrane action mechanism of novel antimicrobial peptide COD isolated from the venom of bee

    Czech Academy of Sciences Publication Activity Database

    Čujová, Sabína; Slaninová, Jiřina; Fučík, Vladimír; Monincová, Lenka; Voburka, Zdeněk; Čeřovský, Václav

    2013-01-01

    Roč. 42, Suppl. 1 (2013), S164-S164 ISSN 0175-7571. [European Biophysics Congress EBSA /9./. 13.07.2013-17.07.2013, Lisbon] Institutional support: RVO:61388963 Keywords : antimicrobial peptides * COD Subject RIV: CC - Organic Chemistry

  18. Identification, purification and elucidation of the mode of action of (novel) antimicrobial substances

    NARCIS (Netherlands)

    Oppedijk, S.F.

    2017-01-01

    Antibiotics are among the most frequently prescribed medications in current medicine, however there is an increasing resistance emerging against our current arsenal of antibiotics. Therefore, it is important that we do research into antimicrobial substances that uniquely work on essential pathways

  19. In vitro evaluation of the root canal cleaning ability of plant extracts and their antimicrobial action

    Directory of Open Access Journals (Sweden)

    Edja Maria Melo de Brito Costa

    2012-06-01

    Full Text Available This in vitro study evaluated both the antimicrobial activity and the root canal cleaning ability of plant extracts used in irrigation solutions. The antimicrobial activities of the aroeira-da-praia (Schinus terebintifolius Raddi and the quixabeira (Syderoxylum obtusifolium Roem & Schult hydroalcoholic extracts, of 2.5% sodium hypochlorite (NaOCl and of 0.12% chlorhexidine (positive control against Enterococcus faecalis were tested with the agar well diffusion method. The level of root canal cleanliness was examined by scanning electron microscopy (SEM. Twenty one single-rooted human teeth were divided into three groups according to the irrigation solution applied: 1 50% aroeira-da-praia; 2 50% quixabeira and 3 a combination of 2.5% sodium hypochlorite + 17% EDTA. All solutions tested demonstrated antimicrobial activity against Enterococcus faecalis. The SEM analysis revealed that higher and lower degrees of surface cleaning were observed, in the three groups, respectively for the coronal and apical thirds, in that quixabeira showed the greatest efficiency in removing the smear layer in the apical third. All the agents tested presented antimicrobial activity against E. faecalis. None, however, was able to completely remove the smear layer of the dentinal surface in the different thirds of the root canal. The results suggest that the analyzed plant extracts may represent a new therapeutic option in the list of alternative agents available for endodontic treatment.

  20. Influence of gamma radiation on molluscicidal and antimicrobial action of leaf and stem bark of Ziziphus joazeiro

    International Nuclear Information System (INIS)

    Mendes, Fabricio O.; Siqueira, Williams N.; Lima, Maira V.; Melo, Larissa S.A.; Luna Filho, Ricardo L.C.; Morais, Vinicius H.T.; Oliveira, Maria L.M.; Melo, Ana M.M.A.; Silva, Edvane B.

    2017-01-01

    Ionizing radiation is a physical agent used in several areas of knowledge: in medicine for the diagnosis and treatment of diseases, in the industry, it is apply in the generation of energy, sterilization of equipment and food, for example. Studies show that radiation can modify the molecular structure of substances of natural origin, potentiating or inactivating their function. The compounds derived from plants have received special attention because they constitute a form of medicinal therapy that has been growing notably in recent years. In addition, products of natural origin may also aid in the control of microbiological or animal vectors of parasites. Of the various species of plants being studied, Ziziphus joazeiro, popularly known as jua, native to the Caatinga, is commercially exploited for the manufacture of cosmetics and as anti-inflammatory, antimicrobial, anti influenza, fever and gastritis, bruises and has molluscicidal activity. Therefore, the objective of this work was to evaluate the influence of cobalt-60 gamma radiation on leaf and bark extracts of Z. joazeiro stem, evaluating possible changes in molluscicidal and antimicrobial action. For the experiments, the Z joazeiro extracts were irradiated with doses of 5, 7.5 and 10 kGy (Gammacell-Cobalt-60, dose rate 7.222 kGy/h). Adult mollusks (n = 60) and embryos (n = 1800) of Biomphalaria glabrata were distributed in the following groups: negative control 1 (water only); negative control 2 (extract only); positive control (CuCO_3); and three groups submitted to irradiated extracts. The antibacterial assay was performed with Gram-positive microorganisms (Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis, Enterococcus faecalis) belonging to the collection of the Departamento de Antibioticos of the UFPE by disc diffusion method. Statistical analysis was perform by Student's t-test and chi-square test, with a confidence interval of 95%. The results showed that the ionizing radiation was not able

  1. Guanidino Groups Greatly Enhance the Action of Antimicrobial Peptidomimetics Against Bacterial Cytoplasmic Membranes

    Science.gov (United States)

    2014-05-28

    permeated is not completely understood, and several models have been proposed based on studies conducted with various peptidic structures [1]. Moreover...approach has been successfully used in conjunction with liquid surface X-ray scattering to study bacterial membrane lysis by human antimicrobial peptide...diluted in MHB pH 7.4 to a final concentration of approx. 5 × 105 CFU/mL in each well. Polypropylene plates (Nunc 442587) were used to minimize peptide

  2. Effectiveness of the actions of antimicrobial's control in the intensive care unit

    Directory of Open Access Journals (Sweden)

    Santos Edilson Floriano dos

    2003-01-01

    Full Text Available There are various strategies to improve the effectiveness of antibiotics in hospitals. In general, the implementation of guidelines for appropriate antibiotic therapy and the participation of infectious disease (ID physicians deserve considerable attention. This study was a prospective ecological time-series study that evaluates the effectiveness of the ID physician's opinion to rationalize and control the use of antibiotics in medical-surgical intensive care units (ICU, and the impact of their intervention on treatment expenditures. There was significant change in the pattern of use of antimicrobials, this pattern approximating that of a medical-surgical ICU that participates in the ICARE (Intensive Care Antimicrobial Resistance Epidemiology Project. For example, there was a significant increase in the consumption of antimicrobials of the ampicillin group (Relative Risk [RR]=3.39; 95% CI: 2.34-4.91 and antipseudomonal penicillins (RR=2.89; 95% CI: 1.70-4.92. On the other hand, there was a significant reduction in the consumption of 3rd/4th generation cephalosporins (RR=0.66; 95% CI: 0.57-0.77 and carbapenems (RR=0.43; 95% CI: 0.33-0.56. On average, for every patient-day antibiotic expense was reduced 37.2% during calendar year 2001, when compared with 2000. The ID specialists' opinion and the adoption of guidelines for empirical antibiotic therapy of hospital-acquired pneumonia contributed to a reduction in the use of antimicrobials in medical-surgical ICU. However, further studies that have more control over confounding variables are needed to help determine the relevance of these discoveries.

  3. Designing, synthesis, and antimicrobial action of oxazoline and thiazoline derivatives of fatty acid esters.

    Science.gov (United States)

    Ahmad, Anis; Ahmad, Aiman; Sudhakar, Raja; Varshney, Himani; Subbarao, Naidu; Ansari, Saba; Rauf, Abdul; Khan, Asad U

    2017-11-01

    In this study, a novel series of oxazoline and thiazoline were designed as inhibitors of cytochrome P450 14 alpha-sterol demethylase (CYP51) from Candida albicans and peptide deformylase (PDF) of Escherichia coli. The long chain dibromo derivative of fatty acid esters on reaction with urea and thiourea gave their corresponding oxazolines and thiazolines, respectively. All the compounds were characterized by their spectral data (IR, 1 H NMR, 13 C NMR and MS) and tested for antibacterial and antifungal activity by disk diffusion assay and minimum inhibitory concentration by the broth microdilution method against gram-positive and gram-negative strains of bacteria as well as fungus strains. The investigation into antimicrobial screening revealed that all the compounds were found to be potent antimicrobial agents. After calculating likeness drug properties of the compounds by Prediction of Activity Spectra for Substances software, ADMET-related descriptors were computed to predict the pharmacokinetic properties for the active and bioavailable compounds by discovery studio 2.5. Molecular docking studies have been performed on PDF of E. coli and CYP 450-14DM of C. albicans to understand the mode of binding of the molecules in the active site of the receptor. Compounds (2-amino-5-(carbomethoxyoctyl)-1,3-oxazoline, 2-amino-5-(carbomethoxyoctyl)-1,3-thiazoline and 2-amino-4-pentyl-5-[(8'R)-8' hydroxy (carbomethoxydecyl)-1,3-oxazoline) showed excellent antimicrobial activity nearly equivalent to the control compounds and compounds, 2-amino-4-octyl-5-(carbomethoxyheptyl)-1,3-oxazolin, 2-amino-4-(2'R)(2'-hydroxy octyl)-5-(carbomethoxyheptyl)-1,3-oxazoline and 2-amino-4-pentyl-5-[(8'R)-8'-hydroxy(carbomethoxy decyl)-1,3-oxazolineshowed vasodilation and antihypertensive properties. Furthermore, a computational analysis of physicochemical parameters revealed that the most of the compounds possessed drug-like attributes. Using Bioinformatics approach, we found a correlation

  4. Effectiveness of the actions of antimicrobial's control in the intensive care unit

    Directory of Open Access Journals (Sweden)

    Edilson Floriano dos Santos

    Full Text Available There are various strategies to improve the effectiveness of antibiotics in hospitals. In general, the implementation of guidelines for appropriate antibiotic therapy and the participation of infectious disease (ID physicians deserve considerable attention. This study was a prospective ecological time-series study that evaluates the effectiveness of the ID physician's opinion to rationalize and control the use of antibiotics in medical-surgical intensive care units (ICU, and the impact of their intervention on treatment expenditures. There was significant change in the pattern of use of antimicrobials, this pattern approximating that of a medical-surgical ICU that participates in the ICARE (Intensive Care Antimicrobial Resistance Epidemiology Project. For example, there was a significant increase in the consumption of antimicrobials of the ampicillin group (Relative Risk [RR]=3.39; 95% CI: 2.34-4.91 and antipseudomonal penicillins (RR=2.89; 95% CI: 1.70-4.92. On the other hand, there was a significant reduction in the consumption of 3rd/4th generation cephalosporins (RR=0.66; 95% CI: 0.57-0.77 and carbapenems (RR=0.43; 95% CI: 0.33-0.56. On average, for every patient-day antibiotic expense was reduced 37.2% during calendar year 2001, when compared with 2000. The ID specialists' opinion and the adoption of guidelines for empirical antibiotic therapy of hospital-acquired pneumonia contributed to a reduction in the use of antimicrobials in medical-surgical ICU. However, further studies that have more control over confounding variables are needed to help determine the relevance of these discoveries.

  5. In Vitro Antimicrobial Activity of Spices and Medicinal Herbs against Selected Microbes Associated with Juices

    Directory of Open Access Journals (Sweden)

    Romika Dhiman

    2016-01-01

    Full Text Available In the present investigation, comparison of antimicrobial activities of different spices, Curcuma longa, Zingiber officinale, and Mentha arvensis, and medicinal herbs, such as Withania somnifera, Rauvolfia serpentina, Emblica officinalis, Terminalia arjuna, and Centella asiatica, was evaluated. Different extraction solvents (acetone, methanol, ethanol, and water were used and extracts were examined against Bacillus cereus, Serratia sp., Rhodotorula mucilaginosa, Aspergillus flavus, and Penicillium citrinum isolated from juices. Extracts from the medicinal herb and spices have significant activity. B. cereus was the most sensitive and R. mucilaginosa was the most resistant among the microorganisms tested. Ethanolic and methanolic extract of C. asiatica displayed maximum diameter of inhibition zone against bacteria and yeast and percentage mycelial inhibition against moulds. This study confirmed the potential of selected extracts of spices as effective natural food preservative in juices.

  6. In Vitro Antimicrobial Activity of Spices and Medicinal Herbs against Selected Microbes Associated with Juices

    Science.gov (United States)

    Dhiman, Romika; Aggarwal, Neeraj; Aneja, Kamal Rai; Kaur, Manpreet

    2016-01-01

    In the present investigation, comparison of antimicrobial activities of different spices, Curcuma longa, Zingiber officinale, and Mentha arvensis, and medicinal herbs, such as Withania somnifera, Rauvolfia serpentina, Emblica officinalis, Terminalia arjuna, and Centella asiatica, was evaluated. Different extraction solvents (acetone, methanol, ethanol, and water) were used and extracts were examined against Bacillus cereus, Serratia sp., Rhodotorula mucilaginosa, Aspergillus flavus, and Penicillium citrinum isolated from juices. Extracts from the medicinal herb and spices have significant activity. B. cereus was the most sensitive and R. mucilaginosa was the most resistant among the microorganisms tested. Ethanolic and methanolic extract of C. asiatica displayed maximum diameter of inhibition zone against bacteria and yeast and percentage mycelial inhibition against moulds. This study confirmed the potential of selected extracts of spices as effective natural food preservative in juices. PMID:26880927

  7. Experimental mixture design as a tool for the synthesis of antimicrobial selective molecularly imprinted monodisperse microbeads.

    Science.gov (United States)

    Benito-Peña, Elena; Navarro-Villoslada, Fernando; Carrasco, Sergio; Jockusch, Steffen; Ottaviani, M Francesca; Moreno-Bondi, Maria C

    2015-05-27

    The effect of the cross-linker on the shape and size of molecular imprinted polymer (MIP) beads prepared by precipitation polymerization has been evaluated using a chemometric approach. Molecularly imprinted microspheres for the selective recognition of fluoroquinolone antimicrobials were prepared in a one-step precipitation polymerization procedure using enrofloxacin (ENR) as the template molecule, methacrylic acid as functional monomer, 2-hydroxyethyl methacrylate as hydrophilic comonomer, and acetonitrile as the porogen. The type and amount of cross-linker, namely ethylene glycol dimethacrylate, divinylbenzene or trimethylolpropane trimethacrylate, to obtain monodispersed MIP spherical beads in the micrometer range was optimized using a simplex lattice design. Particle size and morphology were assessed by scanning electron microscopy, dynamic light scattering, and nitrogen adsorption measurements. Electron paramagnetic resonance spectroscopy in conjunction with a nitroxide as spin probe revealed information about the microviscosity and polarity of the binding sites in imprinted and nonimprinted polymer beads.

  8. STUDY OF ANTIMICROBIAL ACTION OF ESSENTIAL OIL FROM STEMS OF ROSMARINUS OFFICINALIS L. (LAMIACEAE

    Directory of Open Access Journals (Sweden)

    Z. M. Tohsirova

    2016-01-01

    Full Text Available The aim of this work was to investigate the antibacterial activities using the method of wells of Rosmarinus officinalis essential oil, introduced in the Botanical garden of PMPI. It is established that the essential oil has the most pronounced antibacterial activities against Staphylococcus aureus and Enterococcus faecalis, less – Escherichia coli and Candida albicans. Antimicrobial effect on the test-cultures of microorganisms Pseudamonas aeruginosa and Proteus vulgaris are not expressed.

  9. Antimicrobial Properties of Plant Essential Oils against Human Pathogens and Their Mode of Action: An Updated Review

    Directory of Open Access Journals (Sweden)

    Mallappa Kumara Swamy

    2016-01-01

    Full Text Available A wide range of medicinal and aromatic plants (MAPs have been explored for their essential oils in the past few decades. Essential oils are complex volatile compounds, synthesized naturally in different plant parts during the process of secondary metabolism. Essential oils have great potential in the field of biomedicine as they effectively destroy several bacterial, fungal, and viral pathogens. The presence of different types of aldehydes, phenolics, terpenes, and other antimicrobial compounds means that the essential oils are effective against a diverse range of pathogens. The reactivity of essential oil depends upon the nature, composition, and orientation of its functional groups. The aim of this article is to review the antimicrobial potential of essential oils secreted from MAPs and their possible mechanisms of action against human pathogens. This comprehensive review will benefit researchers who wish to explore the potential of essential oils in the development of novel broad-spectrum key molecules against a broad range of drug-resistant pathogenic microbes.

  10. Antimicrobial Properties of Plant Essential Oils against Human Pathogens and Their Mode of Action: An Updated Review

    Science.gov (United States)

    2016-01-01

    A wide range of medicinal and aromatic plants (MAPs) have been explored for their essential oils in the past few decades. Essential oils are complex volatile compounds, synthesized naturally in different plant parts during the process of secondary metabolism. Essential oils have great potential in the field of biomedicine as they effectively destroy several bacterial, fungal, and viral pathogens. The presence of different types of aldehydes, phenolics, terpenes, and other antimicrobial compounds means that the essential oils are effective against a diverse range of pathogens. The reactivity of essential oil depends upon the nature, composition, and orientation of its functional groups. The aim of this article is to review the antimicrobial potential of essential oils secreted from MAPs and their possible mechanisms of action against human pathogens. This comprehensive review will benefit researchers who wish to explore the potential of essential oils in the development of novel broad-spectrum key molecules against a broad range of drug-resistant pathogenic microbes. PMID:28090211

  11. Evaluation of antimicrobial activity of selected plant extracts by rapid XTT colorimetry and bacterial enumeration.

    Science.gov (United States)

    Al-Bakri, Amal G; Afifi, Fatma U

    2007-01-01

    The aim of this study was to screen and evaluate the antimicrobial activity of indigenous Jordanian plant extracts, dissolved in dimethylsulfoxide, using the rapid XTT assay and viable count methods. XTT rapid assay was used for the initial screening of antimicrobial activity for the plant extracts. Antimicrobial activity of potentially active plant extracts was further assessed using the "viable plate count" method. Four degrees of antimicrobial activity (high, moderate, weak and inactive) against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, respectively, were recorded. The plant extracts of Hypericum triquetrifolium, Ballota undulata, Ruta chalepensis, Ononis natrix, Paronychia argentea and Marrubium vulgare had shown promising antimicrobial activity. This study showed that while both XTT and viable count methods are comparable when estimating the overall antimicrobial activity of experimental substances, there is no strong linear correlation between the two methods.

  12. Biosynthesis, characterization and antimicrobial action of silver nanoparticles from root bark extract of Berberislycium Royle.

    Science.gov (United States)

    Mehmood, Ansar; Murtaza, Ghulam; Bhatti, Tariq Mahmood; Kausar, Rehana; Ahmed, Muhammad Jamil

    2016-01-01

    Various biological methods are being recognized for the fabrication of silver nanoparticles, which are used in several fields. The phytosynthesis of nanoparticles came out as a cost effective and enviro-friendly approach. When root bark extract of Berberis lycium was treated with silver ions, they reduced to silver nanoparticles, which were spherical, crystalline, size ranged from 10-100nm and capped by biomolecules. Synthesized silver nanoparticles were characterized by UV-visible spectroscopy, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD) and Fourier Transform Infra Red Spectroscopy (FTIR). The plant mediated synthesized silver nanoparticles showed pronounced antimicrobial activities against both Gram negative bacteria (Escherichia coli, Klebseilla pneumoniae, Pseudomonas aeruginosa) and Gram positive bacteria (Staphylococcus aureus and Bacillus subtilis). The plant mediated process proved to be non-toxic and low cost contender as reducing agent for synthesizing stable silver nanoparticles.

  13. Effects of gamma irradiation of the 60 Co on antimicrobial action of plant extracts of bark and leaves of Schinus terebinthifolius Raddi

    International Nuclear Information System (INIS)

    Silva, Edvane Borges da; Santos, Gustavo Henrique Farias dos; Amaral, Ademir de Jesus; Xisto, Kesia; Araujo, Rosilma de Oliveira

    2014-01-01

    This study aimed to evaluate the potential for antimicrobial activity in vitro of extracts of bark and leaves of S. terebinthifolius treated with 60 Co gamma radiation. 5,0 doses were used; 7.5 and 10 kGy, being held non-irradiated controls. To determine the antimicrobial activity was applied to the disc diffusion technique to evaluate the diameter of the inhibition zones against Gram-positive bacteria, gram-negative bacteria, alcohol-acid-resistant and yeast. Antimicrobial activity was considered significant for halos ≥ 15 mm. The results indicate an intensification of antimicrobial action of bark extracts, the 5.0 kGy, against S. aureus. Was held the micro dilution in broth to determine the minimum inhibitory concentration (MIC) and Minimum Bactericidal Concentration (MBC) of peels extracts, compared to eight clinical isolates of S. aureus. The MBC values showed that ionizing radiation did not produce the increased of anti bacteriostatic action of S. terebinthifolius, but the results indicated that S. terebinthifolius bark extracts can be used as an antimicrobial agent and ionizing radiation as an important alternative in this conservation feature

  14. Characterization of the branched antimicrobial peptide M6 by analyzing its mechanism of action and in vivo toxicity.

    Science.gov (United States)

    Pini, Alessandro; Giuliani, Andrea; Falciani, Chiara; Fabbrini, Monica; Pileri, Silvia; Lelli, Barbara; Bracci, Luisa

    2007-06-01

    We analyzed functional activity of the antimicrobial peptide M6 in vitro and in vivo. The peptide was identified by our group by phage library selection, rational modification and synthesis in a tetrabranched form (Pini et al., Antimicrob. Agents Chemother. 2005; 49: 2665-72). We found that it binds lipopolysaccharide, causes perforation of cell membranes without destroying external cell morphology and strongly binds DNA. The latter feature suggests that it could inhibit metabolic pathways, blocking DNA replication and/or transcription. We also observed that M6 does not stimulate humoral immune response when repeatedly administered to animals. We also analyzed M6 toxicity when administered to animals by intraperitoneal or by intravenous injection, determining a preliminary LD50 (125 and 37.5 mg/kg, respectively), which suggested that M6 could be used in vivo. These features make the antimicrobial branched peptide M6 a promising candidate for the development of a new antibacterial drug. Copyright (c) 2007 European Peptide Society and John Wiley & Sons, Ltd.

  15. Effect of different oral oxytetracycline treatment regimes on selection of antimicrobial resistant coliforms in nursery pigs.

    Science.gov (United States)

    Herrero-Fresno, Ana; Zachariasen, Camilla; Nørholm, Nanna; Holm, Anders; Christiansen, Lasse Engbo; Olsen, John Elmerdahl

    2017-09-01

    A major concern derived from using antimicrobials in pig production is the development of resistance. This study aimed to assess the impact of selected combinations of oral dose and duration of treatment with oxytetracycline (OTC) on selection of tetracycline resistant (TET-R) coliforms recovered from swine feces. The work encompassed two studies: 1) OTC 5mg/kg and 20mg/kg were administered to nursery pigs for 3 and 10days, respectively, under controlled experimental conditions, and 2) 10mg/kg, 20mg/kg and 30mg/kg OTC were given to a higher number of pigs for 6, 3 and 2days, respectively, under field conditions. Statistical modeling was applied to analyze trends in the proportion of TET-R coliforms. In the experimental study, no statistical difference in proportion of TET-R coliforms was observed between treatments at the end of the trial (day 18) and compared to day 0. In the field study, treatment had a significant effect on the proportion of TET-R bacteria two days after the end of treatment (2dAT) with the regimes "low dose-six days" and "medium dose-three days" yielding the highest and lowest proportions of TET-R strains, respectively. No indication of co-selection for ampicillin- and sulphonamide -R bacteria was observed for any treatment at 2dAT. By the end of the nursery period, the proportion of TET-R bacteria was not significantly different between treatments and compared to day 0. Our results suggest that similar resistance levels might be obtained by using different treatment regimes regardless of the combinations of oral dose-duration of treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Macromolecule biosynthesis assay and fluorescence spectroscopy methods to explore antimicrobial peptide mode(s) of action

    DEFF Research Database (Denmark)

    Jana, Bimal; Baker, Kristin Renee; Guardabassi, Luca

    2017-01-01

    the biosynthesis rate of macromolecules (e.g., DNA, RNA, protein, and cell wall) and the cytoplasmic membrane proton motive force (PMF) energy can help to unravel the diverse modes of action of AMPs. Here, we present an overview of macromolecule biosynthesis rate measurement and fluorescence spectroscopy methods...

  17. Effect of selective decontamination on antimicrobial resistance in intensive care units: a systematic review and meta-analysis.

    Science.gov (United States)

    Daneman, Nick; Sarwar, Syed; Fowler, Robert A; Cuthbertson, Brian H

    2013-04-01

    Many meta-analyses have shown reductions in infection rates and mortality associated with the use of selective digestive decontamination (SDD) or selective oropharyngeal decontamination (SOD) in intensive care units (ICUs). These interventions have not been widely implemented because of concerns that their use could lead to the development of antimicrobial resistance in pathogens. We aimed to assess the effect of SDD and SOD on antimicrobial resistance rates in patients in ICUs. We did a systematic review of the effect of SDD and SOD on the rates of colonisation or infection with antimicrobial-resistant pathogens in patients who were critically ill. We searched for studies using Medline, Embase, and Cochrane databases, with no limits by language, date of publication, study design, or study quality. We included all studies of selective decontamination that involved prophylactic application of topical non-absorbable antimicrobials to the stomach or oropharynx of patients in ICUs, with or without additional systemic antimicrobials. We excluded studies of interventions that used only antiseptic or biocide agents such as chlorhexidine, unless antimicrobials were also included in the regimen. We used the Mantel-Haenszel model with random effects to calculate pooled odds ratios. We analysed 64 unique studies of SDD and SOD in ICUs, of which 47 were randomised controlled trials and 35 included data for the detection of antimicrobial resistance. When comparing data for patients in intervention groups (those who received SDD or SOD) versus data for those in control groups (who received no intervention), we identified no difference in the prevalence of colonisation or infection with Gram-positive antimicrobial-resistant pathogens of interest, including meticillin-resistant Staphylococcus aureus (odds ratio 1·46, 95% CI 0·90-2·37) and vancomycin-resistant enterococci (0·63, 0·39-1·02). Among Gram-negative bacilli, we detected no difference in aminoglycoside-resistance (0

  18. Effect of different scenarios for selective dry-cow therapy on udder health, antimicrobial usage, and economics.

    Science.gov (United States)

    Scherpenzeel, C G M; den Uijl, I E M; van Schaik, G; Riekerink, R G M Olde; Hogeveen, H; Lam, T J G M

    2016-05-01

    The goal of dry-cow therapy (DCT) is to reduce the prevalence of intramammary infections (IMI) by eliminating existing IMI at drying off and preventing new IMI from occurring during the dry period. Due to public health concerns, however, preventive use of antimicrobials has become questionable. In this study, we evaluated the effects of 8 scenarios for selecting animals for DCT, taking into account variation in parity and cow-level somatic cell count (SCC) at drying off. The aim of this study was to evaluate udder health, antimicrobial usage, and economics at the herd level when using different scenarios for selecting cows for DCT. To enable calculation and comparison of the effects of different scenarios to select cows for DCT in an "average" herd, we created an example herd, with a virtual herd size of 100 dairy cows to be calving during a year. Udder health, antimicrobial usage, and economics were evaluated during the dry period and the first 100 d in lactation, the period during which the greatest effect of DCT is expected. This leads to an estimated 13,551 cow-days at risk during a year in a 100-cow dairy herd. In addition to a blanket DCT (BDCT) scenario, we developed 7 scenarios to select cows for DCT based on SCC. The scenarios covered a range of possible approaches to select low-SCC cows for DCT, all based on cow-level SCC thresholds on the last milk recording before drying off. The incidence rate of clinical mastitis in the example herd varied from 11.6 to 14.5 cases of clinical mastitis per 10,000 cow-days at risk in the different scenarios, and the prevalence of subclinical mastitis varied from 38.8% in scenario 1 (BDCT) to 48.3% in scenario 8. Total antimicrobial usage for DCT and clinical mastitis treatment varied over the scenarios from 1.27 (scenario 8) to 3.15 animal daily dosages (BDCT), leading to a maximum reduction in antimicrobial usage of 60% for scenario 8 compared with BDCT. The total costs for each of the scenarios showed little variation

  19. Examination of antimicrobial activity of selected non-antibiotic medicinal preparations.

    Science.gov (United States)

    Kruszewska, Hanna; Zareba, Tomasz; Tyski, Stefan

    2012-01-01

    The aim of this study was to detect and characterize the antimicrobial activity of non-antibiotic drugs, selected from the pharmaceutical products analyzed during the state control performed in National Medicines Institute, Warszawa, Poland. In 2010, over 90 pharmaceutical preparations have been randomly chosen from different groups of drugs. The surveillance study was performed on standard ATCC microbial strains used for drug control: S. aureus, E. coli, P. aeruginosa and C. albicans. It was shown that the drugs listed below inhibited growth of at least one of the examined strains: Arketis 20 mg tab. (paroxetine), Buvasodil 150 mg tab. (buflomedile), Halidor 100 mg tab. (bencyclane), Hydroxyzinum espefa 25 mg tab. (hydroxyzine), Norifaz 35 mg tab. (risedronate), Strattera 60 mg cap. (atomoxetine), Tamiflu 75 mg tab. (oseltamivir), Valpro-ratiopharm Chrono 300 mg tab. with longer dissolution (valproate), Vetminth oral paste 24 g+3 g/100 mL (niclozamide, oxybendazol). Strattera cap. showed broad activity spectrum. It inhibited growth of all examined strains (MIC of active substance -- atomoxetine ranged between 2.6-13 mg/mL).

  20. Short, multiple-stranded β-hairpin peptides have antimicrobial potency with high selectivity and salt resistance.

    Science.gov (United States)

    Chou, Shuli; Shao, Changxuan; Wang, Jiajun; Shan, Anshan; Xu, Lin; Dong, Na; Li, Zhongyu

    2016-01-01

    The β-hairpin structure has been proposed to exhibit potent antimicrobial properties with low cytotoxicity, thus, multiple β-hairpin structures have been proved to be highly stable in structures containing tightly packed hydrophobic cores. The aim of this study was to develop peptide-based synthetic strategies for generating short, but effective AMPs as inexpensive antimicrobial agents. Multiple-stranded β-hairpin peptides with the same β-hairpin unit, (WRXxRW)n where n=1, 2, 3, or 4 and Xx represent the turn sequence, were synthesized, and their potential as antimicrobial agents was evaluated. Owning to the tightly packed hydrophobic core and paired Trp of this multiple-stranded β-hairpin structure, all the 12-residues peptides exhibited high cell selectivity towards bacterial cells over human red blood cells (hRBCs), and the peptide W2 exhibited stronger antimicrobial activities with the MIC values of 2-8μM against various tested bacteria. Not only that, but W2 also showed obvious synergy with streptomycin and chloramphenicol against Escherichia coli, and displayed synergy with ciprofloxacin against Staphylococcus aureus with the FICI values ⩽0.5. Fluorescence spectroscopy and electron microscopy analyses indicated that W2 kills microbial cells by permeabilizing the cell membrane and damaging membrane integrity. Collectively, based on the multiple β-hairpin peptides, the ability to develop libraries of short and effective peptides will be a powerful approach to the discovery of novel antimicrobial agents. We successfully screened a peptide W2 ((WRPGRW)2) from a series of multiple-stranded β-hairpin antimicrobial peptides based on the "S-shaped" motif that induced the formation of a globular structure, and Trp zipper was used to replace the disulfide bonds to reduce the cost of production. This novel structure applied to AMPs improved cell selectivity and salt stability. The findings of this study will promote the development of peptide

  1. The rhizospheres of traditional medicinal plants in Panxi, China, host a diverse selection of actinobacteria with antimicrobial properties.

    Science.gov (United States)

    Zhao, Ke; Penttinen, Petri; Chen, Qiang; Guan, Tongwei; Lindström, Kristina; Ao, Xiaoling; Zhang, Lili; Zhang, Xiaoping

    2012-06-01

    Actinobacteria are a prolific source of antibiotics. Since the rate of discovery of novel antibiotics is decreasing, actinobacteria from unique environments need to be explored. In particular, actinobacterial biocontrol strains from medicinal plants need to be studied as they can be a source of potent antibiotics. We combined culture-dependent and culture-independent methods in analyzing the actinobacterial diversity in the rhizosphere of seven traditional medicinal plant species from Panxi, China, and assessed the antimicrobial activity of the isolates. Each of the plant species hosted a unique set of actinobacterial strains. Out of the 64 morphologically distinct isolates, half were Streptomyces sp., eight were Micromonospora sp., and the rest were members of 18 actinobacterial genera. In particular, Ainsliaea henryi Diels. hosted a diverse selection of actinobacteria, although the 16S ribosomal RNA (rRNA) sequence identity ranges of the isolates and of the 16S rRNA gene clone library were not congruent. In the clone library, 40% of the sequences were related to uncultured actinobacteria, emphasizing the need to develop isolation methods to assess the full potential of the actinobacteria. All Streptomyces isolates showed antimicrobial activity. While the antimicrobial activities of the rare actinobacteria were limited, the growth of Escherichia coli, Verticillium dahliae, and Fusarium oxysporum were inhibited only by rare actinobacteria, and strains related to Saccharopolyspora shandongensis and Streptosporangium roseum showed broad antimicrobial activity.

  2. Phenolic profile and antimicrobial activities to selected microorganisms of some wild medical plant from Slovakia

    Directory of Open Access Journals (Sweden)

    Lukáš Hleba

    2014-08-01

    Full Text Available Objective: To investigate the chemical composition and antimicrobial activity of the methanol extracts of Tussilago farfara (T. farfara, Equisetum arvense, Sambucus nigra (S. nigra and Aesculus hippocastanum. Methods: The antimicrobial activities of the extracts against Enterococcus raffinosus, Escherichia coli, Lactobacillus rhamnosus, Pseudomonas aeruginosa, Serratia rubidaea, Saccharomyces cerevisiae and Staphylococcus epidermis were determined by the microbroth dilution method according to Clinical and Laboratory Standards Institute, while the concentrations of main phenolic acids and flavonoids in the form of trimethylsilyl ethers were analysed using gas chromatography-mass spectrometry. The probit analysis was used for statistical evaluation. Results: Of the 4 plant tested, all extracts showed a significant antimicrobial activity against one or more species of examined microorganisms. The most active antimicrobial plant extract was gathered from T. farfara, followed by Aesculus hippocastanum and Equisetum arvense. The extract from S. nigra showed no antimicrobial effects. The flavonoids quercetin and kaempferol, as well as several phenolic acids (p-hydroxybenzoic acid, gallic acid, ferulic acid and caffeic acid were identified in all extracts. The highest concentrations of bioactive compounds were detected in the extracts of T. farfara (9 587.6 µg/mg quercetin and 4 875.3 µg/mg caffeic acid as well as S. nigra (4788.8 µg/mg kaempferol. Conclusions: We can state that the methanolic plant extract of T. farfara showed the strongest antimicrobial activity against Saccharomyces cerevisiae as well as other tested microorganisms. At the same time, a good antimicrobial activity was found in the other medical plant extracts as well. No antimicrobial effect of the S. nigra extract was found with respect to the growth of Pseudomonas aeruginosa, Enterococcus raffinosus and Saccharomyces cerevisiae.

  3. Tetracycline compounds with non-antimicrobial organ protective properties: possible mechanisms of action

    Science.gov (United States)

    Griffin, Michael O.; Ceballos, Guillermo; Villarreal, Francisco

    2010-01-01

    Tetracyclines were developed as a result of the screening of soil samples for antibiotics. The firstt of these compounds, chlortetracycline, was introduced in 1947. Tetracyclines were found to be highly effective against various pathogens including rickettsiae, as well as both gram-positive and gram-negative bacteria, thus becoming the first class of broad spectrum antibiotics. Many other interesting properties, unrelated to their antibiotic activity, have been identified for tetracyclines which have led to widely divergent experimental and clinical uses. For example, tetracyclines are also an effective anti-malarial drug. Minocycline, which can readily cross cell membranes, is known to be a potent anti-apoptotic agent. Another tetracycline, doxycycline is known to exert anti-protease activities. Doxycycline can inhibit matrix metalloproteinases which contribute to tissue destruction activities in diseases such as periodontitis. A large body of literature has provided additional evidence for the “beneficial” actions of tetracyclines, including their ability to act as reactive oxygen species scavengers and anti-inflammatory agents. This review provides a summary of tetracycline’s multiple mechanisms of action as a means to understand their beneficial effects. PMID:20951211

  4. Selective effects of an octopus toxin on action potentials

    Science.gov (United States)

    Dulhunty, Angela; Gage, Peter W.

    1971-01-01

    1. A lethal, water soluble toxin (Maculotoxin, MTX) with a molecular weight less than 540, can be extracted from the salivary glands of an octopus (Hapalochlaena maculosa). 2. MTX blocks action potentials in sartorius muscle fibres of toads without affecting the membrane potential. Delayed rectification is not inhibited by the toxin. 3. At low concentrations (10-6-10-5 g/ml.) MTX blocks action potentials only after a certain number have been elicited. The number of action potentials, which can be defined accurately, depends on the concentration of MTX and the concentration of sodium ions in the extracellular solution. 4. The toxin has no post-synaptic effect at the neuromuscular junction and it is concluded that it blocks neuromuscular transmission by inhibiting action potentials in motor nerve terminals. PMID:4330930

  5. Characterizing the structure-function relationship reveals the mode of action of a novel antimicrobial peptide, P1, from jumper ant Myrmecia pilosula.

    Science.gov (United States)

    Tseng, Tien-Sheng; Tsai, Keng-Chang; Chen, Chinpan

    2017-06-01

    Microbial infections of antibiotic-resistant strains cause serious diseases and have a significant impact on public health worldwide, so novel antimicrobial drugs are urgently needed. Insect venoms, a rich source of bioactive components containing antimicrobial peptides (AMPs), are attractive candidates for new therapeutic agents against microbes. Recently, a novel peptide, P1, identified from the venom of the Australian jumper ant Myrmecia pilosula, showed potent antimicrobial activities against both Gram-negative and Gram-positive bacteria, but its structure-function relationship is unknown. Here, we used biochemical and biophysical techniques coupled with computational simulations to explore the mode of action of P1 interaction with dodecylphosphocholine (DPC) micelles as a model membrane system. Our circular dichroism (CD) and NMR studies revealed an amphipathic α-helical structure for P1 upon interaction with DPC micelles. A paramagnetic relaxation enhancement approach revealed that P1 orients its α-helix segment (F6-G14) into DPC micelles. In addition, the α-helix segment could be essential for membrane permeabilization and antimicrobial activity. Moreover, the arginine residues R8, R11, and R15 significantly contribute to helix formation and membrane-binding affinity. The lysine residue K19 of the C-terminus functionally guides P1 to interact with DPC micelles in the early interaction stage. Our study provides insights into the mode of action of P1, which is valuable in modifying and developing potent AMPs as antibiotic drugs.

  6. Antimicrobial Drugs in Fighting against Antimicrobial Resistance

    OpenAIRE

    Cheng, Guyue; Dai, Menghong; Ahmed, Saeed; Hao, Haihong; Wang, Xu; Yuan, Zonghui

    2016-01-01

    The outbreak of antimicrobial resistance, together with the lack of newly developed antimicrobial drugs, represents an alarming signal for both human and animal healthcare worldwide. Selection of rational dosage regimens for traditional antimicrobial drugs based on pharmacokinetic/pharmacodynamic principles as well as development of novel antimicrobials targeting new bacterial targets or resistance mechanisms are key approaches in tackling AMR. In addition to the cellular level resistance (i....

  7. Evaluation of Phenolic Content Variability along with Antioxidant, Antimicrobial, and Cytotoxic Potential of Selected Traditional Medicinal Plants from India.

    Science.gov (United States)

    Singh, Garima; Passsari, Ajit K; Leo, Vincent V; Mishra, Vineet K; Subbarayan, Sarathbabu; Singh, Bhim P; Kumar, Brijesh; Kumar, Sunil; Gupta, Vijai K; Lalhlenmawia, Hauzel; Nachimuthu, Senthil K

    2016-01-01

    Plants have been used since ancient times as an important source of biologically active substances. The aim of the present study was to investigate the phytochemical constituents (flavonoids and phenolics), antioxidant potential, cytotoxicity against HepG2 (human hepato carcinoma) cancer cell lines, and the antimicrobial activity of the methanol extract of selected traditional medicinal plants collected from Mizoram, India. A number of phenolic compounds were detected using HPLC-DAD-ESI-TOF-MS, mainly Luteolin, Kaempferol, Myricetin, Gallic Acid, Quercetin and Rutin, some of which have been described for the first time in the selected plants. The total phenolic and flavonoid contents showed high variation ranging from 4.44 to 181.91 μg of Gallic Acid equivalent per milligram DW (GAE/mg DW) and 3.17 to 102.2 μg of Quercetin/mg, respectively. The antioxidant capacity was determined by DPPH (IC50 values ranges from 34.22 to 131.4 μg/mL), ABTS (IC50 values ranges from 24.08 to 513.4 μg/mL), and reducing power assays. Antimicrobial activity was assayed against gram positive (Staphylococcus aureus), gram negative (Escherichia coli, Pseudomonas aeruginosa), and yeast (Candida albicans) demonstrating that the methanol extracts of some plants were efficacious antimicrobial agents. Additionally, cytotoxicity was assessed on human hepato carcinoma (HepG2) cancer cell lines and found that the extracts of Albizia lebbeck, Dillenia indica, and Bombax ceiba significantly decreased the cell viability at low concentrations with IC50 values of 24.03, 25.09, and 29.66 μg/mL, respectively. This is the first report of detection of phenolic compounds along with antimicrobial, antioxidant and cytotoxic potential of selected medicinal plants from India, which indicates that these plants might be valuable source for human and animal health.

  8. Evaluation of phenolic content variability, antioxidant, antimicrobial and cytotoxic potential of selected traditional medicinal plants from India

    Directory of Open Access Journals (Sweden)

    Garima eSingh

    2016-03-01

    Full Text Available Plants have been used since ancient times as an important source of biologically active substances. The aim of the present study was to investigate the phytochemical constituents (flavonoids and phenolics, antioxidant potential, cytotoxicity against HepG2 (human hepato carcinoma cancer cell lines and the antimicrobial activity of the methanol extract of selected traditional medicinal plants collected from Mizoram, India. A number of phenolic compounds were detected using HPLC-DAD-ESI-TOF-MS, mainly Luteolin, Kaempferol, Myricetin, Gallic Acid, Quercetin and Rutin, some of which have been described for the first time in the selected plants. The total phenolic and flavonoid contents showed high variation ranging from 4.44 to 181.91 µg of Gallic Acid equivalent per milligram DW (GAE/mg DW and 3.17 to 102.2 µg of Quercetin/mg, respectively. The antioxidant capacity was determined by DPPH (IC50 values ranges from 34.22 to 131.4 µg/mL, ABTS (IC50 values ranges from 24.08 to 513.4 µg/mL and reducing power assays. Antimicrobial activity was assayed against gram positive (Staphylococcus aureus, gram negative (Escherichia coli, Pseudomonas aeruginosa and yeast (Candida albicans demonstrating that the methanol extracts of some plants were efficacious antimicrobial agents. Additionally, cytotoxicity was assessed on human hepato carcinoma (HepG2 cancer cell lines and found that the extracts of Albizia lebbeck, Dillenia indica and Bombax ceiba significantly decreased the cell viability at low concentrations with IC50 values of 24.03, 25.09 and 29.66 µg/mL, respectively. This is the first report of detection of phenolic compounds along with antimicrobial, antioxidant and cytotoxic potential of selected medicinal plants from India, which indicates that these plants might be valuable source for human and animal health.

  9. Nuclear facility decommissioning and site remedial actions: a selected bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Owen, P.T.; Knox, N.P.; Fielden, J.M.; Johnson, C.A.

    1982-09-01

    This bibliography contains 693 references with abstracts on the subject of nuclear facility decommissioning, uranium mill tailings management, and site remedial actions. Foreign, as well as domestic, literature of all types - technical reports, progress reports, journal articles, conference papers, symposium proceedings, theses, books, patents, legislation, and research project descriptions - has been included in this publication. The bibliography contains scientific (basic research as well as applied technology), economic, regulatory, and legal literature pertinent to the US Department of Energy's Remedial Action Program. Major chapters are Surplus Facilities Management Program, Nuclear Facilities Decommissioning, Formerly Utilized Sites Remedial Action Program, Uranium Mill Tailings Remedial Action Program, Grand Junction Remedial Action Program, and Uranium Mill Tailings Management. Chapter sections for chapters 1 and 2 include: Design, Planning, and Regulations; Site Surveys; Decontamination Studies; Dismantlement and Demolition; Land Decontamination and Reclamation; Waste Disposal; and General Studies. The references within each chapter are arranged alphabetically by leading author. References having no individual author are arranged by corporate author or by title. Indexes are provided for (1) author; (2) corporate affiliation; (3) title; (4) publication description; (5) geographic location; and (6) keywords. An appendix of 202 bibliographic references without abstracts or indexes has been included in this bibliography. This appendix represents literature identified but not abstracted due to time constraints.

  10. Nuclear facility decommissioning and site remedial actions: a selected bibliography

    International Nuclear Information System (INIS)

    Owen, P.T.; Knox, N.P.; Fielden, J.M.; Johnson, C.A.

    1982-09-01

    This bibliography contains 693 references with abstracts on the subject of nuclear facility decommissioning, uranium mill tailings management, and site remedial actions. Foreign, as well as domestic, literature of all types - technical reports, progress reports, journal articles, conference papers, symposium proceedings, theses, books, patents, legislation, and research project descriptions - has been included in this publication. The bibliography contains scientific (basic research as well as applied technology), economic, regulatory, and legal literature pertinent to the US Department of Energy's Remedial Action Program. Major chapters are Surplus Facilities Management Program, Nuclear Facilities Decommissioning, Formerly Utilized Sites Remedial Action Program, Uranium Mill Tailings Remedial Action Program, Grand Junction Remedial Action Program, and Uranium Mill Tailings Management. Chapter sections for chapters 1 and 2 include: Design, Planning, and Regulations; Site Surveys; Decontamination Studies; Dismantlement and Demolition; Land Decontamination and Reclamation; Waste Disposal; and General Studies. The references within each chapter are arranged alphabetically by leading author. References having no individual author are arranged by corporate author or by title. Indexes are provided for (1) author; (2) corporate affiliation; (3) title; (4) publication description; (5) geographic location; and (6) keywords. An appendix of 202 bibliographic references without abstracts or indexes has been included in this bibliography. This appendix represents literature identified but not abstracted due to time constraints

  11. [Selection of indicators for continuous monitoring of the impact of programs optimizing antimicrobial use in Primary Care].

    Science.gov (United States)

    Fernández-Urrusuno, Rocío; Flores-Dorado, Macarena; Moreno-Campoy, Eva; Montero-Balosa, M Carmen

    2015-05-01

    To determine core indicators for monitoring quality prescribing in Primary Care based on the evidence, and to assess the feasibility of these indicators for monitoring the use of antibiotics. A literature review was carried out on quality indicators for antimicrobial prescribing through an electronic search limited to the period 2001-2012. It was completed with an "ad hoc" search on the websites of public national and international health services. Finally, indicators were chosen by consensus by a multidisciplinary group of professionals dedicated to managing infections from several areas. The feasibility and applicability of these indicators was verified through the reporting and use of data in the prescription database. Twenty two indicators were found. The consensus group selected 16 indicators. Eleven of them measure the specific antimicrobial selection, and 5 are consumption rates. The indicators were successfully applied to the prescription database, being able to make comparisons between different geographical areas and to observe trends in prescriptions. The definition of a basic set of indicators to monitor antibiotic use adapted to local conditions is required. The results of these indicators can be used for feedback to professionals and for evaluating the impact of programs aimed at improving antimicrobial use. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  12. WATER SORPTION PROPERTIES AND ANTIMICROBIAL ACTION OF ZINC OXIDE NANO PARTICLES LOADED SAGO STARCH FILM

    Directory of Open Access Journals (Sweden)

    Sunil Bajpai

    2013-02-01

    Full Text Available In this work, sago starch based films have been loaded with ZnO nanoparticles prepared insitu via using an unique equilibration-cum-hydrothermal approach. The films have been characterized by XRD, DSC,SPR ,FTIR and SEM analysis. The moisture absorption behavior of plain and ZnO nanoparticles loaded films have been studied at 23, 31 and 37o C.The equilibrium moisture uptake data was found to fit well on GAB isotherm model and the monolayer sorption capacity Mo for the plain and ZnO nanoparticles loaded films was 0.089, 0.039 ,0.021 g/g and 0.042, 0.012, 0.007 g/g at 23,31 and 37 oC respectively. Moreover, the water vapor transmission rates (WVTR for plain and ZnO nanoparticles loaded films at 23,31,37 oC were 11.19x10-4, 48.9x10-4, 62.1x10-4 and 3.73 x10-4, 6.21x10-4, 24.8x10-4 respectively. These films have shown excellent antibacterial action against model bacteria E.coli when investigated qualitatively by zone inhibition method. Films exhibit great potential to be used as packaging films to protect food stuff against microbial contaminents.

  13. New perspective of dendrobium crumenatum orchid for antimicrobial activity against selected pathogenic bacteria

    International Nuclear Information System (INIS)

    Sandrasagaran, U.M.; Murugaiyah, V.

    2014-01-01

    The present study was undertaken to investigate the potential anti-microbial activity from different parts of Dendrobium crumenatum (leaf, stem, root and pseudo-bulb) against 8 pathogenic bacteria. The antimicrobial activities were determined by using disc diffusion assay, microdilution test for determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The methanolic extracts of stem, root and pseudo-bulb displayed antimicrobial activity comparable to that of the standard antibiotics. Stem extract of D. crumenatum had the most potent antimicrobial activity against Staphylococcus aureus, Klebsiella pneumoniae and Enterobacter aerogenes with MIC values of 0.39, 0.195 and 0.195 mg/mL, respectively. Root and stem extracts were found to be active against Streptococcus pneumoniae, Shigella dysentriae and Saccharomyces cerevisiae with MIC values of 0.78 mg/ml compared to 0.00312 mg/mL, 0.025 mg/mL and 0.0125 mg/mL of standard antibiotics of amoxcillin, chloramphenicol and kanamycin. Stem and root extracts yield MBC values in the range of 0.78 mg/mL to 6.25 mg/mL against Staphylococcus aureus, Enterobacter aerogenes, Klebsiella pneumoniae and Saccharomyces cerevisiae. The present study showed that D. crumenatum exhibited potential antimicrobial activity which could be due to the presence of alkaloid and flavonoid compounds and this is a first report on South East Asia region's wild orchid. (author)

  14. Exploring Heuristic Action Selection in Agent Programming (extended abstract)

    NARCIS (Netherlands)

    Hindriks, K.V.; Jonker, C.M.; Pasman, W.

    2008-01-01

    Rational agents programmed in agent programming languages derive their choice of action from their beliefs and goals. One of the main benefits of such programming languages is that they facilitate a highlevel and conceptually elegant specification of agent behaviour. Qualitative concepts alone,

  15. The Use of Evolution in a Central Action Selection Model

    Directory of Open Access Journals (Sweden)

    F. Montes-Gonzalez

    2007-01-01

    Full Text Available The use of effective central selection provides flexibility in design by offering modularity and extensibility. In earlier papers we have focused on the development of a simple centralized selection mechanism. Our current goal is to integrate evolutionary methods in the design of non-sequential behaviours and the tuning of specific parameters of the selection model. The foraging behaviour of an animal robot (animat has been modelled in order to integrate the sensory information from the robot to perform selection that is nearly optimized by the use of genetic algorithms. In this paper we present how selection through optimization finally arranges the pattern of presented behaviours for the foraging task. Hence, the execution of specific parts in a behavioural pattern may be ruled out by the tuning of these parameters. Furthermore, the intensive use of colour segmentation from a colour camera for locating a cylinder sets a burden on the calculations carried out by the genetic algorithm.

  16. Response selection difficulty modulates the behavioral impact of rapidly learnt action effects.

    Directory of Open Access Journals (Sweden)

    Uta eWolfensteller

    2014-12-01

    Full Text Available It is well established that we can pick up action effect associations when acting in a free-choice intentional mode. However, it is less clear whether and when action effect associations are learnt and actually affect behavior if we are acting in a forced-choice mode, applying a specific stimulus-response (S-R rule. In the present study, we investigated whether response selection difficulty imposed by S-R rules influences the initial rapid learning and the behavioral expression of previously learnt but weakly practiced action effect associations when those are re-activated by effect exposure. Experiment 1 showed that the rapid acquisition of action effect associations is not directly influenced by response selection difficulty. By contrast, the behavioral expression of re-activated action effect associations is prevented when actions are directly activated by highly over-learnt response cues and thus response selection difficulty is low. However, all three experiments showed that if response selection difficulty is sufficiently high during re-activation, the same action effect associations do influence behavior. Experiment 2 and 3 revealed that the effect of response selection difficulty cannot be fully reduced to giving action effects more time to prime an action, but seems to reflect competition during response selection. Finally, the present data suggest that when multiple novel rules are rapidly learnt in succession, which requires a lot of flexibility, action effect associations continue to influence behavior only if response selection difficulty is sufficiently high. Thus, response selection difficulty might modulate the impact of experiencing multiple learning episodes on action effect expression and learning, possibly via inducing different strategies.

  17. Specialised cleaning associated with antimicrobial coatings for reduction of hospital acquired infection. Opinion of the COST Action Network AMiCI (CA15114).

    Science.gov (United States)

    Dunne, Suzanne S; Ahonen, Merja; Modic, Martina; Crijns, Francy Rl; Keinänen-Toivola, Minna M; Meinke, Ruth; Keevil, C William; Gray, Jim; O'Connell, Nuala H; Dunne, Colum P

    2018-03-14

    Recognized issues with poor hand hygiene compliance among healthcare workers, and reports of re-contamination of previously chemically disinfected surfaces through hand contact, emphasize need for novel hygiene methods in addition to those currently available. One such approach involves antimicrobial (nano)-coatings (AMC), whereby integrated active ingredients are responsible for elimination of microorganisms that come into contact with treated surfaces. While widely studied under laboratory conditions with promising results, studies under real life healthcare conditions are scarce. The views of 75 contributors from 30 European countries were collated regarding specialised cleaning associated with antimicrobial coatings for reduction of hospital acquired infection. There was unanimous agreement that generation of scientific guidelines for cleaning of antimicrobial coatings, using traditional or new processes, are needed. Specific topics included: understanding mechanisms of action of cleaning materials and their physical interactions with conventional and antimicrobial coatings; that assessments mimic the life-cycle of coatings to determine the impact of repetitive cleaning and other aspects of ageing (e.g., exposure to sunlight); determining concentrations of AMC-derived biocides in effluents, and development of effective de-activation and sterilisation treatments for cleaning effluents. Further, the consensus opinion was that prior to widespread implementation of AMCs, the varying responsibilities of involved clinical, healthcare management, cleaning services, and environmental safety stakeholders need clarification. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  18. Effect of calcium and magnesium on the antimicrobial action of enterocin LR/6 produced by Enterococcus faecium LR/6.

    Science.gov (United States)

    Kumar, Manoj; Srivastava, Sheela

    2011-06-01

    Enterococci are well-known producers of antimicrobial peptides (enterocins) that possess potential as biopreservatives in food. In this study, divalent cations and release of intracellular potassium were used to assess the mechanism of interaction and killing of enterocin LR/6 produced by Enterococcus faecium LR/6 on three target Gram-positive and Gram-negative bacteria, namely Micrococcus luteus, Enterococcus sp. strain LR/3 and Escherichia coli K-12. Whilst treatment with enterocin LR/6 in all cases led to a significant loss of viability, suggesting a bactericidal mode of action, E. coli K-12 showed better tolerance than the other two strains. Bacteriocins have generally been reported to create pores in the membrane of sensitive cells and this function is diminished by divalent cations. In this study it was shown that Ca(2+) and Mg(2+) markedly improved the viability of enterocin LR/6-treated cells in a concentration-dependent manner. K(+) release as a sign of membrane leakiness was higher in M. luteus compared with the other two test strains. In agreement with the viability response, pre-exposure to Ca(2+) and Mg(2+) substantially reduced the amount of K(+) leakage by M. luteus and Enterococcus sp.; in the case of E. coli K-12, no leakage of K(+) was recorded. These results suggest that enterocin LR/6, which possesses good antibacterial potential, may not be very effective as a preservative in foods containing high concentrations of calcium and magnesium. Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  19. Antimicrobial activity of some selected species of genus .I.Nigella./I..

    Czech Academy of Sciences Publication Activity Database

    Kokoška, L.; Rada, V.; Vaněk, Tomáš; Nepovím, Aleš

    2002-01-01

    Roč. 2, Supl. 1 (2002), s. 180 ISSN 1576-0952. [Annual Congress of the Society for Medicinal Plant Research /50./. 08.09.2002-12.09.2002, Barcelona] R&D Projects: GA MŠk OC 843.10 Institutional research plan: CEZ:AV0Z4055905 Keywords : antimicrobial activity Subject RIV: EI - Biotechnology ; Bionics

  20. Side Chain Hydrophobicity Modulates Therapeutic Activity and Membrane Selectivity of Antimicrobial Peptide Mastoparan-X

    DEFF Research Database (Denmark)

    Henriksen, Jonas Rosager; Etzerodt, Thomas Povl; Gjetting, Torben

    2014-01-01

    The discovery of new anti-infective compounds is stagnating and multi-resistant bacteria continue to emerge, threatening to end the "antibiotic era''. Antimicrobial peptides (AMPs) and lipo-peptides such as daptomycin offer themselves as a new potential class of antibiotics; however, further opti...

  1. Antimicrobial peptide exposure selects for Staphylococcus aureus resistance to human defence peptides

    DEFF Research Database (Denmark)

    Kubicek-Sutherland, Jessica Z.; Lofton, Hava; Vestergaard, Martin

    2017-01-01

    Background: The clinical development of antimicrobial peptides (AMPs) is currently under evaluation to combat the rapid increase in MDR bacterial pathogens. However, many AMPs closely resemble components of the human innate immune system and the ramifications of prolonged bacterial exposure to AM...

  2. Chemical analysis, antimicrobial and anti-oxidative properties of Daucus gracilis essential oil and its mechanism of action

    Directory of Open Access Journals (Sweden)

    Meriem El Kolli

    2016-01-01

    Conclusions: D. gracilis EO showed potent antimicrobial and anti-oxidative activities and had acted on the cytoplasm membrane. These activities could be exploited in the food industry for food preservation.

  3. Prokaryotic Selectivity, Anti-endotoxic Activity and Protease Stability of Diastereomeric and Enantiomeric Analogs of Human Antimicrobial Peptide LL-37

    International Nuclear Information System (INIS)

    Nan, Yong Hai; Lee, Bongju; Shin, Song Yub

    2012-01-01

    LL-37 is the only antimicrobial peptide (AMP) of the human cathelicidin family. In addition to potent antimicrobial activity, LL-37 is known to have the potential to inhibit lipolysaccharide (LPS)-induced endotoxic effects. To provide the stability to proteolytic digestion and increase prokaryotic selectivity and/or anti-endotoxic activity of two Lys/Trp-substituted 19-meric anti-microbial peptides (a4-W1 and a4-W2) designed from IG-19 (residues 13-31 of LL-37), we synthesized the diastereomeric peptides (a4-W1-D and a4-W2-D) with D-amino acid substitution at positions 3, 7, 10, 13 and 17 of a4-W1 and a4-W2, respectively and the enantiomeric peptides (a4-W1-E and a4-W2-E) composed D-amino acids. The diastereomeric peptides exhibited the best prokaryotic selectivity and effective protease stability, but no or less anti-endotoxic activity. In contrast, the enantiomeric peptides had not only prokaryotic selectivity and anti-endotoxic activity but also protease stability. Our results suggest that the hydrophobicity and α-helicity of the peptide is important for anti-endotoxic activity. In particular, the enantiomeric peptides showed potent anti-endotoxic and LPS-neutralizing activities comparable to that of LL-37. Taken together, both a4-W1-E and a4-W2-E holds promise as a template for the development of peptide antibiotics for the treatment of endotoxic shock and sepsis

  4. Prokaryotic Selectivity, Anti-endotoxic Activity and Protease Stability of Diastereomeric and Enantiomeric Analogs of Human Antimicrobial Peptide LL-37

    Energy Technology Data Exchange (ETDEWEB)

    Nan, Yong Hai; Lee, Bongju; Shin, Song Yub [Chosun Univ., Gwangju (Korea, Republic of)

    2012-09-15

    LL-37 is the only antimicrobial peptide (AMP) of the human cathelicidin family. In addition to potent antimicrobial activity, LL-37 is known to have the potential to inhibit lipolysaccharide (LPS)-induced endotoxic effects. To provide the stability to proteolytic digestion and increase prokaryotic selectivity and/or anti-endotoxic activity of two Lys/Trp-substituted 19-meric anti-microbial peptides (a4-W1 and a4-W2) designed from IG-19 (residues 13-31 of LL-37), we synthesized the diastereomeric peptides (a4-W1-D and a4-W2-D) with D-amino acid substitution at positions 3, 7, 10, 13 and 17 of a4-W1 and a4-W2, respectively and the enantiomeric peptides (a4-W1-E and a4-W2-E) composed D-amino acids. The diastereomeric peptides exhibited the best prokaryotic selectivity and effective protease stability, but no or less anti-endotoxic activity. In contrast, the enantiomeric peptides had not only prokaryotic selectivity and anti-endotoxic activity but also protease stability. Our results suggest that the hydrophobicity and α-helicity of the peptide is important for anti-endotoxic activity. In particular, the enantiomeric peptides showed potent anti-endotoxic and LPS-neutralizing activities comparable to that of LL-37. Taken together, both a4-W1-E and a4-W2-E holds promise as a template for the development of peptide antibiotics for the treatment of endotoxic shock and sepsis.

  5. The robust corrective action priority-an improved approach for selecting competing corrective actions in FMEA based on principle of robust design

    Science.gov (United States)

    Sutrisno, Agung; Gunawan, Indra; Vanany, Iwan

    2017-11-01

    In spite of being integral part in risk - based quality improvement effort, studies improving quality of selection of corrective action priority using FMEA technique are still limited in literature. If any, none is considering robustness and risk in selecting competing improvement initiatives. This study proposed a theoretical model to select risk - based competing corrective action by considering robustness and risk of competing corrective actions. We incorporated the principle of robust design in counting the preference score among corrective action candidates. Along with considering cost and benefit of competing corrective actions, we also incorporate the risk and robustness of corrective actions. An example is provided to represent the applicability of the proposed model.

  6. A Hexapod Walker Using a Heterarchical Architecture for Action Selection

    Directory of Open Access Journals (Sweden)

    Malte eSchilling

    2013-09-01

    Full Text Available Moving in a cluttered environment with a six-legged walking machine that has additional body actuators, therefore controlling 22 DoFs, is not a trivial task. Already simple forward walking on a flat plane requires the system to select between different internal states. The orchestration of these states depends on walking velocity and on external disturbances. Such disturbances occur continuously, for example due to irregular up-and-down movements of the body or slipping of the legs, even on flat surfaces, in particular when negotiating tight curves. The number of possible states is further increased when the system is allowed to walk backward or when front legs are used as grippers and cannot contribute to walking. Further states are necessary for expansion that allow for navigation. Here we demonstrate a solution for the selection and sequencing of different (attractor states required to control different behaviors as are forward walking at different speeds, backward walking, as well as negotiation of tight curves. This selection is made by a recurrent neural network of motivation units, controlling a bank of decentralized memory elements in combination with the feedback through the environment. The underlying heterarchical architecture of the network allows to select various combinations of these elements. This modular approach representing an example of neural reuse of a limited number of procedures allows for adaptation to different internal and external conditions. A way is sketched as to how this approach may be expanded to form a cognitive system being able to plan ahead. This architecture is characterized by different types of modules being arranged in layers and columns, but the complete network can also be considered as a holistic system showing emergent properties which cannot be attributed to a specific module.

  7. Antimicrobial, Antioxidant, and Anti-Inflammatory Activities of Essential Oils of Selected Aromatic Plants from Tajikistan

    OpenAIRE

    Sharopov, Farukh; Braun, Markus Santhosh; Gulmurodov, Isomiddin; Khalifaev, Davlat; Isupov, Salomiddin; Wink, Michael

    2015-01-01

    Antimicrobial, antioxidant, and anti-inflammatory activities of the essential oils of 18 plant species from Tajikistan (Central Asia) were investigated. The essential oil of Origanum tyttanthum showed a strong antibacterial activity with both minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 312.5 µg/mL for E. coli, 625 µg/mL (MIC) and 1250 µg/mL (MBC) for MRSA (methicillin-resistant Staphylococcus aureus), respectively. The essential oil of Galagan...

  8. A novel coping metal material CoCrCu alloy fabricated by selective laser melting with antimicrobial and antibiofilm properties

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Ling [Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016 (China); Memarzadeh, Kaveh [Institute of Dentistry, Barts and The London School of Medicine & Dentistry, Queen Mary University of London, Newark Street, London E1 2AT (United Kingdom); Zhang, Shuyuan; Sun, Ziqing; Yang, Chunguang [Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016 (China); Ren, Guogang [University of Hertfordshire, Hatfield AL10 9AB (United Kingdom); Allaker, Robert P., E-mail: r.p.allaker@qmul.ac.uk [Institute of Dentistry, Barts and The London School of Medicine & Dentistry, Queen Mary University of London, Newark Street, London E1 2AT (United Kingdom); Yang, Ke, E-mail: kyang@imr.ac.cn [Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016 (China)

    2016-10-01

    Objective: The aim of this study was to fabricate a novel coping metal CoCrCu alloy using a selective laser melting (SLM) technique with antimicrobial and antibiofilm activities and to investigate its microstructure, mechanical properties, corrosion resistance and biocompatibility. Methods: Novel CoCrCu alloy was fabricated using SLM from a mixture of commercial CoCr based alloy and elemental Cu powders. SLM CoCr without Cu served as control. Antibacterial activity was analyzed using standard antimicrobial tests, and antibiofilm properties were investigated using confocal laser scanning microscope. Cu distribution and microstructure were determined using scanning electron microscope, optical microscopy and X-ray diffraction. Corrosion resistance was evaluated by potential dynamic polarization and biocompatibility measured using an MTT assay. Results: SLM CoCrCu alloys were found to be bactericidal and able to inhibit biofilm formation. Other factors such as microstructure, mechanical properties, corrosion resistance and biocompatibility were similar to those of SLM CoCr alloys. Significance: The addition of appropriate amounts of Cu not only maintains normal beneficial properties of CoCr based alloys, but also provides SLM CoCrCu alloys with excellent antibacterial and antibiofilm capabilities. This material has the potential to be used as a coping metal for dental applications. - Highlights: • Novel CoCrCu alloys were fabricated by using selective laser melting (SLM). • SLM CoCrCu alloys showed satisfied antimicrobial and antibiofilm activities. • SLM CoCrCu alloys have no cytotoxic effect on normal cells. • Other properties of SLM CoCrCu alloys were similar to SLM CoCr alloys. • SLM CoCrCu alloys have the potential to be used as coping metals.

  9. A novel coping metal material CoCrCu alloy fabricated by selective laser melting with antimicrobial and antibiofilm properties

    International Nuclear Information System (INIS)

    Ren, Ling; Memarzadeh, Kaveh; Zhang, Shuyuan; Sun, Ziqing; Yang, Chunguang; Ren, Guogang; Allaker, Robert P.; Yang, Ke

    2016-01-01

    Objective: The aim of this study was to fabricate a novel coping metal CoCrCu alloy using a selective laser melting (SLM) technique with antimicrobial and antibiofilm activities and to investigate its microstructure, mechanical properties, corrosion resistance and biocompatibility. Methods: Novel CoCrCu alloy was fabricated using SLM from a mixture of commercial CoCr based alloy and elemental Cu powders. SLM CoCr without Cu served as control. Antibacterial activity was analyzed using standard antimicrobial tests, and antibiofilm properties were investigated using confocal laser scanning microscope. Cu distribution and microstructure were determined using scanning electron microscope, optical microscopy and X-ray diffraction. Corrosion resistance was evaluated by potential dynamic polarization and biocompatibility measured using an MTT assay. Results: SLM CoCrCu alloys were found to be bactericidal and able to inhibit biofilm formation. Other factors such as microstructure, mechanical properties, corrosion resistance and biocompatibility were similar to those of SLM CoCr alloys. Significance: The addition of appropriate amounts of Cu not only maintains normal beneficial properties of CoCr based alloys, but also provides SLM CoCrCu alloys with excellent antibacterial and antibiofilm capabilities. This material has the potential to be used as a coping metal for dental applications. - Highlights: • Novel CoCrCu alloys were fabricated by using selective laser melting (SLM). • SLM CoCrCu alloys showed satisfied antimicrobial and antibiofilm activities. • SLM CoCrCu alloys have no cytotoxic effect on normal cells. • Other properties of SLM CoCrCu alloys were similar to SLM CoCr alloys. • SLM CoCrCu alloys have the potential to be used as coping metals.

  10. Immediate movement history influences reach-to-grasp action selection in children and adults.

    Science.gov (United States)

    Kent, Samuel W; Wilson, Andrew D; Plumb, Mandy S; Williams, Justin H G; Mon-Williams, Mark

    2009-01-01

    Action selection is subject to many biases. Immediate movement history is one such bias seen in young infants. Is this bias strong enough to affect adult behavior? Adult participants reached and grasped a cylinder positioned to require either pronation or supination of the hand. Successive cylinder positions changed either randomly or systematically between trials. Random positioning led to optimized economy of movement. In contrast, systematic changes in position biased action selection toward previously selected actions at the expense of movement economy. Thus, one switches to a new movement only when the savings outweigh the costs of the switch. Immediate movement history had an even larger influence on children aged 7-15 years. This suggests that switching costs are greater in children, which is consistent with their reduced grasping experience. The presence of this effect in adults suggests that immediate movement history exerts a more widespread and pervasive influence on patterns of action selection than researchers had previously recognized.

  11. Selecting food. The contribution of memory, liking, and action.

    Science.gov (United States)

    Parma, Valentina; Castiello, Umberto; Köster, Egon Peter; Mojet, Jos

    2014-05-01

    The goal of the present experiment was twofold: identifying similarities and differences between flavour memory and visual memory mechanisms and investigating whether kinematics could serve as an implicit measure for food selection. To test flavour and visual memory an 'implicit' paradigm to represent real-life situations in a controlled lab setting was implemented. A target, i.e., a piece of cake shaped like either an orange or a tangerine, covered with either orange- or a tangerine-flavoured icing, was provided to participants on Day 1. On Day 2, without prior notice, participants were requested to recognize the target amongst a set of distractors, characterized by various flavours (orange vs. tangerine) and/or sizes (orange-like vs. tangerine-like). Similarly, targets and distractors consisting of 2D figures varying in shape and size were used to assess visual memory. Reach-to-grasp kinematics towards the targets were recorded and analysed by means of digitalization techniques. Correlations between kinematic parameters, memory and liking for each food item were also calculated. Results concerned with memory recollection indices provided evidence of different key mechanisms which could be based either on novelty of flavour memory or visual memory, respectively. To a moderate extent, kinematics may serve as an implicit index of food selection processes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Detection of Salmonella spp., Candida albicans, Aspergillus spp., and Antimicrobial Residues in Raw and Processed Cow Milk from Selected Smallholder Farms of Zimbabwe

    Directory of Open Access Journals (Sweden)

    Tryness Anastazia Mhone

    2012-01-01

    Full Text Available A cross-sectional study was conducted to detect the presence of Salmonella spp., Candida albicans, Aspergillus spp., and antimicrobial residues in raw milk (n=120 and processed cow milk (n=20 from smallholder dairy farms from three sites in Zimbabwe. Culture and isolation of Salmonella spp., C. albicans, and Aspergillus spp. were performed using selective media, while antimicrobial residues were detected by a dye reduction test. No Salmonella, but C. albicans (17.5%; 21/120, Aspergillus spp. (0.8%; 1/120, and antimicrobial residues (2.5%; 3/120 were detected from raw milk. C. albicans was isolated from all three sites, while Aspergillus spp. and antimicrobial residues were detected from sites 1 and 3, respectively. From processed milk, only C. albicans (5% was isolated while Aspergillus spp. and antimicrobial residues were not detected. These results suggested low prevalence of Salmonella spp. and Aspergillus spp. and a relatively high prevalence of C. albicans in raw milk from the smallholder farms. The potential public health risks of C. albicans and the detected antimicrobial residues need to be considered. Thus, educating farmers on improving milking hygiene and storage of milk and establishing programmes for monitoring antimicrobial residues may help to improve the safety of milk from smallholder farms.

  13. Searching and selecting online information: analysis of the strategic actions of the university students

    OpenAIRE

    María José Hernández Serrano

    2013-01-01

    As complex and dynamic activity, the searching and selection of online information needs a strategic performance in order to achieve effective and meaningful results and processes. The aim of this paper is to analyze whether university students perceive a need to be strategic, for what actions, what times, and what are their predispositions towards the strategic actions in the Internet information searching and selection process. Results showed differences between students by course, thos...

  14. An action selection architecture for autonomous virtual humans in persistent worlds

    OpenAIRE

    Sevin, Etienne de; Thalmann, Daniel

    2007-01-01

    Nowadays, virtual humans such as non-player characters in computer games need to have a strong autonomy in order to live their own life in persistent virtual worlds. When designing autonomous virtual humans, the action selection problem needs to be considered, as it is responsible for decision making at each moment in time. Indeed action selection architectures for autonomous virtual humans need to be reactive, proactive, motivational, and emotional to obtain a high degree of autonomy and ind...

  15. Remedial action selection report Maybell, Colorado, site. Final report

    International Nuclear Information System (INIS)

    1996-12-01

    The Maybell uranium mill tailings site is 25 miles (mi) (40 kilometers [km]) west of the town of Craig, Colorado, in Moffat County, in the northwestern part of the state. The unincorporated town of Maybell is 5 road mi (8 km) southwest of the site. The site is 2.5 mi (4 km) northeast of the Yampa River on relatively flat terrain broken by low, flat-topped mesas. U.S. Highway 40 runs east-west 2 mi (3.2 km) south of the site. The designated site covers approximately 110 acres (ac) (45 hectares [ha]) and consists of a concave-shaped tailings pile and rubble from the demolition of the mill buildings buried in the former mill area. The site is situated between Johnson Wash to the east and Rob Pit Mine to the west. Numerous reclaimed and unreclaimed mines are in the immediate vicinity. Aerial photographs (included at the end of this executive summary) show evidence of mining activity around the Maybell site. Contaminated materials at the Maybell processing site include the tailings pile, which has an average depth of 20 feet (ft) (6 meters [ml]) and contains 2.8 million cubic yards (yd 3 ) (2.1 million cubic meters [m 3 ]) of tailings. The former mill processing area is on the north side of the site and contains 20,000 yd 3 (15,000 m 3 ) of contaminated demolition debris. Off-pile contamination is present and includes areas adjacent to the tailings pile, as well as contamination dispersed by wind and surface water flow. The volume of off-pile contamination to be placed in the disposal cell is 550,000 yd 3 (420,000 m 3 ). The total volume of contaminated materials to be disposed of as part of the remedial action is estimated to be 3.37 million yd 3 (2.58 million m 3 )

  16. The antimicrobial action of resveratrol against Listeria monocytogenes in food-based models and its antibiofilm properties.

    Science.gov (United States)

    Ferreira, Susana; Domingues, Fernanda

    2016-10-01

    Resveratrol (3,5,4'-trihydroxy-trans-stilbene) is a natural phytoalexin synthesized by plants in response to stress. This compound has several beneficial documented properties, namely anti-inflammatory, antioxidant, neuroprotective and antimicrobial activities. In this study the antimicrobial activity of resveratrol against Listeria monocytogenes and Listeria innocua was investigated. Resveratrol had a minimum inhibitory concentration of 200 µg mL(-1) for the tested strains, with time-kill curves demonstrating bacteriostatic activity. Inhibition of biofilm formation was also assessed, with resveratrol strongly inhibiting biofilm formation by both species even at subinhibitory concentrations. Overall, resveratrol showed antimicrobial properties on planktonic cells and on biofilm formation ability. Considering the potential use of resveratrol as a food preservative, the antimicrobial efficacy of resveratrol in food was studied in milk, lettuce leaf model and chicken juice. Resveratrol retained greater efficacy in both lettuce leaf model and chicken juice, but milk had a negative impact on its antilisterial activity, indicating a possible reduction of resveratrol availability in milk. This study reinforces resveratrol as an antimicrobial agent, pointing out its antibiofilm activity and its potential use as preservative in some food matrices. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  17. Traditional medicine in Sakarya province (Turkey) and antimicrobial activities of selected species.

    Science.gov (United States)

    Uzun, Ergin; Sariyar, Günay; Adsersen, Anne; Karakoc, Berna; Otük, Gülten; Oktayoglu, Ercan; Pirildar, Sevda

    2004-12-01

    Traditional medicine in North-West of Turkey (Sakarya province) were studied during a 2 months field study by interviewing local informants from several villages. Plant species used to treat infections were tested for antimicrobial activity. Information was collected for 46 plant species from 30 families and for 5 animal species. Twenty four of the plant species were cultivated. Most used families were Asteraceae, Cucurbitaceae, Lamiaceae and Rosaceae and the most used plants were Artemisia absinthium, Equisetum telmateia, Lavandula stoechas, Melissa officinalis, Tussilago farfara and Urtica dioica. A total of 139 medicinal uses were obtained. Plants are used mainly for infectious diseases (18%), for neurological and psychological disorders (13.7%), cardiovascular disorders (13%), skin disorders (12.2%) and respiratory disorders (10.1%). Extracts were tested in vitro for antimicrobial activity against Staphylococcus aureus ATCC 65538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumonia ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri, Proteus mirabilis and Candida albicans ATCC 10231, using microbroth dilution technique according to National Committee for Clinical Laboratory Standards (NCCLS). This research showed that Arum maculatum, Datura stramonium, Geranium asphodeloides and Equisetum telmateia petroleum ether extracts had MIC values of 39.1 microg/ml, 78.1 microg/ml, 78.1 microg/ml and 39.1 microg/ml, respectively against Staphylococcus epidermidis. Datura stramonium petroleum ether extract had a MIC value of 39.1 microg/ml against Escherichia coli and Trachystemon orientalis ethanol extract had a MIC value of 39.1 microg/ml against Escherichia coli. The antimicrobial activity of Arum maculatum, Equisetum telmateia, Geranium asphodeloides, Plantago intermedia, Senecio vulgaris and Trachystemon orientalis has been reported here for the first time.

  18. Rational Selection and Use of Antimicrobials in Patients with Burn Injuries.

    Science.gov (United States)

    Hill, David M; Sinclair, Scott E; Hickerson, William L

    2017-07-01

    Caring for patients with burn injuries is challenging secondary to the acute disease process, chronic comorbidities, and underrepresentation in evidence-based literature. Much current practice relies on extrapolation of guidance from different patient populations and wide variations in universal practices. Identifying infections or sepsis in this hypermetabolic population is imperfect and often leads to overprescribing of antimicrobials, suboptimal dosing, and multidrug resistance. An understanding of pharmacokinetics and pharmacodynamics may aid optimization of dosing regimens to better attain treatment targets. This article provides an overview of the current status of burn infection and attempts recommendations for consideration to improve universally accepted care. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Studies of the in vitro anticancer, antimicrobial and antioxidant potentials of selected Yemeni medicinal plants from the island Soqotra

    Science.gov (United States)

    2009-01-01

    Background Recent years have witnessed that there is a revival of interest in drug discovery from medicinal plants for the maintenance of health in all parts of the world. The aim of this work was to investigate 26 plants belonging to 17 families collected from a unique place in Yemen (Soqotra Island) for their in vitro anticancer, antimicrobial and antioxidant activities. Methods The 26 plants were extracted with methanol and hot water to yield 52 extracts. Evaluation for in vitro anticancer activity was done against three human cancer cell lines (A-427, 5637 and MCF-7) by using an established microtiter plate assay based on cellular staining with crystal violet. Antimicrobial activity was tested against three Gram-positive bacteria, two Gram-negative bacteria, one yeast species and three multiresistant Staphylococcus strains by using an agar diffusion method and the determination of MIC against three Gram-positive bacteria with the broth micro-dilution assay. Antioxidant activity was investigated by measuring the scavenging activity of the DPPH radical. Moreover, a phytochemical screening of the methanolic extracts was done. Results Notable cancer cell growth inhibition was observed for extracts from Ballochia atro-virgata, Eureiandra balfourii and Hypoestes pubescens, with IC50 values ranging between 0.8 and 8.2 μg/ml. The methanol extracts of Acanthospermum hispidum, Boswellia dioscorides, Boswellia socotrana, Commiphora ornifolia and Euphorbia socotrana also showed noticeable antiproliferative potency with IC50 values 15 mm and MIC values ≤ 250 μg/ml. In addition, the methanolic extracts of Acacia pennivenia, Boswellia dioscorides, Boswellia socotrana and Commiphora ornifolia showed good antioxidant potential at low concentrations (more than 80% at 50 μg/ml). Conclusion Our results show once again that medicinal plants can be promising sources of natural products with potential anticancer, antimicrobial and antioxidative activity. The results will guide

  20. Selective Attention and Control of Action: Comparative Psychology of an Artificial, Evolved Agent and People

    Science.gov (United States)

    Ward, Robert; Ward, Ronnie

    2008-01-01

    This study examined the selective attention abilities of a simple, artificial, evolved agent and considered implications of the agent's performance for theories of selective attention and action. The agent processed two targets in continuous time, catching one and then the other. This task required many cognitive operations, including prioritizing…

  1. Antimicrobial effect of selected lactic acid bacteria against microorganisms with decarboxylase activity

    Directory of Open Access Journals (Sweden)

    Khatantuul Purevdorj

    2017-01-01

    Full Text Available The main purpose of this study was to evaluate the antimicrobial activity of twenty-one bacteriocinogenic lactic acid bacteria (12 strains of Lactococcus lactis subsp. lactis, 4 strains of Lactobacillus gasseri, 3 strains of Lb. helveticus and 2 strains of Lb. acidophilus, LAB against 28 Staphylococcus and 33 Enterococcus strains able to produce tyramine, putrescine, 2-phenylethylamine and cadaverine. The antimicrobial activity of cell-free supernatants (CFS from tested LAB was examined by an agar-well diffusion assay. Nine out of twenty-one strains (33% showed the inhibitory effect on tested enterococci and staphylococci, namely 9 strains of Lactococcus lactis subsp. lactis. The diameters of inhibition zones ranged between 7 mm and 14 mm. The biggest diameter of 14 mm inhibition was obtained with the CFS's from strains CCDM 670 and CCDM 731 on Enterococcus sp. E16 and E28. The cell-free supernatants from Lactococcus lactis subsp. lactis CCDM 71 and from Lactococcus lactis subsp. lactis CCDM 731 displayed the broadest antibacterial activity (52% inhibition of all tested strains. On the other hand, the cell-free supernatants from the screened Lactobacillus strains did not show any inhibitory effect on the tested Staphylococcus and Enterococcus strains. Nowadays, the great attention is given to the antibacterial substances produced by lactic acid bacteria. With the ability to produce a variety of metabolites displaying inhibitory effect, the LAB have great potential in biopreservation of food.

  2. Comparison of antimicrobial activities of natural essential oils and synthetic fragrances against selected environmental pathogens.

    Science.gov (United States)

    Vieira-Brock, Paula L; Vaughan, Brent M; Vollmer, David L

    2017-12-01

    Plant essential oils (EOs) are known to inhibit the growth of bacteria and fungi. Whether these antimicrobial effects are comparable to synthetic household products is less clear. Furthermore, limited research is available on the potential additive effect of blending EOs. In this investigation, a new EO blend containing orange, patchouli, peppermint, and clary sage was compared to its individual single oils and to three household products-air freshener, liquid soap, and body spray-for their ability to inhibit the growth of Staphylococcus aureus, Streptococcus pneumoniae, Pseudonomas aeruginosa, and Aspergillus brasiliensis in the disc-diffusion assay. The new EO blend significantly inhibited the growth of the four microorganisms. The zones of inhibition of new EO blend were greater than the air freshener and similar to the liquid soap and body spray, with the exception of Str. pneumoniae in which the body spray provided greater inhibitory zone. The new EO blend and the single oils, with the exception of peppermint, equally inhibited the growth of S. aureus and Str. pneumoniae suggesting no additive effect. P. aeruginosa and A. brasiliensis showed variable susceptibility to all EOs except for no susceptibility to orange and limonene. No difference was found between (-) and (+)-limonene; whereas, (+)-menthol showed greater effect than (-)-menthol. In conclusion, blending the EO of orange, patchouli, peppermint, and clary sage was beneficial in inhibiting the growth of S. aureus, Str. pneumoniae, P. aeruginosa, and A. brasiliensis providing a natural antimicrobial fragrance option over synthetics fragrances used in soaps, body sprays, and air fresheners.

  3. Antimicrobial, Antioxidant, and Anti-Inflammatory Activities of Essential Oils of Selected Aromatic Plants from Tajikistan

    Directory of Open Access Journals (Sweden)

    Farukh Sharopov

    2015-11-01

    Full Text Available Antimicrobial, antioxidant, and anti-inflammatory activities of the essential oils of 18 plant species from Tajikistan (Central Asia were investigated. The essential oil of Origanum tyttanthum showed a strong antibacterial activity with both minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC values of 312.5 µg/mL for E. coli, 625 µg/mL (MIC and 1250 µg/mL (MBC for MRSA (methicillin-resistant Staphylococcus aureus, respectively. The essential oil of Galagania fragrantissima was highly active against MRSA at concentrations as low as 39.1 µg/mL and 78.2 µg/mL for MIC and MBC, respectively. Origanum tyttanthum essential oil showed the highest antioxidant activity with IC50 values of 0.12 mg/mL for ABTS (2,2′-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid and 0.28 mg/mL for DPPH (2,2-diphenyl-1-picrylhydrazyl. Galagania fragrantissima and Origanum tyttanthum essential oils showed the highest anti-inflammatory activity; IC50 values of 5-lipoxygenase (5-LOX inhibition were 7.34 and 14.78 µg/mL, respectively. In conclusion, essential oils of Origanum tyttanthum and Galagania fragrantissima exhibit substantial antimicrobial, antioxidant, and anti-inflammatory activities. They are interesting candidates in phytotherapy.

  4. In vitro sensitivity of Hungarian Actinobaculum suis strains to selected antimicrobials.

    Science.gov (United States)

    Biksi, I; Major, Andrea; Fodor, L; Szenci, O; Vetési, F

    2003-01-01

    In vitro antimicrobial sensitivity of 12 Hungarian isolates and the type strain ATCC 33144 of Actinobaculum suis to different antimicrobial compounds was determined both by the agar dilution and by the disc diffusion method. By agar dilution, MIC50 values in the range of 0.05-3.125 micrograms/ml were determined for penicillin, ampicillin, ceftiofur, doxycycline, tylosin, pleuromutilins, chloramphenicol, florfenicol, enrofloxacin and lincomycin. The MIC50 value of oxytetracycline and spectinomycin was 6.25 and 12.5 micrograms/ml, respectively. For ofloxacin, flumequine, neomycin, streptomycin, gentamicin, nalidixic acid, nitrofurantoin and sulphamethoxazole + trimethoprim MIC50 values were in the range of 25-100 micrograms/ml. With the disc diffusion method, all strains were sensitive to penicillin, cephalosporins examined, chloramphenicol and florfenicol, tetracyclines examined, pleuromutilins, lincomycin and tylosin. Variable sensitivity was observed for fluoroquinolones (flumequine, enrofloxacin, ofloxacin), most of the strains were susceptible to marbofloxacin. Almost all strains were resistant to aminoglycosides but most of them were sensitive to spectinomycin. A strong correlation was determined for disc diffusion and MIC results (Spearman's rho 0.789, p < 0001). MIC values of the type strain and MIC50 values of other tested strains did not differ significantly. Few strains showed a partially distinct resistance pattern for erythromycin, lincomycin and ampicillin in both methods.

  5. Human Bile Reduces Antimicrobial Activity of Selected Antibiotics against Enterococcus faecalis and Escherichia coli In Vitro.

    Science.gov (United States)

    Wulkersdorfer, Beatrix; Jaros, David; Eberl, Sabine; Poschner, Stefan; Jäger, Walter; Cosentini, Enrico; Zeitlinger, Markus; Schwameis, Richard

    2017-08-01

    It has been known from previous studies that body fluids, such as cerebrospinal fluid, lung surfactant, and urine, have a strong impact on the bacterial killing of many anti-infective agents. However, the influence of human bile on the antimicrobial activity of antibiotics is widely unknown. Human bile was obtained and pooled from 11 patients undergoing cholecystectomy. After sterilization of the bile fluid by gamma irradiation, its effect on bacterial killing was investigated for linezolid (LZD) and tigecycline (TGC) against Enterococcus faecalis ATCC 29212. Further, ciprofloxacin (CIP), meropenem (MEM), and TGC were tested against Escherichia coli ATCC 25922. Time-kill curves were performed in pooled human bile and Mueller-Hinton broth (MHB) over 24 h. Bacterial counts (in CFU per milliliter after 24 h) of bile growth controls were approximately equal to MHB growth controls for E. coli and approximately 2-fold greater for E. faecalis , indicating a promotion of bacterial growth by bile for the latter strain. Bile reduced the antimicrobial activity of CIP, MEM, and TGC against E. coli as well as the activity of LZD and TGC against E. faecalis This effect was strongest for TGC against the two strains. Degradation of TGC in bile was identified as the most likely explanation. These findings may have important implications for the treatment of bacterial infections of the gallbladder and biliary tract and should be explored in more detail. Copyright © 2017 American Society for Microbiology.

  6. Antimicrobial, Antioxidant, and Anti-Inflammatory Activities of Essential Oils of Selected Aromatic Plants from Tajikistan.

    Science.gov (United States)

    Sharopov, Farukh; Braun, Markus Santhosh; Gulmurodov, Isomiddin; Khalifaev, Davlat; Isupov, Salomiddin; Wink, Michael

    2015-11-02

    Antimicrobial, antioxidant, and anti-inflammatory activities of the essential oils of 18 plant species from Tajikistan (Central Asia) were investigated. The essential oil of Origanum tyttanthum showed a strong antibacterial activity with both minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 312.5 µg/mL for E. coli , 625 µg/mL (MIC) and 1250 µg/mL (MBC) for MRSA (methicillin-resistant Staphylococcus aureus), respectively. The essential oil of Galagania fragrantissima was highly active against MRSA at concentrations as low as 39.1 µg/mL and 78.2 µg/mL for MIC and MBC, respectively. Origanum tyttanthum essential oil showed the highest antioxidant activity with IC 50 values of 0.12 mg/mL for ABTS (2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid)) and 0.28 mg/mL for DPPH (2,2-diphenyl-1-picrylhydrazyl) . Galagania fragrantissima and Origanum tyttanthum essential oils showed the highest anti-inflammatory activity; IC 50 values of 5-lipoxygenase (5-LOX) inhibition were 7.34 and 14.78 µg/mL, respectively. In conclusion, essential oils of Origanum tyttanthum and Galagania fragrantissima exhibit substantial antimicrobial, antioxidant, and anti-inflammatory activities. They are interesting candidates in phytotherapy.

  7. Antimicrobial activity of Piper nigrum L. and Cassia didymobotyra L. leaf extract on selected food borne pathogens

    Directory of Open Access Journals (Sweden)

    Mohd. Sayeed Akthar

    2014-09-01

    Full Text Available Objective: To investigate the antimicrobial activity of leaf extract of Piper nigrum (P. nigrum and Cassia didymobotyra (C. didymobotyra (aqueous, methanol, ethanol and petroleum ether against the food borne pathogenic bacteria [Staphylococcus aureus (S. aureus, Escherichia coli (E. coli, Salmonella typhimurium and Pseudomonas aeruginosa] and fungi [Aspergillus spp. and Candida albicans (C. albicans] and also to investigate the presence of various phytochemicals in the leaf extracts of tested plants. Methods: The antimicrobial activity was determined by disc diffusion method. Minimum inhibitory concentration (MIC, minimum bactericidal and fungicidal concentration were determined by serial dilution method. Results: Methanol leaf extract of test plants exhibited greater antimicrobial activity against the selected bacterial and fungal strains. The MIC results showed that ethanol, methanol and petroleum ether leaf extract of P. nigrum inhibited the growth of S. aureus and E. coli at concentration of 12.5 mg/mL. While, ethanol and methanol leaf extracts of C. didymobotyra inhibited the growth of S. aureus at concentration of 6.25 mg/mL. The MIC values for ethanol, methanol and petroleum ether leaf extract of P. nigrum inhibited the growth of C. albicans at concentration of 25.0 mg/mL. While, it was reported that at concentration of 12.5 mg/mL methanol leaf extract of P. nigrum was against the Aspergillus spp. The MIC values of methanol leaf extract of C. didymobotyra inhibited the growth of C. albicans and Aspergillus spp. at concentration of 12.5 mg/mL and 6.25 mg/mL, respectively. The minimum bactericidal concentration of ethanol, methanol leaf extract of P. nigrum for E. coli and ethanol, methanol leaf extract of C. didymobotyra for S. aureus was recorded at concentration 12.5 mg/mL. The minimum fungicidal concentration of ethanol and methanol leaf extract of P. nigrum and C. didymobotyra on C. albicans was recorded at concentration of 25.0 mg

  8. A novel coping metal material CoCrCu alloy fabricated by selective laser melting with antimicrobial and antibiofilm properties.

    Science.gov (United States)

    Ren, Ling; Memarzadeh, Kaveh; Zhang, Shuyuan; Sun, Ziqing; Yang, Chunguang; Ren, Guogang; Allaker, Robert P; Yang, Ke

    2016-10-01

    The aim of this study was to fabricate a novel coping metal CoCrCu alloy using a selective laser melting (SLM) technique with antimicrobial and antibiofilm activities and to investigate its microstructure, mechanical properties, corrosion resistance and biocompatibility. Novel CoCrCu alloy was fabricated using SLM from a mixture of commercial CoCr based alloy and elemental Cu powders. SLM CoCr without Cu served as control. Antibacterial activity was analyzed using standard antimicrobial tests, and antibiofilm properties were investigated using confocal laser scanning microscope. Cu distribution and microstructure were determined using scanning electron microscope, optical microscopy and X-ray diffraction. Corrosion resistance was evaluated by potential dynamic polarization and biocompatibility measured using an MTT assay. SLM CoCrCu alloys were found to be bactericidal and able to inhibit biofilm formation. Other factors such as microstructure, mechanical properties, corrosion resistance and biocompatibility were similar to those of SLM CoCr alloys. The addition of appropriate amounts of Cu not only maintains normal beneficial properties of CoCr based alloys, but also provides SLM CoCrCu alloys with excellent antibacterial and antibiofilm capabilities. This material has the potential to be used as a coping metal for dental applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Helical Antimicrobial Sulfono- {gamma} -AApeptides

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yaqiong; Wu, Haifan; Teng, Peng; Bai, Ge; Lin, Xiaoyang; Zuo, Xiaobing; Cao, Chuanhai; Cai, Jianfeng

    2015-06-11

    Host-defense peptides (HDPs) such as magainin 2 have emerged as potential therapeutic agents combating antibiotic resistance. Inspired by their structures and mechanism of action, herein we report the fi rst example of antimicrobial helical sulfono- γ - AApeptide foldamers. The lead molecule displays broad-spectrum and potent antimicrobial activity against multi-drug-resistant Gram- positive and Gram-negative bacterial pathogens. Time-kill studies and fl uorescence microscopy suggest that sulfono- γ -AApeptides eradicate bacteria by taking a mode of action analogous to that of HDPs. Clear structure - function relationships exist in the studied sequences. Longer sequences, presumably adopting more-de fi ned helical structures, are more potent than shorter ones. Interestingly, the sequence with less helical propensity in solution could be more selective than the stronger helix-forming sequences. Moreover, this class of antimicrobial agents are resistant to proteolytic degradation. These results may lead to the development of a new class of antimicrobial foldamers combating emerging antibiotic-resistant pathogens.

  10. Selection of media for antimicrobial susceptibility testing of fish pathogenic bacteria

    DEFF Research Database (Denmark)

    Dalsgaard, Inger

    2001-01-01

    3, Diagnostic Sensitivity Test Agar) have been used in addition to media (Brain Heart Infusion Agar, Heart Infusion Agar, Columbia Blood Agar) normally utilized for cultivating fastidious bacteria. When testing marine pathogens, sodium chloride or seawater has been included in the media. Media...... pattern in fish pathogenic bacteria. The American guideline from The National Committee for Clinical Laboratory Standards (NCCLS) recommends Mueller-Hinton Agar for susceptibility testing of human pathogens and this validated medium appears to be adequate for the rapidly growing fish pathogens. Following......The available data concerning antimicrobial susceptibility testing of fish pathogens showed that there is no consensus to the basal medium currently being employed. Different media recommended for susceptibility testing of human pathogens (Mueller-Hinton Agar, Tryptone Soya Agar, Antibiotic Medium...

  11. Selection of media for antimicrobial susceptibility testing of fish pathogenic bacteria

    DEFF Research Database (Denmark)

    Dalsgaard, Inger

    2001-01-01

    The available data concerning antimicrobial susceptibility testing of fish pathogens showed that there is no consensus to the basal medium currently being employed. Different media recommended for susceptibility testing of human pathogens (Mueller-Hinton Agar, Tryptone Soya Agar, Antibiotic Medium...... 3, Diagnostic Sensitivity Test Agar) have been used in addition to media (Brain Heart Infusion Agar, Heart Infusion Agar, Columbia Blood Agar) normally utilized for cultivating fastidious bacteria. When testing marine pathogens, sodium chloride or seawater has been included in the media. Media...... normally used for cultivation of pathogens with specific growth requirements like Flavobacterium species and Renibacterium salmoninarum have been used for susceptibility testing. The Mueller-Hinton Agar and different modifications of this medium was used most frequently in published studies on resistant...

  12. Comparison of antimicrobial activities of natural essential oils and synthetic fragrances against selected environmental pathogens

    Directory of Open Access Journals (Sweden)

    Paula L. Vieira-Brock

    2017-12-01

    Full Text Available Plant essential oils (EOs are known to inhibit the growth of bacteria and fungi. Whether these antimicrobial effects are comparable to synthetic household products is less clear. Furthermore, limited research is available on the potential additive effect of blending EOs. In this investigation, a new EO blend containing orange, patchouli, peppermint, and clary sage was compared to its individual single oils and to three household products–air freshener, liquid soap, and body spray–for their ability to inhibit the growth of Staphylococcus aureus, Streptococcus pneumoniae, Pseudonomas aeruginosa, and Aspergillus brasiliensis in the disc-diffusion assay. The new EO blend significantly inhibited the growth of the four microorganisms. The zones of inhibition of new EO blend were greater than the air freshener and similar to the liquid soap and body spray, with the exception of Str. pneumoniae in which the body spray provided greater inhibitory zone. The new EO blend and the single oils, with the exception of peppermint, equally inhibited the growth of S. aureus and Str. pneumoniae suggesting no additive effect. P. aeruginosa and A. brasiliensis showed variable susceptibility to all EOs except for no susceptibility to orange and limonene. No difference was found between (− and (+-limonene; whereas, (+-menthol showed greater effect than (−-menthol. In conclusion, blending the EO of orange, patchouli, peppermint, and clary sage was beneficial in inhibiting the growth of S. aureus, Str. pneumoniae, P. aeruginosa, and A. brasiliensis providing a natural antimicrobial fragrance option over synthetics fragrances used in soaps, body sprays, and air fresheners. Keywords: Essential oils, Soap, Body spray, Air freshener

  13. Antimicrobial polymers.

    Science.gov (United States)

    Jain, Anjali; Duvvuri, L Sailaja; Farah, Shady; Beyth, Nurit; Domb, Abraham J; Khan, Wahid

    2014-12-01

    Better health is basic requirement of human being, but the rapid growth of harmful pathogens and their serious health effects pose a significant challenge to modern science. Infections by pathogenic microorganisms are of great concern in many fields such as medical devices, drugs, hospital surfaces/furniture, dental restoration, surgery equipment, health care products, and hygienic applications (e.g., water purification systems, textiles, food packaging and storage, major or domestic appliances etc.) Antimicrobial polymers are the materials having the capability to kill/inhibit the growth of microbes on their surface or surrounding environment. Recently, they gained considerable interest for both academic research and industry and were found to be better than their small molecular counterparts in terms of enhanced efficacy, reduced toxicity, minimized environmental problems, resistance, and prolonged lifetime. Hence, efforts have focused on the development of antimicrobial polymers with all desired characters for optimum activity. In this Review, an overview of different antimicrobial polymers, their mechanism of action, factors affecting antimicrobial activity, and application in various fields are given. Recent advances and the current clinical status of these polymers are also discussed. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Studies of the antitumor mechanism of action of dermaseptin B2, a multifunctional cationic antimicrobial peptide, reveal a partial implication of cell surface glycosaminoglycans.

    Directory of Open Access Journals (Sweden)

    Célia Dos Santos

    Full Text Available Dermaseptin-B2 (DRS-B2 is a multifunctional cationic antimicrobial peptide (CAP isolated from frog skin secretion. We previously reported that DRS-B2 possesses anticancer and antiangiogenic activities in vitro and in vivo. In the present study, we evaluated the antiproliferative activity of DRS-B2 on numerous tumor cell lines, its cell internalization and studies of its molecular partners as well as their influences on its structure. Confocal microscopy using ([Alexa594]-(Cys0-DRS-B2 shows that in sensitive human tumor cells (PC3, DRS-B2 seems to accumulate rapidly at the cytoplasmic membranes and enters the cytoplasm and the nucleus, while in less sensitive tumor cells (U87MG, DRS-B2 is found packed in vesicles at the cell membrane. Furthermore FACS analysis shows that PC3 cells viability decreases after DRS-B2 treatment while U87 MG seems to be unaffected. However, "pull down" experiments performed with total protein pools from PC3 or U87MG cells and the comparison between the antiproliferative effect of DRS-B2 and its synthetic analog containing all D-amino acids suggest the absence of a stereo-selective protein receptor. Pretreatment of PC3 cells with sodium chlorate, decreases the antiproliferative activity of DRS-B2. This activity is partially restored after addition of exogenous chondroitin sulfate C (CS-C. Moreover, we demonstrate that at nanomolar concentrations CS-C potentiates the antiproliferative effect of DRS-B2. These results highlight the partial implication of glycosaminoglycans in the mechanism of antiproliferative action of DRS-B2. Structural analysis of DRS-B2 by circular dichroism in the presence of increasing concentration of CS-C shows that DRS-B2 adopts an α-helical structure. Finally, structure-activity-relationship studies suggest a key role of the W residue in position 3 of the DRS-B2 sequence for its antiproliferative activity.

  15. Properties of Neurons in External Globus Pallidus Can Support Optimal Action Selection

    Science.gov (United States)

    Bogacz, Rafal; Martin Moraud, Eduardo; Abdi, Azzedine; Magill, Peter J.; Baufreton, Jérôme

    2016-01-01

    The external globus pallidus (GPe) is a key nucleus within basal ganglia circuits that are thought to be involved in action selection. A class of computational models assumes that, during action selection, the basal ganglia compute for all actions available in a given context the probabilities that they should be selected. These models suggest that a network of GPe and subthalamic nucleus (STN) neurons computes the normalization term in Bayes’ equation. In order to perform such computation, the GPe needs to send feedback to the STN equal to a particular function of the activity of STN neurons. However, the complex form of this function makes it unlikely that individual GPe neurons, or even a single GPe cell type, could compute it. Here, we demonstrate how this function could be computed within a network containing two types of GABAergic GPe projection neuron, so-called ‘prototypic’ and ‘arkypallidal’ neurons, that have different response properties in vivo and distinct connections. We compare our model predictions with the experimentally-reported connectivity and input-output functions (f-I curves) of the two populations of GPe neurons. We show that, together, these dichotomous cell types fulfil the requirements necessary to compute the function needed for optimal action selection. We conclude that, by virtue of their distinct response properties and connectivities, a network of arkypallidal and prototypic GPe neurons comprises a neural substrate capable of supporting the computation of the posterior probabilities of actions. PMID:27389780

  16. Antimicrobial susceptibility survey of pathogens isolated from selected patients in Northern Italy

    Directory of Open Access Journals (Sweden)

    Elisabetta Maioli

    2005-03-01

    Full Text Available The Clinical Microbiology Laboratory of the University of Genoa participated, during the year 2003, in an international antimicrobial surveillance program.The collection of isolates was done according to the site of infection and/or type of patient. Four hundred twenty (420 clinical isolates were analyzed during this year and the frequencies of the different pathogens were investigated. A reference centre carried out susceptibility tests. Oxacillin-resistant Staphylococcus aureus represented 47.6% of all S. aureus isolates from blood stream infections and 33.3% of all S. aureus isolated from skin and soft tissue infections in hospitalised patients.These strains showed resistance to most of the antimicrobial agents evaluated, except vancomycin, teicoplanin, quinupristin/dalfopristin and linezolid which registered 100% of susceptibility. Some isolates from blood stream infections such as E. coli demonstrated resistance to ciprofloxacin (23.3%, levofloxacin (20%, and gatifloxacin (16.6%, and Klebsiella pneumoniae was resistant (18% to all fluoroquinolones tested. Pseudomonas aeruginosa manifested resistance to ciprofloxacin (16.6%, while 27.7% of these strains were resistant both to levofloxacin and gatifloxacin. All the Enterobacter cloacae isolated from blood were susceptible to ciprofloxacin, levofloxacin and gatifloxacin. Haemophilus influenzae and Moraxella catarrhalis collected from community-acquired respiratory tract infections were all inhibited by ciprofloxacin, levofloxacin and gatifloxacin. E. coli isolated from urinary tract infections in hospitalised patients were resistant to ciprofloxacin, levofloxacin and gatifloxacin (2.7%. All Salmonella spp. collected from samples of patients affected by infections of the gastro-intestinal tract were susceptible to all fluoroquinolones. Penicillin resistance in Streptococcus pneumoniae was found in 21.4% of isolates from patients with respiratory tract infections. Fluoroquinolone resistance was

  17. Chronic alcohol exposure disrupts top-down control over basal ganglia action selection to produce habits.

    Science.gov (United States)

    Renteria, Rafael; Baltz, Emily T; Gremel, Christina M

    2018-01-15

    Addiction involves a predominance of habitual control mediated through action selection processes in dorsal striatum. Research has largely focused on neural mechanisms mediating a proposed progression from ventral to dorsal lateral striatal control in addiction. However, over reliance on habit striatal processes may also arise from reduced cortical input to striatum, thereby disrupting executive control over action selection. Here, we identify novel mechanisms through which chronic intermittent ethanol exposure and withdrawal (CIE) disrupts top-down control over goal-directed action selection processes to produce habits. We find CIE results in decreased excitability of orbital frontal cortex (OFC) excitatory circuits supporting goal-directed control, and, strikingly, selectively reduces OFC output to the direct output pathway in dorsal medial striatum. Increasing the activity of OFC circuits restores goal-directed control in CIE-exposed mice. Our findings show habitual control in alcohol dependence can arise through disrupted communication between top-down, goal-directed processes onto basal ganglia pathways controlling action selection.

  18. Structure-activity relationships of the antimicrobial peptide arasin 1 - and mode of action studies of the N-terminal, proline-rich region.

    Directory of Open Access Journals (Sweden)

    Victoria S Paulsen

    Full Text Available Arasin 1 is a 37 amino acid long proline-rich antimicrobial peptide isolated from the spider crab, Hyas araneus. In this work the active region of arasin 1 was identified through structure-activity studies using different peptide fragments derived from the arasin 1 sequence. The pharmacophore was found to be located in the proline/arginine-rich NH(2 terminus of the peptide and the fragment arasin 1(1-23 was almost equally active to the full length peptide. Arasin 1 and its active fragment arasin 1(1-23 were shown to be non-toxic to human red blood cells and arasin 1(1-23 was able to bind chitin, a component of fungal cell walls and the crustacean shell. The mode of action of the fully active N-terminal arasin 1(1-23 was explored through killing kinetic and membrane permeabilization studies. At the minimal inhibitory concentration (MIC, arasin 1(1-23 was not bactericidal and had no membrane disruptive effect. In contrast, at concentrations of 5×MIC and above it was bactericidal and interfered with membrane integrity. We conclude that arasin 1(1-23 has a different mode of action than lytic peptides, like cecropin P1. Thus, we suggest a dual mode of action for arasin 1(1-23 involving membrane disruption at peptide concentrations above MIC, and an alternative mechanism of action, possibly involving intracellular targets, at MIC.

  19. The mathematics of random mutation and natural selection for multiple simultaneous selection pressures and the evolution of antimicrobial drug resistance.

    Science.gov (United States)

    Kleinman, Alan

    2016-12-20

    The random mutation and natural selection phenomenon act in a mathematically predictable behavior, which when understood leads to approaches to reduce and prevent the failure of the use of these selection pressures when treating infections and cancers. The underlying principle to impair the random mutation and natural selection phenomenon is to use combination therapy, which forces the population to evolve to multiple selection pressures simultaneously that invoke the multiplication rule of probabilities simultaneously as well. Recently, it has been seen that combination therapy for the treatment of malaria has failed to prevent the emergence of drug-resistant variants. Using this empirical example and the principles of probability theory, the derivation of the equations describing this treatment failure is carried out. These equations give guidance as to how to use combination therapy for the treatment of cancers and infectious diseases and prevent the emergence of drug resistance. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  20. Antimicrobial activity of Paepalanthus planifolius and its major components against selected human pathogens

    International Nuclear Information System (INIS)

    Amorim, Marcelo R. de; Hilário, Felipe; Bauab, Tais M.; Santos, Lourdes C. dos; Sano, Paulo T.

    2018-01-01

    The chemical investigation of ethyl acetate extract from Paepalanthus planifolius capitula resulted in the identification of 1H-naphtho[2,3-c]pyran-1-one,9-[(6-O-β-D-glucopyranosyl- β-D-glucopyranosyl)oxy]-3,4-dihydro-10-hydroxy-7-methoxy-3-methyl, semi-vioxanthin 9-O-β-D-glucopyranoside, toralactone-9-O-β-D-glucopyranoside, paepalantine9-O-β-D-glucopyranoside, semi-vioxanthin, 1 H-naphtho[2,3-c]pyran-1-one,3,4-dihydro-9,10-dihydroxy-5,7-dimethoxy- 3-methyl, vioxanthin and paepalantine dimer, and also the isolation and identification of a new naphthopyranone dimer named planifoliusin A. The chemical structures of two compounds were elucidated by performing spectroscopic 1D and 2D nuclear magnetic resonance (NMR) experiments and spectrometric HRMS (high-resolution mass spectrometry) analysis. Other six naphthopyranone dimers were proposed by MS fragmentation patterns. The minimum inhibitory concentration (MIC) values for vioxanthin (7.8 μg mL -1 ), planifoliusin A (15.6 μg mL -1 ) and the ethyl acetate extract (31.2 μg mL -1 ) showed antimicrobial activity against Staphylococcus aureus (ATCC 25923). (author)

  1. Antimicrobial activity of Paepalanthus planifolius and its major components against selected human pathogens

    Energy Technology Data Exchange (ETDEWEB)

    Amorim, Marcelo R. de; Hilário, Felipe; Bauab, Tais M.; Santos, Lourdes C. dos [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Araraquara, SP (Brazil); Sano, Paulo T., E-mail: loursant@gmail.com [Universidade de São Paulo (USP), São Paulo, SP (Brazil)

    2018-05-01

    The chemical investigation of ethyl acetate extract from Paepalanthus planifolius capitula resulted in the identification of 1H-naphtho[2,3-c]pyran-1-one,9-[(6-O-β-D-glucopyranosyl- β-D-glucopyranosyl)oxy]-3,4-dihydro-10-hydroxy-7-methoxy-3-methyl, semi-vioxanthin 9-O-β-D-glucopyranoside, toralactone-9-O-β-D-glucopyranoside, paepalantine9-O-β-D-glucopyranoside, semi-vioxanthin, {sup 1}H-naphtho[2,3-c]pyran-1-one,3,4-dihydro-9,10-dihydroxy-5,7-dimethoxy- 3-methyl, vioxanthin and paepalantine dimer, and also the isolation and identification of a new naphthopyranone dimer named planifoliusin A. The chemical structures of two compounds were elucidated by performing spectroscopic 1D and 2D nuclear magnetic resonance (NMR) experiments and spectrometric HRMS (high-resolution mass spectrometry) analysis. Other six naphthopyranone dimers were proposed by MS fragmentation patterns. The minimum inhibitory concentration (MIC) values for vioxanthin (7.8 μg mL{sup -1}), planifoliusin A (15.6 μg mL{sup -1}) and the ethyl acetate extract (31.2 μg mL{sup -1}) showed antimicrobial activity against Staphylococcus aureus (ATCC 25923). (author)

  2. Studies of the in vitro anticancer, antimicrobial and antioxidant potentials of selected Yemeni medicinal plants from the island Soqotra

    Directory of Open Access Journals (Sweden)

    Bednarski Patrick J

    2009-03-01

    at low concentrations (more than 80% at 50 μg/ml. Conclusion Our results show once again that medicinal plants can be promising sources of natural products with potential anticancer, antimicrobial and antioxidative activity. The results will guide the selection of some plant species for further pharmacological and phytochemical investigations.

  3. Multiple bottlenecks in hierarchical control of action sequences: what does "response selection" select in skilled typewriting?

    Science.gov (United States)

    Yamaguchi, Motonori; Logan, Gordon D; Li, Vanessa

    2013-08-01

    Does response selection select words or letters in skilled typewriting? Typing performance involves hierarchically organized control processes: an outer loop that controls word level processing, and an inner loop that controls letter (or keystroke) level processing. The present study addressed whether response selection occurs in the outer loop or the inner loop by using the psychological refractory period (PRP) paradigm in which Task1 required typing single words and Task2 required vocal responses to tones. The number of letters (string length) in the words was manipulated to discriminate selection of words from selection of keystrokes. In Experiment 1, the PRP effect depended on string length of words in Task1, suggesting that response selection occurs in the inner loop. To assess contributions of the outer loop, the influence of string length was examined in a lexical-decision task that also involves word encoding and lexical access (Experiment 2), or to-be-typed words were preexposed so outer-loop processing could finish before typing started (Experiment 3). Response time for Task2 (RT2) did not depend on string length with lexical decision, and RT2 still depended on string length with typing preexposed strings. These results support the inner-loop locus of the PRP effect. In Experiment 4, typing was performed as Task2, and the effect of string length on typing RT interacted with stimulus onset asynchrony superadditively, implying that another bottleneck also exists in the outer loop. We conclude that there are at least two bottleneck processes in skilled typewriting. 2013 APA, all rights reserved

  4. Use of an action-selection framework for human-carnivore conflict in the Bangladesh Sundarbans.

    Science.gov (United States)

    Barlow, Adam C D; Greenwood, Christina J; Ahmad, Ishtiaq U; Smith, James L D

    2010-10-01

    Human-carnivore conflict is manifested in the death of humans, livestock, and carnivores. The resulting negative local attitudes and retribution killings imperil the future of many endangered carnivores. We tailored existing management tools to create a framework to facilitate the selection of actions to alleviate human-carnivore conflict and applied the framework to the human-tiger conflict in the Bangladesh Sundarbans. We identified potential actions that consider previous management efforts, local knowledge, cost-effectiveness, fieldwork experience of authors and project staff, previous research on tiger ecology by the authors, and recommendations from human-carnivore conflict studies in other countries. Our framework includes creation of a profile to improve understanding of the nature of the conflict and its underlying causality. Identified actions include deterrents, education, direct tiger management, and response teams. We ranked actions by their potential to reduce conflict and the monetary cost of their implementation. We ranked tiger-response teams and monitoring problem tigers as the two best actions because both had relatively high impact and cost-effectiveness. We believe this framework could be used under a wide range of human-wildlife conflict situations because it provides a structured approach to selection of mitigating actions. © 2010 Society for Conservation Biology.

  5. Increased dependence of action selection on recent motor history in Parkinson's disease.

    NARCIS (Netherlands)

    Helmich, R.C.G.; Aarts, E.; Lange, F.P. de; Bloem, B.R.; Toni, I.

    2009-01-01

    It is well known that the basal ganglia are involved in switching between movement sequences. Here we test the hypothesis that this contribution is an instance of a more general role of the basal ganglia in selecting actions that deviate from the context defined by the recent motor history, even

  6. Increased Dependence of Action Selection on Recent Motor History in Parkinson's Disease

    NARCIS (Netherlands)

    Helmich, R.C.G.; Aarts, E.; Lange, F.P. de; Bloem, B.R.; Toni, I.

    2009-01-01

    It is well known that the basal ganglia are involved in switching between movement sequences. Here we test the hypothesis that this contribution is an instance of a more general role of the basal ganglia in selecting actions that deviate from the context defined by the recent motor history, even

  7. Pharmacokinetic-pharmacodynamic (PK-PD) modeling and the rational selection of dosage regimes for the prudent use of antimicrobial drugs.

    Science.gov (United States)

    Papich, Mark G

    2014-07-16

    One of the strategies to decrease inappropriate antimicrobial use in veterinary medicine is to apply pharmacokinetic-pharmacodynamic (PK-PD) principles to dosing regimens. If antimicrobials are used appropriately by applying these principles to attain targets for area-under-the-curve to MIC ratio (AUC/MIC), peak concentration to MIC ratio (CMAX/MIC), and time above MIC (T>MIC), more effective antibiotic therapy is possible, thus avoiding ineffective administration. Another mechanism whereby inappropriate antibiotic administration can be avoided is to use accurate Interpretive Criteria established by the Clinical Laboratory Standards Institute (CLSI) for breakpoint selection. Inaccurate breakpoints will encourage antibiotic administration that is likely to be ineffective. For newly approved antimicrobials, three criteria are used for determining breakpoints: PK-PD criteria, MIC distributions, and clinical response. For older (often generic drugs) evaluated by the CLSI, recent clinical data may not be available and breakpoints are derived from PK-PD principles, wild-type distributions, and Monte Carlo simulations. It is the goal of the CLSI subcommittee that these revised breakpoints will encourage more effective antimicrobial use and avoid unnecessary antimicrobial administration. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Corticostriatal circuit mechanisms of value-based action selection: Implementation of reinforcement learning algorithms and beyond.

    Science.gov (United States)

    Morita, Kenji; Jitsev, Jenia; Morrison, Abigail

    2016-09-15

    Value-based action selection has been suggested to be realized in the corticostriatal local circuits through competition among neural populations. In this article, we review theoretical and experimental studies that have constructed and verified this notion, and provide new perspectives on how the local-circuit selection mechanisms implement reinforcement learning (RL) algorithms and computations beyond them. The striatal neurons are mostly inhibitory, and lateral inhibition among them has been classically proposed to realize "Winner-Take-All (WTA)" selection of the maximum-valued action (i.e., 'max' operation). Although this view has been challenged by the revealed weakness, sparseness, and asymmetry of lateral inhibition, which suggest more complex dynamics, WTA-like competition could still occur on short time scales. Unlike the striatal circuit, the cortical circuit contains recurrent excitation, which may enable retention or temporal integration of information and probabilistic "soft-max" selection. The striatal "max" circuit and the cortical "soft-max" circuit might co-implement an RL algorithm called Q-learning; the cortical circuit might also similarly serve for other algorithms such as SARSA. In these implementations, the cortical circuit presumably sustains activity representing the executed action, which negatively impacts dopamine neurons so that they can calculate reward-prediction-error. Regarding the suggested more complex dynamics of striatal, as well as cortical, circuits on long time scales, which could be viewed as a sequence of short WTA fragments, computational roles remain open: such a sequence might represent (1) sequential state-action-state transitions, constituting replay or simulation of the internal model, (2) a single state/action by the whole trajectory, or (3) probabilistic sampling of state/action. Copyright © 2016. Published by Elsevier B.V.

  9. Nuclear facility decommissioning and site remedial actions: A selected bibliography, Volume 12

    International Nuclear Information System (INIS)

    1991-09-01

    The 664 abstracted references on environmental restoration, nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the twelfth in a series of reports prepared annually for the US Department of Energy Remedial Action Programs. Citations to foreign and domestic literature of all types -- technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions -- have been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of Energy Remedial Action Programs. Major sections are (1) Decontamination and Decommissioning Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Program, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Uranium Mill Tailings Management, (7) Technical Measurements Center, and (8) Environmental Restoration Program. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication title. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, subject category, and key word. This report is a product of the Remedial Action Program Information Center (RAPIC), which selects, analyzes, and disseminates information on environmental restoration and remedial actions. RAPIC staff and resources are available to meet a variety of information needs. Contact the center at FTS 624-7764 or (615) 574-7764

  10. Where and how to manage: Optimal selection of conservation actions for multiple species.

    Directory of Open Access Journals (Sweden)

    Astrid van Teeffelen

    2008-01-01

    Full Text Available Multiple alternative options are frequently available for the protection, maintenance or restoration of conservation areas. The choice of a particular management action can have large effects on the species occurring in the area, because different actions have different effects on different species. Together with the fact that conservation funds are limited and particular management actions are costly, it would be desirable to be able to identify where, and what kind of management should be applied to maximize conservation benefits. Currently available site-selection algorithms can identify the optimal set of sites for a reserve network. However, these algorithms have not been designed to answer what kind of action would be most beneficial at these sites when multiple alternative actions are available. We describe an algorithm capable of solving multi-species planning problems with multiple management options per site. The algorithm is based on benefit functions, which translate the effect of a management action on species representation levels into a value, in order to identify the most beneficial option. We test the performance of this algorithm with simulated data for different types of benefit functions and show that the algorithm’s solutions are optimal, or very near globally optimal, partially depending on the type of benefit function used. The good performance of the proposed algorithm suggests that it could be profitably used for large multi-action multi-species conservation planning problems.

  11. Nuclear facility decommissioning and site remedial actions: A selected bibliography, Volume 12. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    1991-09-01

    The 664 abstracted references on environmental restoration, nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the twelfth in a series of reports prepared annually for the US Department of Energy Remedial Action Programs. Citations to foreign and domestic literature of all types -- technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions -- have been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of Energy Remedial Action Programs. Major sections are (1) Decontamination and Decommissioning Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Program, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Uranium Mill Tailings Management, (7) Technical Measurements Center, and (8) Environmental Restoration Program. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication title. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, subject category, and key word. This report is a product of the Remedial Action Program Information Center (RAPIC), which selects, analyzes, and disseminates information on environmental restoration and remedial actions. RAPIC staff and resources are available to meet a variety of information needs. Contact the center at FTS 624-7764 or (615) 574-7764.

  12. Nuclear facility decommissioning and site remedial actions: A selected bibliography, Volume 12

    Energy Technology Data Exchange (ETDEWEB)

    Owen, P. T.; Webb, J. R.; Knox, N. P.; Goins, L. F.; Harrell, R. E.; Mallory, P. K.; Cravens, C. D.

    1991-09-01

    The 664 abstracted references on environmental restoration, nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the twelfth in a series of reports prepared annually for the US Department of Energy Remedial Action Programs. Citations to foreign and domestic literature of all types -- technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions -- have been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of Energy Remedial Action Programs. Major sections are (1) Decontamination and Decommissioning Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Program, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Uranium Mill Tailings Management, (7) Technical Measurements Center, and (8) Environmental Restoration Program. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication title. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, subject category, and key word. This report is a product of the Remedial Action Program Information Center (RAPIC), which selects, analyzes, and disseminates information on environmental restoration and remedial actions. RAPIC staff and resources are available to meet a variety of information needs. Contact the center at FTS 624-7764 or (615) 574-7764.

  13. Epidemiology of Antibiotic Use and Antimicrobial Resistance in Selected Communities in Thailand.

    Science.gov (United States)

    Khamsarn, Sompong; Nampoonsak, Yupin; Busamaro, Supunnee; Tangkoskul, Teerawit; Seenama, Chakkraphong; Rattanaumpawan, Pinyo; Boonyasiri, Adhiratha; Thamlikitkul, Visanu

    2016-03-01

    To generate epidemiological information regarding antibiotic use and antimicrobial resistance (AMR) in targeted communities for use by the Thailand AMR Containment and Prevention Program. A survey of antibiotics sold by 215 grocery stores and retail shops located in the target communities was done by the local people who were instructed to purchase specified antibiotics and to present to such stores and shops with symptoms of sore throat, backache, common cold, acute diarrhea, inflamed uterus, and dysuria. The purchased drugs were then identified and recorded. Contamination of extended-spectrum β-lactamase (ESBL)-producing E. coli was identified in 174 samples of foods and open water sources collected from the target communities. Carriage of ESBL-producing E. coli in gastrointestinal tracts of 534 adults living in the target communities was performed by stool sample culture. One thousand three hundred one patients with upper respiratory infection (URI) and 235 patients with acute diarrhea who attended the tambon health promoting hospitals located in the target communities were monitored for their clinical outcomes of treatments. The patients with URI and acute diarrhea with no indication of antibiotic received symptomatic treatments as appropriate and they were followed via telephone contact every few days until all symptoms related to URI and acute diarrhea disappeared. The data were analyzed by descriptive statistics. Antibiotics were sold to the local people who were presenting with common ailments at many grocery stores and retail shops in their respective communities. In almost all cases, antibiotics were inappropriately given. Overall prevalence of ESBL-producing E. coli contamination in foods and open water sources was 26.4%. ESBL-producing E. coli was isolated from fresh meat and open water sources in many samples. Overall prevalence of ESBL-producing E. coli carriage in gastrointestinal tracts of the adults cultured was 66.5%. All patients with URI and

  14. Nuclear facility decommissioning and site remedial actions: A selected bibliography, volume 9

    Energy Technology Data Exchange (ETDEWEB)

    Owen, P.T.; Knox, N.P.; Michelson, D.C.; Turmer, G.S.

    1988-09-01

    The 604 abstracted references on nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the ninth in a series of reports prepared annually for the US Department of Energy's Remedial Action Programs. Foreign and domestic literature of all types--technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions--has been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of Energy's remedial action programs. Major sections are (1) Surplus Facilities Management Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Program, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Uranium Mill Tailings Management, (7) Technical Measurements Center, and (8) General Remedial Action Program Studies. Subsections for sections 1, 2, 5, and 6 include: Design, Planning, and Regulations; Environmental Studies and Site Surveys; Health, Safety, and Biomedical Studies; Decontamination Studies; Dismantlement and Demolition; Site Stabilization and Reclamation; Waste Disposal; Remedial Action Experience; and General Studies. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication description. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, and keywords. This report is a product of the Remedial Action Program Information Center (RAPIC), which selects and analyzes information on remedial actions and relevant radioactive waste management technologies. RAPIC staff and resources are available to meet a variety of information needs. Contact the center at (615) 576-0568 or FTS 626-0568.

  15. Nuclear facility decommissioning and site remedial actions: A selected bibliography, volume 9

    International Nuclear Information System (INIS)

    Owen, P.T.; Knox, N.P.; Michelson, D.C.; Turmer, G.S.

    1988-09-01

    The 604 abstracted references on nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the ninth in a series of reports prepared annually for the US Department of Energy's Remedial Action Programs. Foreign and domestic literature of all types--technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions--has been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of Energy's remedial action programs. Major sections are (1) Surplus Facilities Management Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Program, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Uranium Mill Tailings Management, (7) Technical Measurements Center, and (8) General Remedial Action Program Studies. Subsections for sections 1, 2, 5, and 6 include: Design, Planning, and Regulations; Environmental Studies and Site Surveys; Health, Safety, and Biomedical Studies; Decontamination Studies; Dismantlement and Demolition; Site Stabilization and Reclamation; Waste Disposal; Remedial Action Experience; and General Studies. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication description. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, and keywords. This report is a product of the Remedial Action Program Information Center (RAPIC), which selects and analyzes information on remedial actions and relevant radioactive waste management technologies. RAPIC staff and resources are available to meet a variety of information needs. Contact the center at (615) 576-0568 or FTS 626-0568

  16. Antimicrobial activity and probable mechanisms of action of medicinal plants of Kenya: Withania somnifera, Warbugia ugandensis, Prunus africana and Plectrunthus barbatus.

    Directory of Open Access Journals (Sweden)

    Peter G Mwitari

    Full Text Available Withania somnifera, Warbugia ugandensis, Prunus africana and Plectrunthus barbatus are used traditionally in Kenya for treatment of microbial infections and cancer. Information on their use is available, but scientific data on their bioactivity, safety and mechanisms of action is still scanty. A study was conducted on the effect of organic extracts of these plants on both bacterial and fungal strains, and their mechanisms of action. Extracts were evaluated through the disc diffusion assay. Bacteria and yeast test strains were cultured on Mueller-Hinton agar and on Sabouraud dextrose agar for the filamentous fungi. A 0.5 McFarland standard suspension was prepared. Sterile paper discs 6 mm in diameter impregnated with 10 µl of the test extract (100 mg/ml were aseptically placed onto the surface of the inoculated media. Chloramphenicol (30 µg and fluconazole (25 µg were used as standards. Discs impregnated with dissolution medium were used as controls. Activity of the extracts was expressed according to zone of inhibition diameter. MIC was determined at 0.78-100 mg/ml. Safety studies were carried using Cell Counting Kit 8 cell proliferation assay protocol. To evaluate extracts mechanisms of action, IEC-6 cells and RT-PCR technique was employed in vitro to evaluate Interleukin 7 cytokine. Investigated plants extracts have both bactericidal and fungicidal activity. W. ugandensis is cytotoxic at IC50200 µg/ml. Fractions from W. ugandensis and W. somnifera too demonstrated antimicrobial activity. Mechanisms of action can largely be attributed to cytotoxicity, Gene silencing and immunopotentiation. Use of medicinal plants in traditional medicine has been justified and possible mechanisms of action demonstrated. Studies to isolate and characterize the bioactive constituents continue.

  17. A Biologically Inspired Computational Model of Basal Ganglia in Action Selection.

    Science.gov (United States)

    Baston, Chiara; Ursino, Mauro

    2015-01-01

    The basal ganglia (BG) are a subcortical structure implicated in action selection. The aim of this work is to present a new cognitive neuroscience model of the BG, which aspires to represent a parsimonious balance between simplicity and completeness. The model includes the 3 main pathways operating in the BG circuitry, that is, the direct (Go), indirect (NoGo), and hyperdirect pathways. The main original aspects, compared with previous models, are the use of a two-term Hebb rule to train synapses in the striatum, based exclusively on neuronal activity changes caused by dopamine peaks or dips, and the role of the cholinergic interneurons (affected by dopamine themselves) during learning. Some examples are displayed, concerning a few paradigmatic cases: action selection in basal conditions, action selection in the presence of a strong conflict (where the role of the hyperdirect pathway emerges), synapse changes induced by phasic dopamine, and learning new actions based on a previous history of rewards and punishments. Finally, some simulations show model working in conditions of altered dopamine levels, to illustrate pathological cases (dopamine depletion in parkinsonian subjects or dopamine hypermedication). Due to its parsimonious approach, the model may represent a straightforward tool to analyze BG functionality in behavioral experiments.

  18. A Biologically Inspired Computational Model of Basal Ganglia in Action Selection

    Directory of Open Access Journals (Sweden)

    Chiara Baston

    2015-01-01

    Full Text Available The basal ganglia (BG are a subcortical structure implicated in action selection. The aim of this work is to present a new cognitive neuroscience model of the BG, which aspires to represent a parsimonious balance between simplicity and completeness. The model includes the 3 main pathways operating in the BG circuitry, that is, the direct (Go, indirect (NoGo, and hyperdirect pathways. The main original aspects, compared with previous models, are the use of a two-term Hebb rule to train synapses in the striatum, based exclusively on neuronal activity changes caused by dopamine peaks or dips, and the role of the cholinergic interneurons (affected by dopamine themselves during learning. Some examples are displayed, concerning a few paradigmatic cases: action selection in basal conditions, action selection in the presence of a strong conflict (where the role of the hyperdirect pathway emerges, synapse changes induced by phasic dopamine, and learning new actions based on a previous history of rewards and punishments. Finally, some simulations show model working in conditions of altered dopamine levels, to illustrate pathological cases (dopamine depletion in parkinsonian subjects or dopamine hypermedication. Due to its parsimonious approach, the model may represent a straightforward tool to analyze BG functionality in behavioral experiments.

  19. What motivates participation in violent political action: selective incentives or parochial altruism?

    Science.gov (United States)

    Ginges, Jeremy; Atran, Scott

    2009-06-01

    In standard models of decision making, participation in violent political action is understood as the product of instrumentally rational reasoning. According to this line of thinking, instrumentally rational individuals will participate in violent political action only if there are selective incentives that are limited to participants. We argue in favor of an alternate model of political violence where participants are motivated by moral commitments to collective sacred values. Correlative and experimental empirical evidence in the context of the Israeli-Palestinian conflict strongly supports this alternate view.

  20. Interference of the antimicrobial peptide lactoferricin B with the action of various antibiotics against Escherichia coli and Staphylococcus aureus.

    Science.gov (United States)

    Vorland, L H; Osbakk, S A; Perstølen, T; Ulvatne, H; Rekdal, O; Svendsen, J S; Gutteberg, T J

    1999-01-01

    The antimicrobial peptide, lactoferricin, can be generated upon gastric pepsin cleavage of lactoferrin. We have examined the interaction of lactoferricin of bovine origin, Lf-cin B, with the antibiotics penicillin G, vancomycin, gentamicin, colistin, D-cycloserine and erythromycin against E. coli ATCC 25922 and Staphylococcus aureus ATCC 25923. We demonstrated synergism between Lf-cin B and erythromycin against E. coli, and partial synergism between Lf-cin B and penicillin G, vancomycin and gentamicin against E. coli. Only penicillin G acted in partial synergism with Lf-cin B against S. aureus. Lf-cin B antagonized vancomycin and gentamicin against S. aureus in low concentration. We conclude that Lf-cin B may facilitate the uptake of antibiotics across the cell envelope.

  1. Resistance and Tolerance to Tropodithietic Acid, an Antimicrobial in Aquaculture, Is Hard To Select

    DEFF Research Database (Denmark)

    Porsby, Cisse Hedegaard; Webber, Mark A.; Nielsen, Kristian Fog

    2011-01-01

    of development of TDA resistance. A bacterial extract containing 95% TDA was effective against a range of human-pathogenic bacteria, including both Gram-negative and Gram-positive bacteria. TDA was bactericidal against Salmonella enterica serovar Typhimurium SL1344 and Staphylococcus aureus NCTC 12493 and killed...... mutants, or prolonged exposure to incremental concentrations of TDA) resulted in resistant or tolerant strains. After more than 300 generations exposed to sub-MIC and MIC concentrations of a TDA-containing extract, strains tolerant to 2x the MIC of TDA for wild-type strains were selected...... both growing and nongrowing cells. Several experimental approaches were used to select mutants resistant to TDA or subpopulations of strains with enhanced tolerance to TDA. No approach (single exposures to TDA extract administered via different methods, screening of a transposon library for resistant...

  2. Frontal and parietal cortical interactions with distributed visual representations during selective attention and action selection.

    Science.gov (United States)

    Nelissen, Natalie; Stokes, Mark; Nobre, Anna C; Rushworth, Matthew F S

    2013-10-16

    Using multivoxel pattern analysis (MVPA), we studied how distributed visual representations in human occipitotemporal cortex are modulated by attention and link their modulation to concurrent activity in frontal and parietal cortex. We detected similar occipitotemporal patterns during a simple visuoperceptual task and an attention-to-working-memory task in which one or two stimuli were cued before being presented among other pictures. Pattern strength varied from highest to lowest when the stimulus was the exclusive focus of attention, a conjoint focus, and when it was potentially distracting. Although qualitatively similar effects were seen inside regions relatively specialized for the stimulus category and outside, the former were quantitatively stronger. By regressing occipitotemporal pattern strength against activity elsewhere in the brain, we identified frontal and parietal areas exerting top-down control over, or reading information out from, distributed patterns in occipitotemporal cortex. Their interactions with patterns inside regions relatively specialized for that stimulus category were higher than those with patterns outside those regions and varied in strength as a function of the attentional condition. One area, the frontal operculum, was distinguished by selectively interacting with occipitotemporal patterns only when they were the focus of attention. There was no evidence that any frontal or parietal area actively inhibited occipitotemporal representations even when they should be ignored and were suppressed. Using MVPA to decode information within these frontal and parietal areas showed that they contained information about attentional context and/or readout information from occipitotemporal cortex to guide behavior but that frontal regions lacked information about category identity.

  3. Frontal and Parietal Cortical Interactions with Distributed Visual Representations during Selective Attention and Action Selection

    Science.gov (United States)

    Stokes, Mark; Nobre, Anna C.; Rushworth, Matthew F. S.

    2013-01-01

    Using multivoxel pattern analysis (MVPA), we studied how distributed visual representations in human occipitotemporal cortex are modulated by attention and link their modulation to concurrent activity in frontal and parietal cortex. We detected similar occipitotemporal patterns during a simple visuoperceptual task and an attention-to-working-memory task in which one or two stimuli were cued before being presented among other pictures. Pattern strength varied from highest to lowest when the stimulus was the exclusive focus of attention, a conjoint focus, and when it was potentially distracting. Although qualitatively similar effects were seen inside regions relatively specialized for the stimulus category and outside, the former were quantitatively stronger. By regressing occipitotemporal pattern strength against activity elsewhere in the brain, we identified frontal and parietal areas exerting top-down control over, or reading information out from, distributed patterns in occipitotemporal cortex. Their interactions with patterns inside regions relatively specialized for that stimulus category were higher than those with patterns outside those regions and varied in strength as a function of the attentional condition. One area, the frontal operculum, was distinguished by selectively interacting with occipitotemporal patterns only when they were the focus of attention. There was no evidence that any frontal or parietal area actively inhibited occipitotemporal representations even when they should be ignored and were suppressed. Using MVPA to decode information within these frontal and parietal areas showed that they contained information about attentional context and/or readout information from occipitotemporal cortex to guide behavior but that frontal regions lacked information about category identity. PMID:24133250

  4. Nuclear facility decommissioning and site remedial actions: A selected bibliography, Vol. 18. Part 2. Indexes

    International Nuclear Information System (INIS)

    1997-09-01

    This bibliography contains 3638 citations with abstracts of documents relevant to environmental restoration, nuclear facility decontamination and decommissioning (D ampersand D), uranium mill tailings management, and site remedial actions. This report is the eighteenth in a series of bibliographies prepared annually for the U.S. Department of Energy (DOE) Office of Environmental Restoration. Citations to foreign and domestic literature of all types - technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions - have been included in Part 1 of the report. The bibliography contains scientific, technical, financial, and regulatory information that pertains to DOE environmental restoration programs. The citations are separated by topic into 16 sections, including (1) DOE Environmental Restoration Program; (2) DOE D ampersand D Program; (3) Nuclear Facilities Decommissioning; (4) DOE Formerly Utilized Sites Remedial Action Programs; (5) NORM-Contaminated Site Restoration; (6) DOE Uranium Mill Tailings Remedial Action Project; (7) Uranium Mill Tailings Management; (8) DOE Site-Wide Remedial Actions; (9) DOE Onsite Remedial Action Projects; (10) Contaminated Site Remedial Actions; (11) DOE Underground Storage Tank Remediation; (12) DOE Technology Development, Demonstration, and Evaluations; (13) Soil Remediation; (14) Groundwater Remediation; (15) Environmental Measurements, Analysis, and Decision-Making; and (16) Environmental Management Issues. Within the 16 sections, the citations are sorted by geographic location. If a geographic location is not specified, the citations are sorted according to the document title. In Part 2 of the report, indexes are provided for author, author affiliation, selected title phrase, selected title word, publication description, geographic location, and keyword

  5. Nuclear facility decommissioning and site remedial actions: A selected bibliography, Vol. 18. Part 2. Indexes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    This bibliography contains 3638 citations with abstracts of documents relevant to environmental restoration, nuclear facility decontamination and decommissioning (D&D), uranium mill tailings management, and site remedial actions. This report is the eighteenth in a series of bibliographies prepared annually for the U.S. Department of Energy (DOE) Office of Environmental Restoration. Citations to foreign and domestic literature of all types - technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions - have been included in Part 1 of the report. The bibliography contains scientific, technical, financial, and regulatory information that pertains to DOE environmental restoration programs. The citations are separated by topic into 16 sections, including (1) DOE Environmental Restoration Program; (2) DOE D&D Program; (3) Nuclear Facilities Decommissioning; (4) DOE Formerly Utilized Sites Remedial Action Programs; (5) NORM-Contaminated Site Restoration; (6) DOE Uranium Mill Tailings Remedial Action Project; (7) Uranium Mill Tailings Management; (8) DOE Site-Wide Remedial Actions; (9) DOE Onsite Remedial Action Projects; (10) Contaminated Site Remedial Actions; (11) DOE Underground Storage Tank Remediation; (12) DOE Technology Development, Demonstration, and Evaluations; (13) Soil Remediation; (14) Groundwater Remediation; (15) Environmental Measurements, Analysis, and Decision-Making; and (16) Environmental Management Issues. Within the 16 sections, the citations are sorted by geographic location. If a geographic location is not specified, the citations are sorted according to the document title. In Part 2 of the report, indexes are provided for author, author affiliation, selected title phrase, selected title word, publication description, geographic location, and keyword.

  6. Code-specific learning rules improve action selection by populations of spiking neurons.

    Science.gov (United States)

    Friedrich, Johannes; Urbanczik, Robert; Senn, Walter

    2014-08-01

    Population coding is widely regarded as a key mechanism for achieving reliable behavioral decisions. We previously introduced reinforcement learning for population-based decision making by spiking neurons. Here we generalize population reinforcement learning to spike-based plasticity rules that take account of the postsynaptic neural code. We consider spike/no-spike, spike count and spike latency codes. The multi-valued and continuous-valued features in the postsynaptic code allow for a generalization of binary decision making to multi-valued decision making and continuous-valued action selection. We show that code-specific learning rules speed up learning both for the discrete classification and the continuous regression tasks. The suggested learning rules also speed up with increasing population size as opposed to standard reinforcement learning rules. Continuous action selection is further shown to explain realistic learning speeds in the Morris water maze. Finally, we introduce the concept of action perturbation as opposed to the classical weight- or node-perturbation as an exploration mechanism underlying reinforcement learning. Exploration in the action space greatly increases the speed of learning as compared to exploration in the neuron or weight space.

  7. Interim action record of decision remedial alternative selection: TNX area groundwater operable unit

    International Nuclear Information System (INIS)

    Palmer, E.R.

    1994-10-01

    This document presents the selected interim remedial action for the TNX Area Groundwater Operable Unit at the Savannah River Site (SRS), which was developed in accordance with CERCLA of 1980, as amended by the Superfund Amendments and Reauthorization Act (SARA) of 1986, and to the extent practicable, the National Oil and Hazardous Substances Pollution contingency Plan (NCP). This decision is based on the Administrative Record File for this specific CERCLA unit

  8. Cortical drive of low-frequency oscillations in the human nucleus accumbens during action selection.

    Science.gov (United States)

    Stenner, Max-Philipp; Litvak, Vladimir; Rutledge, Robb B; Zaehle, Tino; Schmitt, Friedhelm C; Voges, Jürgen; Heinze, Hans-Jochen; Dolan, Raymond J

    2015-07-01

    The nucleus accumbens is thought to contribute to action selection by integrating behaviorally relevant information from multiple regions, including prefrontal cortex. Studies in rodents suggest that information flow to the nucleus accumbens may be regulated via task-dependent oscillatory coupling between regions. During instrumental behavior, local field potentials (LFP) in the rat nucleus accumbens and prefrontal cortex are coupled at delta frequencies (Gruber AJ, Hussain RJ, O'Donnell P. PLoS One 4: e5062, 2009), possibly mediating suppression of afferent input from other areas and thereby supporting cortical control (Calhoon GG, O'Donnell P. Neuron 78: 181-190, 2013). In this report, we demonstrate low-frequency cortico-accumbens coupling in humans, both at rest and during a decision-making task. We recorded LFP from the nucleus accumbens in six epilepsy patients who underwent implantation of deep brain stimulation electrodes. All patients showed significant coherence and phase-synchronization between LFP and surface EEG at delta and low theta frequencies. Although the direction of this coupling as indexed by Granger causality varied between subjects in the resting-state data, all patients showed a cortical drive of the nucleus accumbens during action selection in a decision-making task. In three patients this was accompanied by a significant coherence increase over baseline. Our results suggest that low-frequency cortico-accumbens coupling represents a highly conserved regulatory mechanism for action selection. Copyright © 2015 the American Physiological Society.

  9. Action video games and improved attentional control: Disentangling selection- and response-based processes.

    Science.gov (United States)

    Chisholm, Joseph D; Kingstone, Alan

    2015-10-01

    Research has demonstrated that experience with action video games is associated with improvements in a host of cognitive tasks. Evidence from paradigms that assess aspects of attention has suggested that action video game players (AVGPs) possess greater control over the allocation of attentional resources than do non-video-game players (NVGPs). Using a compound search task that teased apart selection- and response-based processes (Duncan, 1985), we required participants to perform an oculomotor capture task in which they made saccades to a uniquely colored target (selection-based process) and then produced a manual directional response based on information within the target (response-based process). We replicated the finding that AVGPs are less susceptible to attentional distraction and, critically, revealed that AVGPs outperform NVGPs on both selection-based and response-based processes. These results not only are consistent with the improved-attentional-control account of AVGP benefits, but they suggest that the benefit of action video game playing extends across the full breadth of attention-mediated stimulus-response processes that impact human performance.

  10. Understanding the antimicrobial activity of selected disinfectants against methicillin-resistant Staphylococcus aureus (MRSA.

    Directory of Open Access Journals (Sweden)

    Ebrahim Aboualizadeh

    Full Text Available Disinfectants and biocidal products have been widely used to combat Methicillin-resistant Staphylococcus aureus (MRSA infections in homes and healthcare environments. Although disruption of cytoplasmic membrane integrity has been documented as the main bactericidal effect of biocides, little is known about the biochemical alterations induced by these chemical agents. In this study, we used Fourier transform infrared (FT-IR spectroscopy and chemometric tools as an alternative non-destructive technique to determine the bactericidal effects of commonly used disinfectants against MRSA USA-300. FTIR spectroscopy permits a detailed characterization of bacterial reactivity, allowing an understanding of the fundamental mechanism of action involved in the interaction between bacteria and disinfectants. The disinfectants studied were ethanol 70% (N = 5, isopropanol (N = 5, sodium hypochlorite (N = 5, triclosan (N = 5 and triclocarban (N = 5. Results showed less than 5% colony forming units growth of MRSA treated with triclocarban and no growth in the other groups. Nearly 70,000 mid-infrared spectra from the five treatments and the two control (untreated; N = 4 groups of MRSA (bacteria grown in TSB and incubated at 37°C (Control I / at ambient temperature (Control II, for 24h were pre-processed and analyzed using principal component analysis followed by linear discriminant analysis (PCA-LDA. Clustering of strains of MRSA belonging to five treatments and the discrimination between each treatment and two control groups in MRSA (untreated were investigated. PCA-LDA discriminatory frequencies suggested that ethanol-treated spectra are the most similar to isopropanol-treated spectra biochemically. Also reported here are the biochemical alterations in the structure of proteins, lipid membranes, and phosphate groups of MRSA produced by sodium hypochlorite, triclosan, and triclocarban treatments. These findings provide mechanistic information involved in the

  11. Understanding the antimicrobial activity of selected disinfectants against methicillin-resistant Staphylococcus aureus (MRSA).

    Science.gov (United States)

    Aboualizadeh, Ebrahim; Bumah, Violet V; Masson-Meyers, Daniela S; Eells, Janis T; Hirschmugl, Carol J; Enwemeka, Chukuka S

    2017-01-01

    Disinfectants and biocidal products have been widely used to combat Methicillin-resistant Staphylococcus aureus (MRSA) infections in homes and healthcare environments. Although disruption of cytoplasmic membrane integrity has been documented as the main bactericidal effect of biocides, little is known about the biochemical alterations induced by these chemical agents. In this study, we used Fourier transform infrared (FT-IR) spectroscopy and chemometric tools as an alternative non-destructive technique to determine the bactericidal effects of commonly used disinfectants against MRSA USA-300. FTIR spectroscopy permits a detailed characterization of bacterial reactivity, allowing an understanding of the fundamental mechanism of action involved in the interaction between bacteria and disinfectants. The disinfectants studied were ethanol 70% (N = 5), isopropanol (N = 5), sodium hypochlorite (N = 5), triclosan (N = 5) and triclocarban (N = 5). Results showed less than 5% colony forming units growth of MRSA treated with triclocarban and no growth in the other groups. Nearly 70,000 mid-infrared spectra from the five treatments and the two control (untreated; N = 4) groups of MRSA (bacteria grown in TSB and incubated at 37°C (Control I) / at ambient temperature (Control II), for 24h) were pre-processed and analyzed using principal component analysis followed by linear discriminant analysis (PCA-LDA). Clustering of strains of MRSA belonging to five treatments and the discrimination between each treatment and two control groups in MRSA (untreated) were investigated. PCA-LDA discriminatory frequencies suggested that ethanol-treated spectra are the most similar to isopropanol-treated spectra biochemically. Also reported here are the biochemical alterations in the structure of proteins, lipid membranes, and phosphate groups of MRSA produced by sodium hypochlorite, triclosan, and triclocarban treatments. These findings provide mechanistic information involved in the interaction

  12. Antimicrobial actions of the human epididymis 2 (HE2 protein isoforms, HE2alpha, HE2beta1 and HE2beta2

    Directory of Open Access Journals (Sweden)

    French Frank S

    2004-08-01

    Full Text Available Abstract Background The HE2 gene encodes a group of isoforms with similarities to the antimicrobial beta-defensins. We demonstrated earlier that the antimicrobial activity of HE2 proteins and peptides is salt resistant and structure dependent and involves permeabilization of bacterial membranes. In this study, we further characterize the antimicrobial properties of HE2 peptides in terms of the structural changes induced in E. coli and the inhibition of macromolecular synthesis. Methods E. coli treated with 50 micro g/ml of HE2alpha, HE2beta1 or HE2beta2 peptides for 30 and 60 min were visualized using transmission and scanning electron microscopy to investigate the impact of these peptides on bacterial internal and external structure. The effects of HE2alpha, HE2beta1 and HE2beta2 on E. coli macromolecular synthesis was assayed by incubating the bacteria with 2, 10 and 25 micro g/ml of the individual peptides for 0–60 min and measuring the incorporation of the radioactive precursors [methyl-3H]thymidine, [5-3H]uridine and L-[4,5-3H(N]leucine into DNA, RNA and protein. Statistical analyses using Student's t-test were performed using Sigma Plot software. Values shown are Mean ± S.D. Results E. coli treated with HE2alpha, HE2beta1 and HE2beta2 peptides as visualized by transmission electron microscopy showed extensive damage characterized by membrane blebbing, thickening of the membrane, highly granulated cytoplasm and appearance of vacuoles in contrast to the smooth and continuous membrane structure of the untreated bacteria. Similarly, bacteria observed by scanning electron microscopy after treating with HE2alpha, HE2beta1 or HE2beta2 peptides exhibited membrane blebbing and wrinkling, leakage of cellular contents, especially at the dividing septa, and external accumulation of fibrous materials. In addition, HE2alpha, HE2beta1 and HE2beta2 peptides inhibited E. coli DNA, RNA and protein synthesis. Conclusions The morphological changes observed

  13. Antimicrobial resistance challenged with metal-based antimicrobial macromolecules.

    Science.gov (United States)

    Abd-El-Aziz, Alaa S; Agatemor, Christian; Etkin, Nola

    2017-02-01

    Antimicrobial resistance threatens the achievements of science and medicine, as it deactivates conventional antimicrobial therapeutics. Scientists respond to the threat by developing new antimicrobial platforms to prevent and treat infections from these resistant strains. Metal-based antimicrobial macromolecules are emerging as an alternative to conventional platforms because they combine multiple mechanisms of action into one platform due to the distinctive properties of metals. For example, metals interact with intracellular proteins and enzymes, and catalyse various intracellular processes. The macromolecular architecture offers a means to enhance antimicrobial activity since several antimicrobial moieties can be conjugated to the scaffold. Further, these macromolecules can be fabricated into antimicrobial materials for contact-killing medical implants, fabrics, and devices. As volatilization or leaching out of the antimicrobial moieties from the macromolecular scaffold is reduced, these medical implants, fabrics, and devices can retain their antimicrobial activity over an extended period. Recent advances demonstrate the potential of metal-based antimicrobial macromolecules as effective platforms that prevent and treat infections from resistant strains. In this review these advances are thoroughly discussed within the context of examples of metal-based antimicrobial macromolecules, their mechanisms of action and biocompatibility. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Anti-microbial principles of selected remedial plants from Southern India.

    Science.gov (United States)

    Tirupathi, Rao G; Suresh, Babu K; Ujwal, Kumar J; Sujana, P; Raoa, A Veerabhadr; Sreedhar, A S

    2011-08-01

    To examine the anti-bacterial activity of leaf extracts of Morus alba L. (Moraceae) and Piper betel L. (Piperaceae), and seed extracts of Bombax ceiba L. (Borabacaceae). We have partially purified plant extracts by solvent extraction method, and evaluated the effect of individual fractions on bacterial growth using Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) bacterial strains. Compared with Morus and Bombax fractions, Piper fractions showed significant growth inhibition on all the three types of bacteria studied. The EtOAc-hexane fractions of Piper leaves exhibited significant anti-bacterial activity with minimum inhibitory concentrations (MIC) of 50 µg/mL culture against both gram-positive and gram-negative bacteria. The EtOAc-fractions I, II, and IV inhibited bacterial colony formation on soft agar in addition to growth inhibition. A combination treatment of piper fractions with ampicillin resulted in significant growth inhibition in E. coli and P. aeruginosa, and combination with anticancer drug geldanamycin (2µg/mL) showed selective growth inhibition against P. aeruginosa and S. aureus. Three major compounds, i.e., eugenol, 3-hexene-ol and stigmasterol, were primarily identified from Piper betel leaf extractions. Among the individual compounds, eugenol treatment showed improved growth inhibition compared with stigmasterol and 3-hexene-ol. We are reporting potential anti-bacterial compounds from Piper betel against both gram-positive and gram-negative bacteria either alone or in combination with drug treatment.

  15. Searching and selecting online information: analysis of the strategic actions of the university students

    Directory of Open Access Journals (Sweden)

    María José Hernández Serrano

    2013-08-01

    Full Text Available 0 0 1 113 622 USAL 5 1 734 14.0 Normal 0 21 false false false ES JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:Calibri; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-ansi-language:ES; mso-fareast-language:EN-US;} As complex and dynamic activity, the searching and selection of online information needs a strategic performance in order to achieve effective and meaningful results and processes. The aim of this paper is to analyze whether university students perceive a need to be strategic, for what actions, what times, and what are their predispositions towards the strategic actions in the Internet information searching and selection process. Results showed differences between students by course, those in their final courses, who have also received training, showed better predisposition to strategic actions. Two factors that explain the university students’ predispositions were found, in terms of basic actions and complementary actions.

  16. Attentional selection in visual perception, memory and action: a quest for cross-domain integration

    Science.gov (United States)

    Schneider, Werner X.; Einhäuser, Wolfgang; Horstmann, Gernot

    2013-01-01

    For decades, the cognitive and neural sciences have benefitted greatly from a separation of mind and brain into distinct functional domains. The tremendous success of this approach notwithstanding, it is self-evident that such a view is incomplete. Goal-directed behaviour of an organism requires the joint functioning of perception, memory and sensorimotor control. A prime candidate for achieving integration across these functional domains are attentional processes. Consequently, this Theme Issue brings together studies of attentional selection from many fields, both experimental and theoretical, that are united in their quest to find overreaching integrative principles of attention between perception, memory and action. In all domains, attention is understood as combination of competition and priority control (‘bias’), with the task as a decisive driving factor to ensure coherent goal-directed behaviour and cognition. Using vision as the predominant model system for attentional selection, many studies of this Theme Issue focus special emphasis on eye movements as a selection process that is both a fundamental action and serves a key function in perception. The Theme Issue spans a wide range of methods, from measuring human behaviour in the real word to recordings of single neurons in the non-human primate brain. We firmly believe that combining such a breadth in approaches is necessary not only for attentional selection, but also to take the next decisive step in all of the cognitive and neural sciences: to understand cognition and behaviour beyond isolated domains. PMID:24018715

  17. Attentional selection in visual perception, memory and action: a quest for cross-domain integration.

    Science.gov (United States)

    Schneider, Werner X; Einhäuser, Wolfgang; Horstmann, Gernot

    2013-10-19

    For decades, the cognitive and neural sciences have benefitted greatly from a separation of mind and brain into distinct functional domains. The tremendous success of this approach notwithstanding, it is self-evident that such a view is incomplete. Goal-directed behaviour of an organism requires the joint functioning of perception, memory and sensorimotor control. A prime candidate for achieving integration across these functional domains are attentional processes. Consequently, this Theme Issue brings together studies of attentional selection from many fields, both experimental and theoretical, that are united in their quest to find overreaching integrative principles of attention between perception, memory and action. In all domains, attention is understood as combination of competition and priority control ('bias'), with the task as a decisive driving factor to ensure coherent goal-directed behaviour and cognition. Using vision as the predominant model system for attentional selection, many studies of this Theme Issue focus special emphasis on eye movements as a selection process that is both a fundamental action and serves a key function in perception. The Theme Issue spans a wide range of methods, from measuring human behaviour in the real word to recordings of single neurons in the non-human primate brain. We firmly believe that combining such a breadth in approaches is necessary not only for attentional selection, but also to take the next decisive step in all of the cognitive and neural sciences: to understand cognition and behaviour beyond isolated domains.

  18. Antimicrobial action of chlorhexidine digluconate in self-ligating and conventional metal brackets infected with Streptococcus mutans biofilm

    Directory of Open Access Journals (Sweden)

    Dias AP

    2018-04-01

    Full Text Available Ana Paula Dias, Marco Aurélio Benini Paschoal, Rafael Soares Diniz, Lucas Meneses Lage, Letícia Machado Gonçalves Department of Dentistry, CEUMA University, São Luis, Maranhão, Brazil Objectives: The objectives of this study were to assess the adherence of Streptococcus mutans biofilms grown over conventional ligature (CL or self-ligating (SL metal brackets and their bacterial viability after 0.12% chlorhexidine (CHX digluconate treatment. Materials and methods: The sample consisted of 48 metallic orthodontic brackets divided randomly into two groups: CL (n=24 and SL brackets (n=24. S. mutans biofilms were grown over the bracket surface (96 h and treated with CHX (positive control or 0.9% phosphate-buffered saline (PBS (negative control for 1 min each. Quantitative analysis was assessed by colony-forming units, and fluorescence microscopy was performed aiming to illustrate the outcomes. The tests were done in triplicate at three different times (n=9. Data were analyzed using ANOVA and Tukey test (P<0.05. Results: There were significant differences in brackets’ biofilm formation, being CL largely colonized compared with SL, which was observed by colony-forming unit counting (P<0.05 and microcopy images. Significant reduction in the viability of S. mutans was found in both brackets treated with CHX compared to PBS (P<0.05. Conclusion: The antimicrobial activities of CHX were similar for CL and SL brackets (P>0.05. In conclusion, a lower colonization was achieved in SL brackets and S. mutans biofilms were susceptible to CHX treatment to both studied brackets. Keywords: biofilm, chlorhexidine, orthodontic brackets, Streptococcus mutans

  19. Alternative Antimicrobial Approach: Nano-Antimicrobial Materials

    Directory of Open Access Journals (Sweden)

    Nurit Beyth

    2015-01-01

    Full Text Available Despite numerous existing potent antibiotics and other antimicrobial means, bacterial infections are still a major cause of morbidity and mortality. Moreover, the need to develop additional bactericidal means has significantly increased due to the growing concern regarding multidrug-resistant bacterial strains and biofilm associated infections. Consequently, attention has been especially devoted to new and emerging nanoparticle-based materials in the field of antimicrobial chemotherapy. The present review discusses the activities of nanoparticles as an antimicrobial means, their mode of action, nanoparticle effect on drug-resistant bacteria, and the risks attendant on their use as antibacterial agents. Factors contributing to nanoparticle performance in the clinical setting, their unique properties, and mechanism of action as antibacterial agents are discussed in detail.

  20. Selective effects of potassium elevations on glutamate signaling and action potential conduction in hippocampus.

    Science.gov (United States)

    Meeks, Julian P; Mennerick, Steven

    2004-01-07

    High-frequency synaptic transmission is depressed by moderate rises in the extracellular potassium concentration ([K+]o). Previous reports have indicated that depression of action potential signaling may underlie the synaptic depression. Here, we investigated the specific contribution of K+-induced action potential changes to synaptic depression. We found that glutamatergic transmission in the hippocampal area CA1 was significantly depressed by 8-10 mM [K+]o, but that GABAergic transmission remained intact. Riluzole, a drug that slows recovery from inactivation of voltage-gated sodium channels (NaChs), interacts with subthreshold [K+]o to depress afferent volleys and EPSCs strongly. Thus, elevated [K+]o likely depresses synapses by slowing NaCh recovery from inactivation. It is unclear from previous studies whether [K+]o-induced action potential depression is caused by changes in initiation, reliability, or waveform. We investigated these possibilities explicitly. [K+]o-induced afferent volley depression was independent of stimulus strength, suggesting that changes in action potential initiation do not explain [K+]o-induced depression. Measurements of action potentials from single axons revealed that 8 mM [K+]o increased conduction failures in a subpopulation of fibers and depressed action potential amplitude in all fibers. Together, these changes quantitatively account for the afferent volley depression. We estimate that conduction failure explains more than half of the synaptic depression observed at 8 mM [K+]o, with the remaining depression likely explained by waveform changes. These mechanisms of selective sensitivity of glutamate release to [K+]o accumulation represent a unique neuromodulatory mechanism and a brake on runaway excitation.

  1. Mechanism of action of the tri-hybrid antimicrobial peptide LHP7 from lactoferricin, HP and plectasin on Staphylococcus aureus.

    Science.gov (United States)

    Xi, Di; Wang, Xiumin; Teng, Da; Mao, Ruoyu

    2014-10-01

    The tri-hybrid peptide-LHP7 has the potent activity against Gram-positive and Gram-negative as well as fungi, but its mechanism of action has remained elusive. The effluences of LHP7 on the Staphylococcus aureus cell membrane and targets of intracellular action were investigated. LHP7 exhibited an inhibitory effect on the S. aureus growth, similar to those achieved by plectasin, vancomycin and gramicidin. The membrane integrity studies confirmed that LHP7 disrupted the cell membrane, indicating a membrane permeabilizing killing action. A marginal decline in the intensity fluorescence indicated no significant depolarization of the membrane potential following LHP7 treatment. Furthermore, electron microscopy showed that cell shrinkage, cell wall thickening, cellular content leakage, and cell disruption were observed in the cells treated with LHP7. A gel retardation assay showed that LHP7 bound to the genomic DNA of S. aureus or plasmid DNA at a mass ratio of 2.5–10 (peptide/DNA). Circular dichroism indicated that LHP7 inserted into the groove of DNA. The cell cycle analysis showed that after the treatment with LHP7 for 30 and 60 min, the proportion of cells in I-phase increased from 8.71 to 12.09 % and from 8.71 to 15.68 %, indicating that LHP7 induced arrest of cells in the I-phase. These results would conduce to elucidate its underlying antibacterial mechanism.

  2. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... proliferates among bacteria. Over time, the use of antimicrobial drugs will result in the development of resistant strains ... bacteria, complicating clinician's efforts to select the appropriate ... and human medicine to preserve the effectiveness of these drugs. One ...

  3. Dissociating action-effect activation and effect-based response selection.

    Science.gov (United States)

    Schwarz, Katharina A; Pfister, Roland; Wirth, Robert; Kunde, Wilfried

    2018-05-25

    Anticipated action effects have been shown to govern action selection and initiation, as described in ideomotor theory, and they have also been demonstrated to determine crosstalk between different tasks in multitasking studies. Such effect-based crosstalk was observed not only in a forward manner (with a first task influencing performance in a following second task) but also in a backward manner (the second task influencing the preceding first task), suggesting that action effect codes can become activated prior to a capacity-limited processing stage often denoted as response selection. The process of effect-based response production, by contrast, has been proposed to be capacity-limited. These observations jointly suggest that effect code activation can occur independently of effect-based response production, though this theoretical implication has not been tested directly at present. We tested this hypothesis by employing a dual-task set-up in which we manipulated the ease of effect-based response production (via response-effect compatibility) in an experimental design that allows for observing forward and backward crosstalk. We observed robust crosstalk effects and response-effect compatibility effects alike, but no interaction between both effects. These results indicate that effect activation can occur in parallel for several tasks, independently of effect-based response production, which is confined to one task at a time. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Nuclear facility decommissioning and site remedial actions. Volume 1. A selected bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Faust, R.A.; Fore, C.S.; Knox, N.P.

    1980-09-01

    This bibliography of 633 references represents the first in a series to be produced by the Remedial Actions Program Information Center (RAPIC) containing scientific, technical, economic, and regulatory information concerning the decommissioning of nuclear facilities. Major chapters selected for this bibliography are Facility Decommissioning, Uranium Mill Tailings Cleanup, Contaminated Site Restoration, and Criteria and Standards. The references within each chapter are arranged alphabetically by leading author, corporate affiliation, or title of the document. When the author is not given, the corporate affiliation appears first. If these two levels of authorship are not given, the title of the document is used as the identifying level. Indexes are provided for (1) author(s), (2) keywords, (3) title, (4) technology development, and (5) publication description. An appendix of 123 entries lists recently acquired references relevant to decommissioning of nuclear facilities. These references are also arranged according to one of the four subject categories and followed by author, title, and publication description indexes. The bibliography was compiled from a specialized data base established and maintained by RAPIC to provide information support for the Department of Energy's Remedial Actions Program, under the cosponsorship of its three major components: Surplus Facilities Management Program, Uranium Mill Tailings Remedial Actions Program, and Formerly Utilized Sites Remedial Actions Program. RAPIC is part of the Ecological Sciences Information Center within the Information Center Complex at Oak Ridge National Laboratory.

  5. Nuclear facility decommissioning and site remedial actions. Volume 1. A selected bibliography

    International Nuclear Information System (INIS)

    Faust, R.A.; Fore, C.S.; Knox, N.P.

    1980-09-01

    This bibliography of 633 references represents the first in a series to be produced by the Remedial Actions Program Information Center (RAPIC) containing scientific, technical, economic, and regulatory information concerning the decommissioning of nuclear facilities. Major chapters selected for this bibliography are Facility Decommissioning, Uranium Mill Tailings Cleanup, Contaminated Site Restoration, and Criteria and Standards. The references within each chapter are arranged alphabetically by leading author, corporate affiliation, or title of the document. When the author is not given, the corporate affiliation appears first. If these two levels of authorship are not given, the title of the document is used as the identifying level. Indexes are provided for (1) author(s), (2) keywords, (3) title, (4) technology development, and (5) publication description. An appendix of 123 entries lists recently acquired references relevant to decommissioning of nuclear facilities. These references are also arranged according to one of the four subject categories and followed by author, title, and publication description indexes. The bibliography was compiled from a specialized data base established and maintained by RAPIC to provide information support for the Department of Energy's Remedial Actions Program, under the cosponsorship of its three major components: Surplus Facilities Management Program, Uranium Mill Tailings Remedial Actions Program, and Formerly Utilized Sites Remedial Actions Program. RAPIC is part of the Ecological Sciences Information Center within the Information Center Complex at Oak Ridge National Laboratory

  6. Antimicrobial Peptides in 2014

    Directory of Open Access Journals (Sweden)

    Guangshun Wang

    2015-03-01

    Full Text Available This article highlights new members, novel mechanisms of action, new functions, and interesting applications of antimicrobial peptides reported in 2014. As of December 2014, over 100 new peptides were registered into the Antimicrobial Peptide Database, increasing the total number of entries to 2493. Unique antimicrobial peptides have been identified from marine bacteria, fungi, and plants. Environmental conditions clearly influence peptide activity or function. Human α-defensin HD-6 is only antimicrobial under reduced conditions. The pH-dependent oligomerization of human cathelicidin LL-37 is linked to double-stranded RNA delivery to endosomes, where the acidic pH triggers the dissociation of the peptide aggregate to release its cargo. Proline-rich peptides, previously known to bind to heat shock proteins, are shown to inhibit protein synthesis. A model antimicrobial peptide is demonstrated to have multiple hits on bacteria, including surface protein delocalization. While cell surface modification to decrease cationic peptide binding is a recognized resistance mechanism for pathogenic bacteria, it is also used as a survival strategy for commensal bacteria. The year 2014 also witnessed continued efforts in exploiting potential applications of antimicrobial peptides. We highlight 3D structure-based design of peptide antimicrobials and vaccines, surface coating, delivery systems, and microbial detection devices involving antimicrobial peptides. The 2014 results also support that combination therapy is preferred over monotherapy in treating biofilms.

  7. Record of Decision Remedial Alternative Selection for the Gunsite 113 Access Road (631-24G) Operable Unit: Final Action

    International Nuclear Information System (INIS)

    Palmer, E.

    1997-01-01

    This decision document presents the selected remedial action for the Gunsite 113 Access Road Unit located at the Savannah River Site near Aiken, SC. The selected action was developed in accordance with CERCLA, as amended, and to the extent practicable, the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). The selected remedy satisfies both CERCLA and RCRA 3004(U) requirements. This decision is based ont he Administrative Record File for this specific RCRA/CERCLA Unit

  8. Differential Effects of Systemic Cholinergic Receptor Blockade on Pavlovian Incentive Motivation and Goal-Directed Action Selection

    Science.gov (United States)

    Ostlund, Sean B; Kosheleff, Alisa R; Maidment, Nigel T

    2014-01-01

    Reward-seeking actions can be guided by external cues that signal reward availability. For instance, when confronted with a stimulus that signals sugar, rats will prefer an action that produces sugar over a second action that produces grain pellets. Action selection is also sensitive to changes in the incentive value of potential rewards. Thus, rats that have been prefed a large meal of sucrose will prefer a grain-seeking action to a sucrose-seeking action. The current study investigated the dependence of these different aspects of action selection on cholinergic transmission. Hungry rats were given differential training with two unique stimulus-outcome (S1-O1 and S2-O2) and action-outcome (A1-O1 and A2-O2) contingencies during separate training phases. Rats were then given a series of Pavlovian-to-instrumental transfer tests, an assay of cue-triggered responding. Before each test, rats were injected with scopolamine (0, 0.03, or 0.1 mg/kg, intraperitoneally), a muscarinic receptor antagonist, or mecamylamine (0, 0.75, or 2.25 mg/kg, intraperitoneally), a nicotinic receptor antagonist. Although the reward-paired cues were capable of biasing action selection when rats were tested off-drug, both anticholinergic treatments were effective in disrupting this effect. During a subsequent round of outcome devaluation testing—used to assess the sensitivity of action selection to a change in reward value—we found no effect of either scopolamine or mecamylamine. These results reveal that cholinergic signaling at both muscarinic and nicotinic receptors mediates action selection based on Pavlovian reward expectations, but is not critical for flexibly selecting actions using current reward values. PMID:24370780

  9. In vitro assessment of antiproliferative action selectivity of dietary isothiocyanates for tumor versus normal human cells

    Directory of Open Access Journals (Sweden)

    Konić-Ristić Aleksandra

    2016-01-01

    Full Text Available Background/Aim. Numerous epidemiological studies have shown beneficial effects of cruciferous vegetables consumption in cancer chemoprevention. Biologically active compounds of different Brassicaceae species with antitumor potential are isothiocyanates, present in the form of their precursors - glucosinolates. The aim of this study was to determine the selectivity of antiproliferative action of dietary isothiocyanates for malignant versus normal cells. Methods. Antiproliferative activity of three isothiocyanates abundant in human diet: sulforaphane, benzyl isothiocyanate (BITC and phenylethyl isothiocyanate, on human cervix carcinoma cell line - HeLa, melanoma cell line - Fem-x, and colon cancer cell line - LS 174, and on peripheral blood mononuclear cells (PBMC, with or without mitogen, were determined by MTT colorimetric assay 72 h after their continuous action. Results. All investigated isothiocyanates inhibited the proliferation of HeLa, Fem-x and LS 174 cells. On all cell lines treated, BITC was the most potent inhibitor of cell proliferation with half-maximum inhibitory concentration (IC50 values of 5.04 mmoL m-3 on HeLa cells, 2.76 mmol m-3 on Fem-x, and 14.30 mmol m-3 on LS 174 cells. Antiproliferative effects on human PBMC were with higher IC50 than on malignant cells. Indexes of selectivity, calculated as a ratio between IC50 values obtained on PBMC and malignant cells, were between 1.12 and 16.57, with the highest values obtained for the action of BITC on melanoma Fem-x cells. Conclusion. Based on its antiproliferative effects on malignant cells, as well as the selectivity of the action to malignant vs normal cells, benzyl isothiocyanate can be considered as a promising candidate in cancer chemoprevention. In general, the safety of investigated compounds, in addition to their antitumor potential, should be considered as an important criterion in cancer chemoprevention. Screening of selectivity is a plausible approach to the evaluation

  10. Steps Toward Innovative Childbirth Education: Selected Strategies From the Blueprint for Action

    Science.gov (United States)

    Jolivet, R. Rima; Corry, Maureen P.

    2010-01-01

    To mark the 50th anniversary of Lamaze International, Childbirth Connection celebrates landmark accomplishments in education for childbearing women and families, and takes stock of the changing educational needs and preferences of current childbearing families in looking toward the future. Childbirth Connection's multi-year, multi-stakeholder Transforming Maternity Care initiative resulted in two landmark reports: 2020 Vision for a High-Quality, High-Value Maternity Care System and Blueprint for Action: Steps Toward a High-Quality, High-Value Maternity Care System. Selected recommendations of greatest relevance to the field of childbirth education are discussed, and the new Transforming Maternity Care Partnership is introduced. PMID:21629389

  11. Selective attention and control of action: comparative psychology of an artificial, evolved agent and people.

    Science.gov (United States)

    Ward, Robert; Ward, Ronnie

    2008-10-01

    This study examined the selective attention abilities of a simple, artificial, evolved agent and considered implications of the agent's performance for theories of selective attention and action. The agent processed two targets in continuous time, catching one and then the other. This task required many cognitive operations, including prioritizing the first target (T1) over the second (T2); selectively focusing responses on T1, while preventing T2 from interfering with responses; creating a memory for the unselected T2 item, so that it could be efficiently processed later; and reallocating processing towards T2 after catching T1. The evolved agent demonstrated all these abilities. Analysis shows that the agent used reactive inhibition to selectively focus behavior. That is, the more salient T2, the more strongly responses towards T2 were inhibited and the slower the agent was to subsequently reallocate processing towards T2. Reactive inhibition was also suggested in two experiments with people, performing a virtually identical catch task. The presence of reactive inhibition in the simple agent and in people suggests that it is an important mechanism for selective processing.

  12. The determination of minimum inhibitory concentrations of selected antimicrobials for porcine Haemophilus parasuis isolates from the Czech Republic

    Directory of Open Access Journals (Sweden)

    Kateřina Nedbalcová

    2017-01-01

    Full Text Available Haemophilus parasuis isolates obtained from pigs in the Czech Republic were tested for their susceptibility to amoxicillin, penicillin, ceftiofur, enrofloxacin, tetracycline, and tulathromycin by determination of minimum inhibitory concentrations using the broth microdilution method. The H. parasuis isolates were mostly susceptible to majority of tested antimicrobials (amoxicillin 90%, penicillin 73.3%, enrofloxacin 83.3%, and tulathromycin 83.3%. All isolates were susceptible to ceftiofur. On the other hand, no isolate was susceptible to tetracycline, 30% of tested isolates were intermediately susceptible, and 70% were resistant. These findings indicate that tested antimicrobials with the exception of tetracycline should be the preferred option used for the treatment of infection caused by H. parasuis but due to the potential transmission of resistance from animals to humans, the use of ceftiofur is considered as a last resort option in antimicrobial treatment of animals.

  13. Redesigned Spider Peptide with Improved Antimicrobial and Anticancer Properties.

    Science.gov (United States)

    Troeira Henriques, Sónia; Lawrence, Nicole; Chaousis, Stephanie; Ravipati, Anjaneya S; Cheneval, Olivier; Benfield, Aurélie H; Elliott, Alysha G; Kavanagh, Angela Maria; Cooper, Matthew A; Chan, Lai Yue; Huang, Yen-Hua; Craik, David J

    2017-09-15

    Gomesin, a disulfide-rich antimicrobial peptide produced by the Brazilian spider Acanthoscurria gomesiana, has been shown to be potent against Gram-negative bacteria and to possess selective anticancer properties against melanoma cells. In a recent study, a backbone cyclized analogue of gomesin was shown to be as active but more stable than its native form. In the current study, we were interested in improving the antimicrobial properties of the cyclic gomesin, understanding its selectivity toward melanoma cells and elucidating its antimicrobial and anticancer mode of action. Rationally designed analogues of cyclic gomesin were examined for their antimicrobial potency, selectivity toward cancer cells, membrane-binding affinity, and ability to disrupt cell and model membranes. We improved the activity of cyclic gomesin by ∼10-fold against tested Gram-negative and Gram-positive bacteria without increasing toxicity to human red blood cells. In addition, we showed that gomesin and its analogues are more toxic toward melanoma and leukemia cells than toward red blood cells and act by selectively targeting and disrupting cancer cell membranes. Preference toward some cancer types is likely dependent on their different cell membrane properties. Our findings highlight the potential of peptides as antimicrobial and anticancer leads and the importance of selectively targeting cancer cell membranes for drug development.

  14. Mushroom body output neurons encode valence and guide memory-based action selection in Drosophila.

    Science.gov (United States)

    Aso, Yoshinori; Sitaraman, Divya; Ichinose, Toshiharu; Kaun, Karla R; Vogt, Katrin; Belliart-Guérin, Ghislain; Plaçais, Pierre-Yves; Robie, Alice A; Yamagata, Nobuhiro; Schnaitmann, Christopher; Rowell, William J; Johnston, Rebecca M; Ngo, Teri-T B; Chen, Nan; Korff, Wyatt; Nitabach, Michael N; Heberlein, Ulrike; Preat, Thomas; Branson, Kristin M; Tanimoto, Hiromu; Rubin, Gerald M

    2014-12-23

    Animals discriminate stimuli, learn their predictive value and use this knowledge to modify their behavior. In Drosophila, the mushroom body (MB) plays a key role in these processes. Sensory stimuli are sparsely represented by ∼2000 Kenyon cells, which converge onto 34 output neurons (MBONs) of 21 types. We studied the role of MBONs in several associative learning tasks and in sleep regulation, revealing the extent to which information flow is segregated into distinct channels and suggesting possible roles for the multi-layered MBON network. We also show that optogenetic activation of MBONs can, depending on cell type, induce repulsion or attraction in flies. The behavioral effects of MBON perturbation are combinatorial, suggesting that the MBON ensemble collectively represents valence. We propose that local, stimulus-specific dopaminergic modulation selectively alters the balance within the MBON network for those stimuli. Our results suggest that valence encoded by the MBON ensemble biases memory-based action selection.

  15. The Emergence of Selective Attention through Probabilistic Associations between Stimuli and Actions.

    Directory of Open Access Journals (Sweden)

    Luca Simione

    Full Text Available In this paper we show how a multilayer neural network trained to master a context-dependent task in which the action co-varies with a certain stimulus in a first context and with a second stimulus in an alternative context exhibits selective attention, i.e. filtering out of irrelevant information. This effect is rather robust and it is observed in several variations of the experiment in which the characteristics of the network as well as of the training procedure have been varied. Our result demonstrates how the filtering out of irrelevant information can originate spontaneously as a consequence of the regularities present in context-dependent training set and therefore does not necessarily depend on specific architectural constraints. The post-evaluation of the network in an instructed-delay experimental scenario shows how the behaviour of the network is consistent with the data collected in neuropsychological studies. The analysis of the network at the end of the training process indicates how selective attention originates as a result of the effects caused by relevant and irrelevant stimuli mediated by context-dependent and context-independent bidirectional associations between stimuli and actions that are extracted by the network during the learning.

  16. Direction-selective circuitry in rat retina develops independently of GABAergic, cholinergic and action potential activity.

    Directory of Open Access Journals (Sweden)

    Le Sun

    Full Text Available The ON-OFF direction selective ganglion cells (DSGCs in the mammalian retina code image motion by responding much more strongly to movement in one direction. They do so by receiving inhibitory inputs selectively from a particular sector of processes of the overlapping starburst amacrine cells, a type of retinal interneuron. The mechanisms of establishment and regulation of this selective connection are unknown. Here, we report that in the rat retina, the morphology, physiology of the ON-OFF DSGCs and the circuitry for coding motion directions develop normally with pharmacological blockade of GABAergic, cholinergic activity and/or action potentials for over two weeks from birth. With recent results demonstrating light independent formation of the retinal DS circuitry, our results strongly suggest the formation of the circuitry, i.e., the connections between the second and third order neurons in the visual system, can be genetically programmed, although emergence of direction selectivity in the visual cortex appears to require visual experience.

  17. Rational Action Selection in 1 1/2- to 3-Year-Olds Following an Extended Training Experience

    Science.gov (United States)

    Klossek, Ulrike M. H.; Dickinson, Anthony

    2012-01-01

    Previous studies failed to find evidence for rational action selection in children under 2 years of age. The current study investigated whether younger children required more training to encode the relevant causal relationships. Children between 1 1/2 and 3 years of age were trained over two sessions to perform actions on a touch-sensitive screen…

  18. Preparation, characterization, and the selective antimicrobial activity of N-alkylammonium 8-diethyleneglycol cobalt bis-dicarbollide derivatives

    Czech Academy of Sciences Publication Activity Database

    Kvasničková, E.; Masák, J.; Čejka, J.; Maťátková, O.; Šícha, Václav

    2017-01-01

    Roč. 827, JAN (2017), s. 23-31 ISSN 0022-328X R&D Projects: GA ČR(CZ) GA15-05677S Institutional support: RVO:61388980 Keywords : Alkylammonium * Antimicrobial * Metallacarboranes * Staphylococcus aureus * Oxonium ring opening * Trichosporon cutaneum Subject RIV: CA - Inorganic Chemistry OBOR OECD: Inorganic and nuclear chemistry Impact factor: 2.184, year: 2016

  19. Effect of different scenarios for selective dry-cow therapy on udder health, antimicrobial usage, and economics

    NARCIS (Netherlands)

    Scherpenzeel, C G M; den Uijl, I E M; van Schaik, G; Riekerink, R G M Olde; Hogeveen, H; Lam, T J G M

    2016-01-01

    The goal of dry-cow therapy (DCT) is to reduce the prevalence of intramammary infections (IMI) by eliminating existing IMI at drying off and preventing new IMI from occurring during the dry period. Due to public health concerns, however, preventive use of antimicrobials has become questionable. In

  20. Effect of different scenarios for selective dry-cow therapy on udder health, antimicrobial usage, and economics

    NARCIS (Netherlands)

    Scherpenzeel, C.G.M.; Uijl, den I.E.M.; Schaik, van G.; Riekerink, Olde R.G.M.; Hogeveen, H.; Lam, T.J.G.M.

    2016-01-01

    The goal of dry-cow therapy (DCT) is to reduce the prevalence of intramammary infections (IMI) by eliminating existing IMI at drying off and preventing new IMI from occurring during the dry period. Due to public health concerns, however, preventive use of antimicrobials has become questionable.

  1. Determination of antimicrobial resistance to extended-spectrum cephalosporin, quinolones, and vancomycin in selected human enteric pathogens from Prince Edward Island, Canada.

    Science.gov (United States)

    Awosile, Babafela; German, Gregory; Rodriguez-Lecompte, Juan Carlos; Saab, Matthew E; Heider, Luke C; McClure, J Trenton

    2018-04-05

    The aim of this study was to determine the frequency of fecal carriage of vancomycin-resistant Enterococcus spp. and Escherichia coli with reduced susceptibilities to extended-spectrum cephalosporins (ESCs) and quinolones in humans on Prince Edward Island, Canada. Convenience fecal samples from individuals on Prince Edward Island were screened phenotypically using selective culture and genotypically using multiplex polymerase chain reactions to detect E. coli and Enterococcus spp. resistant to critically important antimicrobials. Twenty-six (5.3%) of 489 individuals had E. coli with reduced susceptibility to ESCs. Twenty-five (96.2%) of the 26 isolates harbored bla TEM , 18 (69.2%) harbored bla CMY-2 , 16 (61.5%) harbored bla CTX-M groups, 2 (7.7%) harbored bla SHV genes. None of the ESC-resistant E. coli was positive for carbapenem resistance. Twenty-one (8.3%) of 253 individuals had E. coli isolates with reduced quinolone susceptibility. All 21 isolates were positive for at least 1 qnr gene, with 3 (14.3%) isolates positive for qnrB, 5 (23.8%) positive for qnrS, and 13 (61.9%) positive for both qnrB and qnrS genes. All the enterococci isolates were vancomycin-susceptible. Higher susceptibility to the critically important antimicrobials was found in this study. This study can serve as a baseline for future antimicrobial resistance surveillance within this region.

  2. EEG alpha activity reflects motor preparation rather than the mode of action selection

    Directory of Open Access Journals (Sweden)

    Marie-Pierre eDeiber

    2012-08-01

    Full Text Available Alpha-band activity (8-13 Hz is suppressed by sensory stimulation and movements, modulated by attention, working memory and mental tasks and may be sensitive to higher motor control functions. The aim of the present study was to examine alpha oscillatory activity during the preparation of simple left or right finger movements, contrasting the external and internal mode of action selection. Three preparation conditions were examined using a precueing paradigm with S1 as the preparatory and S2 as the imperative cue: Full, laterality instructed by S1; Free, laterality freely selected and None, laterality instructed by S2. Time-frequency analysis was performed in the alpha frequency range during the S1-S2 interval, and alpha motor-related amplitude asymmetries (MRAA were also calculated. The significant MRAA during the Full and Free conditions indicated effective external and internal motor response preparation. In the absence of specific motor preparation (None, a posterior alpha power decrease (event-related desynchronization, ERD dominated, reflecting the main engagement of attentional resources. In Full and Free motor preparation, posterior alpha ERD was accompanied by a midparietal alpha power increase (event-related synchronization, ERS, suggesting a concomitant inhibition of task-irrelevant visual activity. In both Full and Free motor preparation, analysis of alpha power according to MRAA amplitude revealed two types of functional activation patterns: 1 a motor alpha pattern, with predominantly midparietal alpha ERS and large MRAA corresponding to lateralized motor activation/visual inhibition and 2 an attentional alpha pattern, with dominating right posterior alpha ERD and small MRAA reflecting visuospatial attention. The present results suggest that alpha oscillatory patterns do not resolve the selection mode of action, but rather distinguish separate functional strategies of motor preparation. 

  3. Antimicrobial Resistance

    Science.gov (United States)

    ... least 10 countries (Australia, Austria, Canada, France, Japan, Norway, Slovenia, South Africa, Sweden and the United Kingdom ... plan Global report on surveillance Country situation analysis Policy to combat antimicrobial resistance More on antimicrobial resistance ...

  4. Antimicrobials Treatment

    Science.gov (United States)

    Drosinos, Eleftherios H.; Skandamis, Panagiotis N.; Mataragas, Marios

    The use of antimicrobials is a common practice for preservation of foods. Incorporation, in a food recipe, of chemical antimicrobials towards inhibition of spoilage and pathogenic micro-organisms results in the compositional modification of food. This treatment is nowadays undesirable for the consumer, who likes natural products. Scientific community reflecting consumers demand for natural antimicrobials has made efforts to investigate the possibility to use natural antimicrobials such us bacteriocins and essential oils of plant origin to inhibit microbial growth.

  5. Anti-Inflammatory Action of an Antimicrobial Model Peptide That Suppresses the TRIF-Dependent Signaling Pathway via Inhibition of Toll-Like Receptor 4 Endocytosis in Lipopolysaccharide-Stimulated Macrophages.

    Directory of Open Access Journals (Sweden)

    Do-Wan Shim

    Full Text Available Antimicrobial peptides (AMPs, also called host defense peptides, particularly those with amphipathic helical structures, are emerging as target molecules for therapeutic development due to their immunomodulatory properties. Although the antimicrobial activity of AMPs is known to be exerted primarily by permeation of the bacterial membrane, the mechanism underlying its anti-inflammatory activity remains to be elucidated. We report potent anti-inflammatory activity of WALK11.3, an antimicrobial model peptide with an amphipathic helical conformation, in lipopolysaccharide (LPS-stimulated RAW264.7 cells. This peptide inhibited the expression of inflammatory mediators, including nitric oxide, COX-2, IL-1β, IL-6, INF-β, and TNF-α. Although WALK11.3 did not exert a major effect on all downstream signaling in the MyD88-dependent pathway, toll-like receptor 4 (TLR4- mediated pro-inflammatory signals were markedly attenuated in the TRIF-dependent pathway due to inhibition of the phosphorylation of STAT1 by attenuation of IRF3 phosphorylation. WALK11.3 specifically inhibited the endocytosis of TLR4, which is essential for triggering TRIF-mediated signaling in macrophage cells. Hence, we suggest that specific interference with TLR4 endocytosis could be one of the major modes of the anti-inflammatory action of AMPs. Our designed WALK11 peptides, which possess both antimicrobial and anti-inflammatory activities, may be promising molecules for the development of therapies for infectious inflammation.

  6. Operational decisionmaking and action selection under psychological stress in nuclear power plants

    International Nuclear Information System (INIS)

    Gertman, D.I.; Haney, L.N.; Jenkins, J.P.; Blackman, H.S.

    1985-05-01

    An extensive review of literature on individual and group performance and decisionmaking under psychological stress was conducted and summarized. Specific stress-related variables relevant to reactor operation were pinpointed and incorporated in an experiment to assess the performance of reactor operators under psychological stress. The decisionmaking performance of 24 reactor operators under differing levels of workload, conflicting information, and detail of available written procedures was assessed in terms of selecting immediate, subsequent, and nonapplicable actions in response to 12 emergency scenarios resulting from a severe seismic event at a pressurized water reactor. Specific personality characteristics of the operators suggested by the literature to be related to performance under stress were assessed and correlated to decisionmaking under stress. The experimental results were statistically analyzed, and findings indicated that operator decisionmaking under stress was more accurate under lower levels of workload, with the availability of detailed procedures, and in the presence of high conflicting information

  7. Induction of osteoblast differentiation by selective activation of kinase-mediated actions of the estrogen receptor.

    Science.gov (United States)

    Kousteni, Stavroula; Almeida, Maria; Han, Li; Bellido, Teresita; Jilka, Robert L; Manolagas, Stavros C

    2007-02-01

    Estrogens control gene transcription by cis or trans interactions of the estrogen receptor (ER) with target DNA or via the activation of cytoplasmic kinases. We report that selective activation of kinase-mediated actions of the ER with 4-estren-3alpha,17beta-diol (estren) or an estradiol-dendrimer conjugate, each a synthetic compound that stimulates kinase-mediated ER actions 1,000 to 10,000 times more potently than direct DNA interactions, induced osteoblastic differentiation in established cell lines of uncommitted osteoblast precursors and primary cultures of osteoblast progenitors by stimulating Wnt and BMP-2 signaling in a kinase-dependent manner. In sharp contrast, 17beta-estradiol (E(2)) suppressed BMP-2-induced osteoblast progenitor commitment and differentiation. Consistent with the in vitro findings, estren, but not E(2), stimulated Wnt/beta-catenin-mediated transcription in T-cell factor-lacZ transgenic mice. Moreover, E(2) stimulated BMP signaling in mice in which ERalpha lacks DNA binding activity and classical estrogen response element-mediated transcription (ERalpha(NERKI/-)) but not in wild-type controls. This evidence reveals for the first time the existence of a large signalosome in which inputs from the ER, kinases, bone morphogenetic proteins, and Wnt signaling converge to induce differentiation of osteoblast precursors. ER can either induce it or repress it, depending on whether the activating ligand (and presumably the resulting conformation of the receptor protein) precludes or accommodates ERE-mediated transcription.

  8. Antistaphylococcal effect of enterocin AS-48 in bakery ingredients of vegetable origin, alone and in combination with selected antimicrobials.

    Science.gov (United States)

    Viedma, Pilar Martinez; Abriouel, Hikmate; Omar, Nabil Ben; López, Rosario Lucas; Gálvez, Antonio

    2009-09-01

    The inhibitory effect of enterocin AS-48 against Staphylococcus aureus was investigated in various types of bakery ingredients. Antibacterial activity greatly depended on the food substrate, ranging from complete inactivation of S. aureus in liquid caramel (in which the bacterium survived poorly) to no significant inhibition (as in vanilla or chocolate creams). Significant reductions of viable counts in the range of 1.8 to 2.7 log units (P enterocin AS-48 was tested in combination with other antimicrobials. Bactericidal activity increased markedly for the combinations of AS-48 and 0.1% eugenol (v/v), 0.5% 2-nitropropanol (v/v), or 3% Nisaplin (w/v). Enterocin AS-48 could be applied in combination with other antimicrobials for preservation of bakery ingredients against S. aureus.

  9. Conformational Flexibility Determines Selectivity and Antibacterial, Antiplasmodial, and Anticancer Potency of Cationic α-Helical Peptides*

    OpenAIRE

    Vermeer, Louic S.; Lan, Yun; Abbate, Vincenzo; Ruh, Emrah; Bui, Tam T.; Wilkinson, Louise J.; Kanno, Tokuwa; Jumagulova, Elmira; Kozlowska, Justyna; Patel, Jayneil; McIntyre, Caitlin A.; Yam, W. C.; Siu, Gilman; Atkinson, R. Andrew; Lam, Jenny K. W.

    2012-01-01

    Background: Antimicrobial peptides (AMPs) have the potential to act against multiple pathogenic targets. Results: AMPs that maintain conformational flexibility are more potent against multiple pathogens and less hemolytic. Conclusion: Antimicrobial action and hemolysis proceed via differing mechanisms. Significance: The potency, selectivity, and ability of AMPs to reach intracellular pathogens can be modulated using general principles.

  10. Alcohol-related biases in selective attention and action tendency make distinct contributions to dysregulated drinking behaviour.

    Science.gov (United States)

    Sharbanee, Jason M; Stritzke, Werner G K; Wiers, Reinout W; MacLeod, Colin

    2013-10-01

    To assess whether alcohol-related biases in selective-attention and action tendency uniquely or concurrently predict the ability to regulate alcohol consumption. Two groups of undergraduate social drinkers (total n = 55) who differed in their ability to regulate their alcohol consumption completed a novel Selective-Attention/Action-Tendency Task (SA/ATT), which assessed separately alcohol-related biases in selective attention and action tendency. University of Western Australia, Australia. Dysregulated drinking was operationalized as a self-reported high level of alcohol consumption on the Alcohol Consumption Questionnaire, and a high desire to reduce consumption on the Brief Readiness to Change Algorithm. Selective attention and action tendency were assessed using the SA/ATT, working memory was assessed using the operation-span task and participant characteristics were assessed using the Alcohol Use Disorders Identification Test (AUDIT) and Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES). Results indicated that (i) there was no significant association between alcohol-related biases in selective attention and action tendency, r = 0.16, P = 0.274, and (ii) biases towards alcohol, in both selective attention, β = 1.01, odds ratio = 2.74, P = 0.022, and action tendency, β = 1.24, odds ratio = 3.45, P = 0.015, predicted independent variance in dysregulated-drinker status. Biases in selective attention and action tendency appear to be distinct mechanisms that contribute independently to difficulty regulating alcohol consumption. Treatment components that could be combined to target both mechanisms could enhance treatment outcomes for alcohol-use disorders. © 2013 Society for the Study of Addiction.

  11. Antimicrobial usage and resistance in beef production

    OpenAIRE

    Cameron, Andrew; McAllister, Tim A.

    2016-01-01

    Antimicrobials are critical to contemporary high-intensity beef production. Many different antimicrobials are approved for beef cattle, and are used judiciously for animal welfare, and controversially, to promote growth and feed efficiency. Antimicrobial administration provides a powerful selective pressure that acts on the microbial community, selecting for resistance gene determinants and antimicrobial-resistant bacteria resident in the bovine flora. The bovine microbiota includes many harm...

  12. Where neuroscience and dynamic system theory meet autonomous robotics: a contracting basal ganglia model for action selection.

    Science.gov (United States)

    Girard, B; Tabareau, N; Pham, Q C; Berthoz, A; Slotine, J-J

    2008-05-01

    Action selection, the problem of choosing what to do next, is central to any autonomous agent architecture. We use here a multi-disciplinary approach at the convergence of neuroscience, dynamical system theory and autonomous robotics, in order to propose an efficient action selection mechanism based on a new model of the basal ganglia. We first describe new developments of contraction theory regarding locally projected dynamical systems. We exploit these results to design a stable computational model of the cortico-baso-thalamo-cortical loops. Based on recent anatomical data, we include usually neglected neural projections, which participate in performing accurate selection. Finally, the efficiency of this model as an autonomous robot action selection mechanism is assessed in a standard survival task. The model exhibits valuable dithering avoidance and energy-saving properties, when compared with a simple if-then-else decision rule.

  13. Evaluation and selection of Bacillus species based on enzyme production, antimicrobial activity and biofilm synthesis as direct-fed microbials candidates for poultry

    Directory of Open Access Journals (Sweden)

    Juan D Latorre

    2016-10-01

    Full Text Available Social concern about misuse of antibiotics as growth promoters (AGP and generation of multidrug-resistant bacteria have restricted the dietary inclusion of antibiotics in livestock feed in several countries. Direct-fed microbials (DFM are one of the multiple alternatives commonly evaluated as substitutes of AGP. Sporeformer bacteria from the genus Bacillus have been extensively investigated because of their extraordinary properties to form highly-resistant endospores, production of antimicrobial compounds and synthesize different exogenous enzymes. The purpose of the present study was to evaluate and select Bacillus spp. from environmental and poultry sources as DFM candidates, considering their enzyme production profile, biofilm synthesis capacity and pathogen-inhibition activity. Thirty one Bacillus isolates were screened for in vitro relative enzyme activity of amylase, protease, lipase and phytase using a selective media for each enzyme, with 3/31 strains selected as superior enzyme producers. These three isolates were identified as B. subtilis (1/3, and B. amyloliquefaciens (2/3 based on biochemical tests and 16S rRNA sequence analysis. For evaluation of biofilm synthesis, the generation of an adherent crystal violet-stained ring was determined in polypropylene tubes, resulting in 11/31 strains showing a strong biofilm formation. Moreover, all Bacillus strains were evaluated for growth inhibition activity against Salmonella enterica serovar Enteritidis (26/31, Escherichia coli (28/31 and Clostridioides difficile (29/31. Additionally, in previous in vitro and in vivo studies, these selected Bacillus strains have shown to be resistant to different biochemical conditions of the gastrointestinal tract of poultry. Results of the present study suggest that the selection and consumption of Bacillus-DFM, producing a variable set of enzymes and antimicrobial compounds may contribute to enhanced performance through improving nutrient digestibility

  14. Mushroom body output neurons encode valence and guide memory-based action selection in Drosophila

    Science.gov (United States)

    Aso, Yoshinori; Sitaraman, Divya; Ichinose, Toshiharu; Kaun, Karla R; Vogt, Katrin; Belliart-Guérin, Ghislain; Plaçais, Pierre-Yves; Robie, Alice A; Yamagata, Nobuhiro; Schnaitmann, Christopher; Rowell, William J; Johnston, Rebecca M; Ngo, Teri-T B; Chen, Nan; Korff, Wyatt; Nitabach, Michael N; Heberlein, Ulrike; Preat, Thomas; Branson, Kristin M; Tanimoto, Hiromu; Rubin, Gerald M

    2014-01-01

    Animals discriminate stimuli, learn their predictive value and use this knowledge to modify their behavior. In Drosophila, the mushroom body (MB) plays a key role in these processes. Sensory stimuli are sparsely represented by ∼2000 Kenyon cells, which converge onto 34 output neurons (MBONs) of 21 types. We studied the role of MBONs in several associative learning tasks and in sleep regulation, revealing the extent to which information flow is segregated into distinct channels and suggesting possible roles for the multi-layered MBON network. We also show that optogenetic activation of MBONs can, depending on cell type, induce repulsion or attraction in flies. The behavioral effects of MBON perturbation are combinatorial, suggesting that the MBON ensemble collectively represents valence. We propose that local, stimulus-specific dopaminergic modulation selectively alters the balance within the MBON network for those stimuli. Our results suggest that valence encoded by the MBON ensemble biases memory-based action selection. DOI: http://dx.doi.org/10.7554/eLife.04580.001 PMID:25535794

  15. The effects of freedom of choice in action selection on perceived mental effort and the sense of agency.

    Science.gov (United States)

    Barlas, Zeynep; Hockley, William E; Obhi, Sukhvinder S

    2017-10-01

    Previous research showed that increasing the number of action alternatives enhances the sense of agency (SoA). Here, we investigated whether choice space could affect subjective judgments of mental effort experienced during action selection and examined the link between subjective effort and the SoA. Participants performed freely selected (among two, three, or four options) and instructed actions that produced pleasant or unpleasant tones. We obtained action-effect interval estimates to quantify intentional binding - the perceived interval compression between actions and outcomes and feeling of control (FoC) ratings. Additionally, participants reported the degree of mental effort they experienced during action selection. We found that both binding and FoC were systematically enhanced with increasing choice-level. Outcome valence did not influence binding, while FoC was stronger for pleasant than unpleasant outcomes. Finally, freely chosen actions were associated with low subjective effort and slow responses (i.e., higher reaction times), and instructed actions were associated with high effort and fast responses. Although the conditions that yielded the greatest and least subjective effort also yielded the greatest and least binding and FoC, there was no significant correlation between subjective effort and SoA measures. Overall, our results raise interesting questions about how agency may be influenced by response selection demands (i.e., indexed by speed of responding) and subjective mental effort. Our work also highlights the importance of understanding how subjective mental effort and response speed are related to popular notions of fluency in response selection. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Antimicrobial usage and risk of retreatment for mild to moderate clinical mastitis cases on dairy farms following on-farm bacterial culture and selective therapy.

    Science.gov (United States)

    McDougall, S; Niethammer, J; Graham, E M

    2018-03-01

    To assess antimicrobial usage for treatment of mild to moderate clinical mastitis, and risk of retreatment, following implementation of an on-farm bacterial culture system and selective therapy based on culture results, and to assess compliance with treatment decision tree protocols and the level of agreement between results from on-farm culture and laboratory-based microbiology methods. Herdowners from seven dairy herds were asked to collect milk samples from cases of mild to moderate clinical mastitis between July 2015 and May 2016. All samples were cultured on-farm using a commercially available selective media and were also submitted for laboratory-based culture. Within sequential pairs of cows with mastitis, half were assigned to be treated without regard to culture results (Blanket group), and half were treated based on the on-farm culture results (Selective group) according to decision tree diagrams provided to the farmers. Culture results, treatments, and retreatments for clinical mastitis were recorded. The sum of the daily doses of antimicrobials used per cow, the number of retreatments and interval to first retreatment were compared between treatment groups. The geometric mean sum of daily doses for quarters assigned to the Selective (1.72 (95% CI=1.55-1.90)) group was lower than for the Blanket (2.38 (95% CI=2.17-2.60)) group (p=0.005). The percentage of cows retreated for clinical mastitis did not differ between the Selective (21.7 (95% CI=10.5-25.9)%) and Blanket (26.1 (95% CI=20.9-31.3)%) groups (p=0.13), and there was no difference between groups in the hazard that cows would be retreated within 60 days of enrolment (hazard ratio=0.82 (95% CI=0.39-1.69); p=0.59). Compliance with the treatment protocols was higher amongst quarters assigned to the Selective (199/233; 85.4%) compared with the Blanket (171/249; 68.7%) group (p<0.001), and varied between farms from 64-94%. The overall agreement between results from on-farm and laboratory culture was 188

  17. Antimicrobial compounds in tears.

    Science.gov (United States)

    McDermott, Alison M

    2013-12-01

    The tear film coats the cornea and conjunctiva and serves several important functions. It provides lubrication, prevents drying of the ocular surface epithelia, helps provide a smooth surface for refracting light, supplies oxygen and is an important component of the innate defense system of the eye providing protection against a range of potential pathogens. This review describes both classic antimicrobial compounds found in tears such as lysozyme and some more recently identified such as members of the cationic antimicrobial peptide family and surfactant protein-D as well as potential new candidate molecules that may contribute to antimicrobial protection. As is readily evident from the literature review herein, tears, like all mucosal fluids, contain a plethora of molecules with known antimicrobial effects. That all of these are active in vivo is debatable as many are present in low concentrations, may be influenced by other tear components such as the ionic environment, and antimicrobial action may be only one of several activities ascribed to the molecule. However, there are many studies showing synergistic/additive interactions between several of the tear antimicrobials and it is highly likely that cooperativity between molecules is the primary way tears are able to afford significant antimicrobial protection to the ocular surface in vivo. In addition to effects on pathogen growth and survival some tear components prevent epithelial cell invasion and promote the epithelial expression of innate defense molecules. Given the protective role of tears a number of scenarios can be envisaged that may affect the amount and/or activity of tear antimicrobials and hence compromise tear immunity. Two such situations, dry eye disease and contact lens wear, are discussed here. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. L-ALLIANCE: a mechanism for adaptive action selection in heterogeneous multi-robot teams

    Energy Technology Data Exchange (ETDEWEB)

    Parker, L.E.

    1995-11-01

    In practical applications of robotics, it is usually quite difficult, if not impossible, for the system designer to fully predict the environmental states in which the robots will operate. The complexity of the problem is further increased when dealing with teams of robots which themselves may be incompletely known and characterized in advance. It is thus highly desirable for robot teams to be able to adapt their performance during the mission due to changes in the environment, or to changes in other robot team members. In previous work, we introduced a behavior-based mechanism called the ALLIANCE architecture -- that facilitates the fault tolerant cooperative control of multi-robot teams. However, this previous work did not address the issue of how to dynamically update the control parameters during a mission to adapt to ongoing changes in the environment or in the robot team, and to ensure the efficiency of the collective team actions. In this paper, we address this issue by proposing the L-ALLIANCE mechanism, which defines an automated method whereby robots can use knowledge learned from previous experience to continually improve their collective action selection when working on missions composed of loosely coupled, discrete subtasks. This ability to dynamically update robotic control parameters provides a number of distinct advantages: it alleviates the need for human tuning of control parameters, it facilitates the use of custom-designed multi-robot teams for any given application, it improves the efficiency of the mission performance, and It allows robots to continually adapt their performance over time due to changes in the robot team and/or the environment. We describe the L-ALLIANCE mechanism, present the results of various alternative update strategies we investigated, present the formal model of the L-ALLIANCE mechanism, and present the results of a simple proof of concept implementation on a small team of heterogeneous mobile robots.

  19. Fitts's law in a selective reaching task: the proximity-to-hand effect of action-centered attention revisited.

    Science.gov (United States)

    Welsh, Timothy N; Zbinden, Michele

    2009-01-01

    The "proximity-to-hand" effect refers to the finding that distractors between the home position and the target cause more interference in a selective reaching movement than distractors farther from the home position. Based largely on the proximity-to-hand effect, Tipper, Lortie, and Baylis (1992) proposed that attention is distributed in an action-centered framework such that the interference caused by a specific stimulus depends on the action. The current experiments sought to determine if there is an attentional preference for stimuli closer to home or for stimuli that activate more efficiently executed actions regardless of the location. Results supported the latter hypothesis in that the greatest interference was observed when the distractor activated an action with a lower index of difficulty than the target, even though that distractor was farther from home than the target. These findings indicate that the action context mediates the influence that nontarget stimuli have on the processing of target responses.

  20. Regulation and regulatory role of WNT signaling in potentiating FSH action during bovine dominant follicle selection.

    Directory of Open Access Journals (Sweden)

    P S P Gupta

    Full Text Available Follicular development occurs in wave like patterns in monotocous species such as cattle and humans and is regulated by a complex interaction of gonadotropins with local intrafollicular regulatory molecules. To further elucidate potential mechanisms controlling dominant follicle selection, granulosa cell RNA harvested from F1 (largest and F2 (second largest follicles isolated at predeviation (PD and onset of diameter deviation (OD stages of the first follicular wave was subjected to preliminary RNA transcriptome analysis. Expression of numerous WNT system components was observed. Hence experiments were performed to test the hypothesis that WNT signaling modulates FSH action on granulosa cells during follicular waves. Abundance of mRNA for WNT pathway members was evaluated in granulosa cells harvested from follicles at emergence (EM, PD, OD and early dominance (ED stages of the first follicular wave. In F1 follicles, abundance of CTNNB1 and DVL1 mRNAs was higher and AXIN2 mRNA was lower at ED versus EM stages and DVL1 and FZD6 mRNAs were higher and AXIN2 mRNA was lower in F1 versus F2 follicle at the ED stage. Bovine granulosa cells were treated in vitro with increasing doses of the WNT inhibitor IWR-1+/- maximal stimulatory dose of FSH. IWR-1 treatment blocked the FSH-induced increase in granulosa cell numbers and reduced the FSH-induced increase in estradiol. Granulosa cells were also cultured in the presence or absence of FSH +/- IWR-1 and hormonal regulation of mRNA for WNT pathway members and known FSH targets determined. FSH treatment increased CYP19A1, CCND2, CTNNB1, AXIN2 and FZD6 mRNAs and the stimulatory effect on CYP19A1 mRNA was reduced by IWR-1. In contrast, FSH reduced CARTPT mRNA and IWR-1 partially reversed the inhibitory effect of FSH. Results support temporal and hormonal regulation and a potential role for WNT signaling in potentiating FSH action during dominant follicle selection.

  1. A moving story: Whole-body motor training selectively improves the appraisal of action meanings in naturalistic narratives.

    Science.gov (United States)

    Trevisan, Piergiorgio; Sedeño, Lucas; Birba, Agustina; Ibáñez, Agustín; García, Adolfo M

    2017-10-02

    This study examined whether systematic whole-body stimulation and increased attention to visuospatial motion patterns can enhance the appraisal of action meanings evoked by naturalistic texts. Participants listened to action and neutral (non-action) narratives before and after videogame-based bodily training, and responded to questions on information realized by verbs (denoting abstract and action processes) and circumstances (conveying locative or temporal details, for example). Strategically, we worked with dyslexic children, whose potential comprehension deficits could give room to post-training improvements. Results showed a selective boost in understanding of action information, even when controlling for baseline performance. Also, this effect proved uninfluenced by short-term memory skills, and it was absent when training relied on non-action videogames requiring minimal bodily engagement. Of note, the movements described in the texts did not match those performed by participants, suggesting that well-established effector- and direction-specific language embodiment effects may be accompanied by more coarse-grained sensorimotor resonance, driven by activation of motor and visuospatial sensory systems. In sum, the stimulation of movement-related mechanisms seems to selectively boost the appraisal of actions evoked by naturalistic texts. By demonstrating such links between two real-life activities, our study offers an empirical tie between embodied and situated accounts of cognition.

  2. In and out of control: brain mechanisms linking fluency of action selection to self-agency in patients with schizophrenia.

    Science.gov (United States)

    Voss, Martin; Chambon, Valérian; Wenke, Dorit; Kühn, Simone; Haggard, Patrick

    2017-08-01

    Sense of agency refers to the feeling of control over one's actions, and their consequences. It involves both predictive processes linked to action control, and retrospective 'sense-making' causal inferences. Schizophrenia has been associated with impaired predictive processing, but the underlying mechanisms that impair patients' sense of agency remain unclear. We introduce a new 'prospective' aspect of agency and show that subliminally priming an action not only influences response times, but also influences reported sense of agency over subsequent action outcomes. This effect of priming was associated with altered connectivity between frontal areas and the angular gyrus. The effects on response times and on frontal action selection mechanisms were similar in patients with schizophrenia and in healthy volunteers. However, patients showed no effects of priming on sense of agency, no priming-related activation of angular gyrus, and no priming-related changes in fronto-parietal connectivity. We suggest angular gyrus activation reflects the experiences of agency, or non-agency, in part by processing action selection signals generated in the frontal lobes. The altered action awareness that characterizes schizophrenia may be due to impaired communication between these areas. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Antimicrobial resistance

    DEFF Research Database (Denmark)

    Llor, Carl; Bjerrum, Lars

    2014-01-01

    Antimicrobial resistance is a global public health challenge, which has accelerated by the overuse of antibiotics worldwide. Increased antimicrobial resistance is the cause of severe infections, complications, longer hospital stays and increased mortality. Overprescribing of antibiotics......-the-counter sale of antibiotics, the use of antimicrobial stewardship programmes, the active participation of clinicians in audits, the utilization of valid rapid point-of-care tests, the promotion of delayed antibiotic prescribing strategies, the enhancement of communication skills with patients with the aid...

  4. Peptoid-Substituted Hybrid Antimicrobial Peptide Derived from Papiliocin and Magainin 2 with Enhanced Bacterial Selectivity and Anti-inflammatory Activity.

    Science.gov (United States)

    Shin, Areum; Lee, Eunjung; Jeon, Dasom; Park, Young-Guen; Bang, Jeong Kyu; Park, Yong-Sun; Shin, Song Yub; Kim, Yangmee

    2015-06-30

    Antimicrobial peptides (AMPs) are important components of the host innate immune system. Papiliocin is a 37-residue AMP purified from larvae of the swallowtail butterfly Papilio xuthus. Magainin 2 is a 23-residue AMP purified from the skin of the African clawed frog Xenopus laevis. We designed an 18-residue hybrid peptide (PapMA) incorporating N-terminal residues 1-8 of papiliocin and N-terminal residues 4-12 of magainin 2, joined by a proline (Pro) hinge. PapMA showed high antimicrobial activity but was cytotoxic to mammalian cells. To decrease PapMA cytotoxicity, we designed a lysine (Lys) peptoid analogue, PapMA-k, which retained high antimicrobial activity but displayed cytotoxicity lower than that of PapMA. Fluorescent dye leakage experiments and confocal microscopy showed that PapMA targeted bacterial cell membranes whereas PapMA-k penetrated bacterial cell membranes. Nuclear magnetic resonance experiments revealed that PapMA contained an N-terminal α-helix from Lys(3) to Lys(7) and a C-terminal α-helix from Lys(10) to Lys(17), with a Pro(9) hinge between them. PapMA-k also had two α-helical structures in the same region connected with a flexible hinge residue at Nlys(9), which existed in a dynamic equilibrium of cis and trans conformers. Using lipopolysaccharide-stimulated RAW264.7 macrophages, the anti-inflammatory activity of PapMA and PapMA-k was confirmed by inhibition of nitric oxide and inflammatory cytokine production. In addition, treatment with PapMA and PapMA-k decreased the level of ultraviolet irradiation-induced expression of genes encoding matrix metalloproteinase-1 (MMP-1), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in human keratinocyte HaCaT cells. Thus, PapMA and PapMA-k are potent peptide antibiotics with antimicrobial and anti-inflammatory activity, with PapMA-k displaying enhanced bacterial selectivity.

  5. Rapid Improvement in Visual Selective Attention Related to Action Video Gaming Experience

    Directory of Open Access Journals (Sweden)

    Nan Qiu

    2018-02-01

    Full Text Available A central issue in cognitive science is understanding how learning induces cognitive and neural plasticity, which helps illuminate the biological basis of learning. Research in the past few decades showed that action video gaming (AVG offered new, important perspectives on learning-related cognitive and neural plasticity. However, it is still unclear whether cognitive and neural plasticity is observable after a brief AVG session. Using behavioral and electrophysiological measures, this study examined the plasticity of visual selective attention (VSA associated with a 1 h AVG session. Both AVG experts and non-experts participated in this study. Their VSA was assessed prior to and after the AVG session. Within-group comparisons on the participants' performance before and after the AVG session showed improvements in response time in both groups and modulations of electrophysiological measures in the non-experts. Furthermore, between-group comparisons showed that the experts had superior VSA, relative to the non-experts, prior to the AVG session. These findings suggested an association between the plasticity of VSA and AVG. Most importantly, this study showed that the plasticity of VSA was observable after even a 1 h AVG session.

  6. Rapid Improvement in Visual Selective Attention Related to Action Video Gaming Experience.

    Science.gov (United States)

    Qiu, Nan; Ma, Weiyi; Fan, Xin; Zhang, Youjin; Li, Yi; Yan, Yuening; Zhou, Zhongliang; Li, Fali; Gong, Diankun; Yao, Dezhong

    2018-01-01

    A central issue in cognitive science is understanding how learning induces cognitive and neural plasticity, which helps illuminate the biological basis of learning. Research in the past few decades showed that action video gaming (AVG) offered new, important perspectives on learning-related cognitive and neural plasticity. However, it is still unclear whether cognitive and neural plasticity is observable after a brief AVG session. Using behavioral and electrophysiological measures, this study examined the plasticity of visual selective attention (VSA) associated with a 1 h AVG session. Both AVG experts and non-experts participated in this study. Their VSA was assessed prior to and after the AVG session. Within-group comparisons on the participants' performance before and after the AVG session showed improvements in response time in both groups and modulations of electrophysiological measures in the non-experts. Furthermore, between-group comparisons showed that the experts had superior VSA, relative to the non-experts, prior to the AVG session. These findings suggested an association between the plasticity of VSA and AVG. Most importantly, this study showed that the plasticity of VSA was observable after even a 1 h AVG session.

  7. Skeletal unloading induces selective resistance to the anabolic actions of growth hormone on bone

    Science.gov (United States)

    Halloran, B. P.; Bikle, D. D.; Harris, J.; Autry, C. P.; Currier, P. A.; Tanner, S.; Patterson-Buckendahl, P.; Morey-Holton, E.

    1995-01-01

    Loss of skeletal weight bearing or physical unloading of bone in the growing animal inhibits bone formation and induces a bone mineral deficit. To determine whether the inhibition of bone formation induced by skeletal unloading in the growing animal is a consequence of diminished sensitivity to growth hormone (GH) we studied the effects of skeletal unloading in young hypophysectomized rats treated with GH (0, 50, 500 micrograms/100 g body weight/day). Skeletal unloading reduced serum osteocalcin, impaired uptake of 3H-proline into bone, decreased proximal tibial mass, and diminished periosteal bone formation at the tibiofibular junction. When compared with animals receiving excipient alone, GH administration increased bone mass in all animals. The responses in serum osteocalcin, uptake of 3H-proline and 45Ca into the proximal tibia, and proximal tibial mass in non-weight bearing animals were equal to those in weight bearing animals. The responses in trabecular bone volume in the proximal tibia and bone formation at the tibiofibular junction to GH, however, were reduced significantly by skeletal unloading. Bone unloading prevented completely the increase in metaphyseal trabecular bone normally induced by GH and severely dampened the stimulatory effect (158% vs. 313%, p < 0.002) of GH on periosteal bone formation. These results suggest that while GH can stimulate the overall accumulation of bone mineral in both weight bearing and non-weight bearing animals, skeletal unloading selectively impairs the response of trabecular bone and periosteal bone formation to the anabolic actions of GH.

  8. ACTION OF UNIFORM SEARCH ALGORITHM WHEN SELECTING LANGUAGE UNITS IN THE PROCESS OF SPEECH

    Directory of Open Access Journals (Sweden)

    Ирина Михайловна Некипелова

    2013-05-01

    Full Text Available The article is devoted to research of action of uniform search algorithm when selecting by human of language units for speech produce. The process is connected with a speech optimization phenomenon. This makes it possible to shorten the time of cogitation something that human want to say, and to achieve the maximum precision in thoughts expression. The algorithm of uniform search works at consciousness  and subconsciousness levels. It favours the forming of automatism produce and perception of speech. Realization of human's cognitive potential in the process of communication starts up complicated mechanism of self-organization and self-regulation of language. In turn, it results in optimization of language system, servicing needs not only human's self-actualization but realization of communication in society. The method of problem-oriented search is used for researching of optimization mechanisms, which are distinctive to speech producing and stabilization of language.DOI: http://dx.doi.org/10.12731/2218-7405-2013-4-50

  9. Skeletal unloading induces selective resistance to the anabolic actions of growth hormone on bone

    Science.gov (United States)

    Halloran, B. P.; Bikle, D. D.; Harris, J.; Autry, C. P.; Currier, P. A.; Tanner, S.; Patterson-Buckendahl, P.; Morey-Holton, E.

    1995-01-01

    Loss of skeletal weight bearing or physical unloading of bone in the growing animal inhibits bone formation and induces a bone mineral deficit. To determine whether the inhibition of bone formation induced by skeletal unloading in the growing animal is a consequence of diminished sensitivity to growth hormone (GH) we studied the effects of skeletal unloading in young hypophysectomized rats treated with GH (0, 50, 500 micrograms/100 g body weight/day). Skeletal unloading reduced serum osteocalcin, impaired uptake of 3H-proline into bone, decreased proximal tibial mass, and diminished periosteal bone formation at the tibiofibular junction. When compared with animals receiving excipient alone, GH administration increased bone mass in all animals. The responses in serum osteocalcin, uptake of 3H-proline and 45Ca into the proximal tibia, and proximal tibial mass in non-weight bearing animals were equal to those in weight bearing animals. The responses in trabecular bone volume in the proximal tibia and bone formation at the tibiofibular junction to GH, however, were reduced significantly by skeletal unloading. Bone unloading prevented completely the increase in metaphyseal trabecular bone normally induced by GH and severely dampened the stimulatory effect (158% vs. 313%, p bone formation. These results suggest that while GH can stimulate the overall accumulation of bone mineral in both weight bearing and non-weight bearing animals, skeletal unloading selectively impairs the response of trabecular bone and periosteal bone formation to the anabolic actions of GH.

  10. Probabilistic measures of climate change vulnerability, adaptation action benefits, and related uncertainty from maximum temperature metric selection

    Science.gov (United States)

    DeWeber, Jefferson T.; Wagner, Tyler

    2018-01-01

    Predictions of the projected changes in species distributions and potential adaptation action benefits can help guide conservation actions. There is substantial uncertainty in projecting species distributions into an unknown future, however, which can undermine confidence in predictions or misdirect conservation actions if not properly considered. Recent studies have shown that the selection of alternative climate metrics describing very different climatic aspects (e.g., mean air temperature vs. mean precipitation) can be a substantial source of projection uncertainty. It is unclear, however, how much projection uncertainty might stem from selecting among highly correlated, ecologically similar climate metrics (e.g., maximum temperature in July, maximum 30‐day temperature) describing the same climatic aspect (e.g., maximum temperatures) known to limit a species’ distribution. It is also unclear how projection uncertainty might propagate into predictions of the potential benefits of adaptation actions that might lessen climate change effects. We provide probabilistic measures of climate change vulnerability, adaptation action benefits, and related uncertainty stemming from the selection of four maximum temperature metrics for brook trout (Salvelinus fontinalis), a cold‐water salmonid of conservation concern in the eastern United States. Projected losses in suitable stream length varied by as much as 20% among alternative maximum temperature metrics for mid‐century climate projections, which was similar to variation among three climate models. Similarly, the regional average predicted increase in brook trout occurrence probability under an adaptation action scenario of full riparian forest restoration varied by as much as .2 among metrics. Our use of Bayesian inference provides probabilistic measures of vulnerability and adaptation action benefits for individual stream reaches that properly address statistical uncertainty and can help guide conservation

  11. Probabilistic measures of climate change vulnerability, adaptation action benefits, and related uncertainty from maximum temperature metric selection.

    Science.gov (United States)

    DeWeber, Jefferson T; Wagner, Tyler

    2018-06-01

    Predictions of the projected changes in species distributions and potential adaptation action benefits can help guide conservation actions. There is substantial uncertainty in projecting species distributions into an unknown future, however, which can undermine confidence in predictions or misdirect conservation actions if not properly considered. Recent studies have shown that the selection of alternative climate metrics describing very different climatic aspects (e.g., mean air temperature vs. mean precipitation) can be a substantial source of projection uncertainty. It is unclear, however, how much projection uncertainty might stem from selecting among highly correlated, ecologically similar climate metrics (e.g., maximum temperature in July, maximum 30-day temperature) describing the same climatic aspect (e.g., maximum temperatures) known to limit a species' distribution. It is also unclear how projection uncertainty might propagate into predictions of the potential benefits of adaptation actions that might lessen climate change effects. We provide probabilistic measures of climate change vulnerability, adaptation action benefits, and related uncertainty stemming from the selection of four maximum temperature metrics for brook trout (Salvelinus fontinalis), a cold-water salmonid of conservation concern in the eastern United States. Projected losses in suitable stream length varied by as much as 20% among alternative maximum temperature metrics for mid-century climate projections, which was similar to variation among three climate models. Similarly, the regional average predicted increase in brook trout occurrence probability under an adaptation action scenario of full riparian forest restoration varied by as much as .2 among metrics. Our use of Bayesian inference provides probabilistic measures of vulnerability and adaptation action benefits for individual stream reaches that properly address statistical uncertainty and can help guide conservation actions. Our

  12. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing options ... of Animation of Antimicrobial Resistance More in Antimicrobial ... Antimicrobial Resistance Monitoring System About NARMS 2015 NARMS Integrated ...

  13. The SPIRIT Action Framework: A structured approach to selecting and testing strategies to increase the use of research in policy.

    Science.gov (United States)

    Redman, Sally; Turner, Tari; Davies, Huw; Williamson, Anna; Haynes, Abby; Brennan, Sue; Milat, Andrew; O'Connor, Denise; Blyth, Fiona; Jorm, Louisa; Green, Sally

    2015-07-01

    The recent proliferation of strategies designed to increase the use of research in health policy (knowledge exchange) demands better application of contemporary conceptual understandings of how research shapes policy. Predictive models, or action frameworks, are needed to organise existing knowledge and enable a more systematic approach to the selection and testing of intervention strategies. Useful action frameworks need to meet four criteria: have a clearly articulated purpose; be informed by existing knowledge; provide an organising structure to build new knowledge; and be capable of guiding the development and testing of interventions. This paper describes the development of the SPIRIT Action Framework. A literature search and interviews with policy makers identified modifiable factors likely to influence the use of research in policy. An iterative process was used to combine these factors into a pragmatic tool which meets the four criteria. The SPIRIT Action Framework can guide conceptually-informed practical decisions in the selection and testing of interventions to increase the use of research in policy. The SPIRIT Action Framework hypothesises that a catalyst is required for the use of research, the response to which is determined by the capacity of the organisation to engage with research. Where there is sufficient capacity, a series of research engagement actions might occur that facilitate research use. These hypotheses are being tested in ongoing empirical work. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Alcohol-paired contextual cues produce an immediate and selective loss of goal-directed action in rats

    Directory of Open Access Journals (Sweden)

    Sean B Ostlund

    2010-07-01

    Full Text Available We assessed whether the presence of contextual cues paired with alcohol would disrupt rats’ capacity to express appropriate goal-directed action control. Rats were first given differential context conditioning such that one set of contextual cues was paired with the injection of ethanol and a second, distinctive set of cues was paired with the injection of saline. All rats were then trained in a third, neutral context to press one lever for grain pellets and another lever for sucrose pellets. They were then given two extinction tests to evaluate their ability to choose between the two actions in response to the devaluation of one of the two food outcomes with one test conducted in the alcohol-paired context and the other conducted in the control (saline-paired context. In the control context, rats exhibited goal-directed action control; i.e., they were able selectively to withhold the action that previously earned the now devalued outcome. However, these same rats were impaired when tested in the alcohol-paired context, performing both actions at the same rate regardless of the current value of their respective outcomes. Subsequent testing revealed that the rats were capable of overcoming this impairment if they were giving response-contingent feedback about the current value of the food outcomes. These results provide a clear demonstration of the disruptive influence that alcohol-paired cues can exert on decision-making in general and goal-directed action selection and choice in particular.

  15. Uncovering effects of self-control and stimulus-driven action selection on the sense of agency.

    Science.gov (United States)

    Wang, Yuru; Damen, Tom G E; Aarts, Henk

    2017-10-01

    The sense of agency refers to feelings of causing one's own action and resulting effect. Previous research indicates that voluntary action selection is an important factor in shaping the sense of agency. Whereas the volitional nature of the sense of agency is well documented, the present study examined whether agency is modulated when action selection shifts from self-control to a more automatic stimulus-driven process. Seventy-two participants performed an auditory Simon task including congruent and incongruent trials to generate automatic stimulus-driven vs. more self-control driven action, respectively. Responses in the Simon task produced a tone and agency was assessed with the intentional binding task - an implicit measure of agency. Results showed a Simon effect and temporal binding effect. However, temporal binding was independent of congruency. These findings suggest that temporal binding, a window to the sense of agency, emerges for both automatic stimulus-driven actions and self-controlled actions. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Antimicrobial Peptides: A Promising Therapeutic Strategy in Tackling Antimicrobial Resistance.

    Science.gov (United States)

    Nuti, Ramya; Goud, Nerella S; Saraswati, A Prasanth; Alvala, Ravi; Alvala, Mallika

    2017-01-01

    Antimicrobial resistance (AMR) has posed a serious threat to global public health and it requires immediate action, preferably long term. Current drug therapies have failed to curb this menace due to the ability of microbes to circumvent the mechanisms through which the drugs act. From the drug discovery point of view, the majority of drugs currently employed for antimicrobial therapy are small molecules. Recent trends reveal a surge in the use of peptides as drug candidates as they offer remarkable advantages over small molecules. Newer synthetic strategies like organometalic complexes, Peptide-polymer conjugates, solid phase, liquid phase and recombinant DNA technology encouraging the use of peptides as therapeutic agents with a host of chemical functions, and tailored for specific applications. In the last decade, many peptide based drugs have been successfully approved by the Food and Drug Administration (FDA). This success can be attributed to their high specificity, selectivity and efficacy, high penetrability into the tissues, less immunogenicity and less tissue accumulation. Considering the enormity of AMR, the use of Antimicrobial Peptides (AMPs) can be a viable alternative to current therapeutics strategies. AMPs are naturally abundant allowing synthetic chemists to develop semi-synthetics peptide molecules. AMPs have a broad spectrum of activity towards microbes and they possess the ability to bypass the resistance induction mechanisms of microbes. The present review focuses on the potential applications of AMPs against various microbial disorders and their future prospects. Several resistance mechanisms and their strategies have also been discussed to highlight the importance in the current scenario. Breakthroughs in AMP designing, peptide synthesis and biotechnology have shown promise in tackling this challenge and has revived the interest of using AMPs as an important weapon in fighting AMR. Copyright© Bentham Science Publishers; For any queries

  17. On the relation between action selection and movement control in 5- to 9-month-old infants.

    NARCIS (Netherlands)

    van Wermeskerken, M; van der Kamp, J.; Savelsbergh, G.J.P.

    2011-01-01

    Although 5-month-old infants select action modes that are adaptive to the size of the object (i.e., one- or two-handed reaching), it has largely remained unclear whether infants of this age control the ensuing movement to the size of the object (i.e., scaling of the aperture between hands). We

  18. Determination of the minimum inhibitory concentration (MIC and mutant prevention concentration (MPC of selected antimicrobials in bovine and swine Pasteurella multocida, Escherichia coli, and Staphylococcus aureus isolates

    Directory of Open Access Journals (Sweden)

    Kateřina Nedbalcová

    2015-01-01

    Full Text Available We compared the values of the minimum inhibitory concentration (MIC and mutant prevention concentration (MPC values ​​of three antimicrobial agents for 72 bovine isolates of Pasteurella multocida, 80 swine isolates of P. multocida, 80 bovine isolates of Escherichia coli, 80 swine isolates of E. coli, and 80 isolates of Staphylococcus aureus from bovine mastitis. The ratio of MIC90​​/MPC90 which limited mutant selection window (MSW was ≤ 0.12/4 mg/l for enrofloxacin, 0.5/≥ 64 mg/l for florfenicol and 4/≥ 128 mg/l for tulathromycin in bovine P. multocida isolates, ≤ 0.12/2 mg/l for enrofloxacin, 0.5/≥ 64 mg/l for florfenicol and 4/≥ 128 mg/l for tulathromycin in swine P. multocida isolates, 1/16 mg/l for enrofloxacin, 8/≥ 64 mg/l for florfenicol and 8/≥ 128 mg/l for tulathromycin in bovine E. coli isolates, 0.5/16 mg/l for enrofloxacin, ≥ 64/≥ 64 mg/l for florfenicol and 8/≥ 128 mg/l for tulathromycin in swine E. coli isolates, and 0.25/16 mg/l for enrofloxacin, 4/≥ 64 mg/l for florfenicol and 4/≥ 128 mg/l for tulathromycin in S. aureus isolates. These findings indicate that the dosage of antimicrobial agents to achieve serum concentration equal to or higher than MPC could reduce selection of resistant bacterial subpopulation.

  19. Design of an Action Selection Mechanism for Cooperative Soccer Robots Based on Fuzzy Decision Making Algorithm

    Directory of Open Access Journals (Sweden)

    S. Alireza Mohades Kasaei

    2010-04-01

    Full Text Available Robocup is an international competition for multi agent research and related subject like: Artificial intelligence, Image processing, machine learning, robot path planning, control, and
    obstacle avoidance. In a soccer robot game, the environment is highly competitive and dynamic. In order to work in the dynamically changing environment, the decision-making system of a soccer robot system should have the features of flexibility and real-time adaptation. In this paper we will
    focus on the Middle Size Soccer Robot league (MSL and new hierarchical hybrid fuzzy methods for decision making and action selection of a robot in Middle Size Soccer Robot league (MSL are presented. First, the behaviors of an agent are introduced, implemented and classified in two layers,
    the Low_Level_Behaviors and the High_Level_Behaviors. In the second layer, a two phase mechanism for decision making is introduced. In phase one, some useful methods are implemented which check the robot’s situation for performing required behaviors. In the next phase, the team strategy, team formation, robot’s role and the robot’s positioning system are introduced. A fuzzy logical approach is employed to recognize the team strategy and further more to tell the player the
    best position to move. We believe that a Dynamic role engine is necessary for a successful team. Dynamic role engine and formation control during offensive or defensive play, help us to prevent collision avoidance among own players when attacking the ball and obstacle avoidance of the opponents. At last, we comprised our implemented algorithm in the Robocup 2007 and 2008 and results showed the efficiency of the introduced methodology. The results are satisfactory which has already been successfully implemented in ADRO RoboCup team. This project is still in progress and some new interesting methods are described in the current report.

  20. Nuclear facility decommissioning and site remedial actions: A selected bibliography: Volume 7

    International Nuclear Information System (INIS)

    Owen, P.T.; Michelson, D.C.; Knox, N.P.; Fowler, J.W.

    1986-09-01

    The 644 abstracted references on nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the seventh in a series of reports prepared annually for the US Department of Energy's Remedial Action Programs. Foreign and domestic literature of all types - technical reports, progress reports, journal articles, conference papers, symposium proceedings, theses, books, patents, legislation, and research project descriptions - has been included. The bibliography contains scientific (basic research as well as applied technology), economic, regulatory, and legal literature pertinent to the US Department of Energy's remedial action program. Major chapters are (1) Surplus Facilities Management Program, (2) Nuclear Facilities Decommissioning, (3) Formerly Utilized Sites Remedial Action Program, (4) Facilities Contaminated with Naturally Occurring Radionuclides, (5) Uranium Mill Tailings Remedial Action Program, (6) Grand Junction Remedial Action Program, (7) Uranium Mill Tailings Management, (8) Technical Measurements Center, and (9) General Remedial Action Program Studies. Chapter sections for chapters 1, 2, 5, and 7 include Design, Planning, and Regulations; Environmental Studies and Site Surveys; Health, Safety, and Biomedical Studies; Decontamination Studies; Dismantlement and Demolition; Site Stabilization and Reclamation; Waste Disposal; Remedial Action Experience; and General Studies. References are arranged alphabetically by leading author. Those references having no individual author are listed by corporate affiliation or by publication description. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, and keywords. The appendix contains a list of frequently used acronyms and abbreviations

  1. Where and how to manage: optimal selection of conservation actions for multiple species

    NARCIS (Netherlands)

    Teeffelen, van A.J.A.; Moilanen, A.

    2008-01-01

    Multiple alternative options are frequently available for the protection, maintenance or restoration of conservation areas. The choice of a particular management action can have large effects on the species occurring in the area, because different actions have different effects on different species.

  2. Nuclear facility decommissioning and site remedial actions. Volume 6. A selected bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Owen, P.T.; Michelson, D.C.; Knox, N.P.

    1985-09-01

    This bibliography of 683 references with abstracts on the subject of nuclear facility decommissioning, uranium mill tailings management, and site remedial actions is the sixth in a series of annual reports prepared for the US Department of Energy's Remedial Action Programs. Foreign as well as domestic literature of all types - technical reports, progress reports, journal articles, conference papers, symposium proceedings, theses, books, patents, legislation, and research project descriptions - has been included. The bibliography contains scientific (basic research as well as applied technology), economic, regulatory, and legal literature pertinent to the US Department of Energy's remedial action program. Major chapters are: (1) Surplus Facilities Management Program; (2) Nuclear Facilities Decommissioning; (3) Formerly Utilized Sites Remedial Action Program; (4) Facilities Contaminated with Natural Radioactivity; (5) Uranium Mill Tailings Remedial Action Program; (6) Grand Junction Remedial Action Program; (7) Uranium Mill Tailings Management; (8) Technical Measurements Center; and (9) General Remedial Action Program Studies. Chapter sections for chapters 1, 2, 5, and 7 include Design, Planning, and Regulations; Environmental Studies and Site Surveys; Health, Safety, and Biomedical Studies; Decontamination Studies; Dismantlement and Demolition; Site Stabilization and Reclamation; Waste Disposal; Remedial Action Experience; and General Studies. The references within each chapter or section are arranged alphabetically by leading author. References having no individual author are arranged by corporate affiliation or by publication description.

  3. Nuclear facility decommissioning and site remedial actions. Volume 6. A selected bibliography

    International Nuclear Information System (INIS)

    Owen, P.T.; Michelson, D.C.; Knox, N.P.

    1985-09-01

    This bibliography of 683 references with abstracts on the subject of nuclear facility decommissioning, uranium mill tailings management, and site remedial actions is the sixth in a series of annual reports prepared for the US Department of Energy's Remedial Action Programs. Foreign as well as domestic literature of all types - technical reports, progress reports, journal articles, conference papers, symposium proceedings, theses, books, patents, legislation, and research project descriptions - has been included. The bibliography contains scientific (basic research as well as applied technology), economic, regulatory, and legal literature pertinent to the US Department of Energy's remedial action program. Major chapters are: (1) Surplus Facilities Management Program; (2) Nuclear Facilities Decommissioning; (3) Formerly Utilized Sites Remedial Action Program; (4) Facilities Contaminated with Natural Radioactivity; (5) Uranium Mill Tailings Remedial Action Program; (6) Grand Junction Remedial Action Program; (7) Uranium Mill Tailings Management; (8) Technical Measurements Center; and (9) General Remedial Action Program Studies. Chapter sections for chapters 1, 2, 5, and 7 include Design, Planning, and Regulations; Environmental Studies and Site Surveys; Health, Safety, and Biomedical Studies; Decontamination Studies; Dismantlement and Demolition; Site Stabilization and Reclamation; Waste Disposal; Remedial Action Experience; and General Studies. The references within each chapter or section are arranged alphabetically by leading author. References having no individual author are arranged by corporate affiliation or by publication description

  4. Civil Society Action and Governance in Vietnam: Selected Findings from an Empirical Survey

    Directory of Open Access Journals (Sweden)

    Jörg Wischermann

    2010-01-01

    Full Text Available In this article, findings from 300 standardized interviews with representatives of Civic Organizations in Ho Chi Minh-City and Ha Noi are presented. Following a view of civil society as a specific mode of social action and interaction, data analysis unveils the existence of core dimensions of such action (respect, empathy/ sympathy, and the willingness to compromise and stick to agreed-upon rules, though the respective values of those dimensions vary strongly. Inseparably linked with such civil society action of whatever kind is consensus-seeking, an aversion to conflicts, and an affinity to synthesis. These attitudes and practices, dominating various Civic Organizations’ internal decision-making processes, represent elements of authoritarian political thinking in Civic Organizations’ leaders’ mindsets and courses of action. Combined, those characteristics make up civil society action “in Vietnamese colours”.

  5. Nuclear facility decommissioning and site remedial actions: a selected bibliography. Volume 5

    International Nuclear Information System (INIS)

    Owen, P.T.; Knox, N.P.; Chilton, B.D.; Baldauf, M.F.

    1984-09-01

    This bibliography of 756 references with abstracts on the subject of nuclear facility decommissioning, uranium mill tailings management, and site remedial actions is the fifth in a series of annual reports prepared for the US Department of Energy, Division of Remedial Action Projects. Foreign as well as domestic literature of all types - technical reports, progress reports, journal articles, conference papers, symposium proceedings, theses, books, patents, legislation, and research project descriptions - has been included in this publication. The bibliography contains scientific (basic research as well as applied technology), economic, regulatory, and legal literature pertinent to the US Department of Energy's Remedial Action Program. Major chapters are: (1) Surplus Facilities Management Program; (2) Nuclear Facilities Decommissioning; (3) Formerly Utilized Sites Remedial Action Program; (4) Uranium Mill Tailings Remedial Action Program; (5) Grand Junction Remedial Action Program; (6) Uranium Mill Tailings Management; and (7) Technical Measurements Center. Chapter sections for chapters 1, 2, 4, and 6 include Design, Planning, and Regulations; Environmental Studies and Site Surveys; Decontamination Studies; Dismantlement and Demolition; Site Stabilization and Reclamation; Waste Disposal; Remedial Action Experience; and General Studies. The references within each chapter or section are arranged alphabetically by leading author. References having no individual author are arranged by corporate author or by title. Indexes are provided for the categories of author, corporate affiliation, title, publication description, geographic location, and keywords. The Appendix contains a list of frequently used acronyms

  6. Nuclear Facilities Decommissioning and site remedial actions: a selected bibliography. Vol. 2

    International Nuclear Information System (INIS)

    Owen, P.T.; Fielden, J.M.; Knox, N.P.; Trotter, ES.

    1981-10-01

    This bibliography of 643 references represents the second in a series on nuclear facility decommissioning and site remedial actions to be produced by the Radiation Effects Information Center (REIC) within the Information Center Complex, Information Division, Oak Ridge National Laboratory. The bibliography contains scientific, technical, economic, and regulatory information pertaining to the US Department of Energy's Remedial Action Program. Major chapters are: Surplus Facilities Management Program; Nuclear Facilities Decommissioning; Formerly Utilized Sites Remedial Action Program; and Uranium Mill Tailings Management. The references within each chapter are arranged alphabetically by leading author. References having no individual author are arranged by corporate affiliation or by title. Indexes are provided for: (1) author; (2) corporate affiliation; (3) title; (4) publication description; (5) geographic location; and (6) keywords. The bibliography was compiled from a specialized data base established and maintained by REIC to provide information support for the US Department of Energy's Remedial Action Program, under the cosponsorship of its four major components: Surplus Facilities Management Program; Formerly Utilized Sites Remedial Action Program; Uranium Mill Tailings Remedial Action Program; and the Grand Junction Remedial Action Program

  7. Deep brain stimulation of the subthalamic nucleus modulates reward processing and action selection in Parkinson patients.

    Science.gov (United States)

    Wagenbreth, Caroline; Zaehle, Tino; Galazky, Imke; Voges, Jürgen; Guitart-Masip, Marc; Heinze, Hans-Jochen; Düzel, Emrah

    2015-06-01

    Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an effective treatment for motor impairments in Parkinson's disease (PD) but its effect on the motivational regulation of action control is still not fully understood. We investigated whether DBS of the STN influences the ability of PD patients to act for anticipated reward or loss, or whether DBS improves action execution independent of motivational valence. 16 PD patients (12 male, mean age = 58.5 ± 10.17 years) treated with bilateral STN-DBS and an age- and gender-matched group of healthy controls (HC) performed a go/no-go task whose contingencies explicitly decouple valence and action. Patients were tested with (ON) and without (OFF) active STN stimulation. For HC, there was a benefit in performing rewarded actions when compared to actions that avoided punishment. PD patients showed such a benefit reliably only when STN stimulation was ON. In fact, the relative behavioral benefit for go for reward over go to avoid losing was stronger in the PD patients under DBS ON than in HC. In PD patients, rather than generally improving motor functions independent of motivational valence, modulation of the STN by DBS improves action execution specifically when rewards are anticipated. Thus, STN-DBS establishes a reliable congruency between action and reward ("Pavlovian congruency") and remarkably enhances it over the level observed in HC.

  8. Nuclear facility decommissioning and site remedial actions: a selected bibliography. Volume 5

    Energy Technology Data Exchange (ETDEWEB)

    Owen, P.T.; Knox, N.P.; Chilton, B.D.; Baldauf, M.F.

    1984-09-01

    This bibliography of 756 references with abstracts on the subject of nuclear facility decommissioning, uranium mill tailings management, and site remedial actions is the fifth in a series of annual reports prepared for the US Department of Energy, Division of Remedial Action Projects. Foreign as well as domestic literature of all types - technical reports, progress reports, journal articles, conference papers, symposium proceedings, theses, books, patents, legislation, and research project descriptions - has been included in this publication. The bibliography contains scientific (basic research as well as applied technology), economic, regulatory, and legal literature pertinent to the US Department of Energy's Remedial Action Program. Major chapters are: (1) Surplus Facilities Management Program; (2) Nuclear Facilities Decommissioning; (3) Formerly Utilized Sites Remedial Action Program; (4) Uranium Mill Tailings Remedial Action Program; (5) Grand Junction Remedial Action Program; (6) Uranium Mill Tailings Management; and (7) Technical Measurements Center. Chapter sections for chapters 1, 2, 4, and 6 include Design, Planning, and Regulations; Environmental Studies and Site Surveys; Decontamination Studies; Dismantlement and Demolition; Site Stabilization and Reclamation; Waste Disposal; Remedial Action Experience; and General Studies. The references within each chapter or section are arranged alphabetically by leading author. References having no individual author are arranged by corporate author or by title. Indexes are provided for the categories of author, corporate affiliation, title, publication description, geographic location, and keywords. The Appendix contains a list of frequently used acronyms.

  9. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Durango, Colorado: Remedial action selection report

    International Nuclear Information System (INIS)

    1991-12-01

    The uranium mill tailings site near Durango, Colorado, was one of 24 inactive uranium mill sites designated to be remediated by the US Department of Energy (DOE) under the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA). Part of the UMTRCA requires that the US Nuclear Regulatory Commission (NRC) concur with the DOE's Remedial Action Plan (RAP) and certify that the remedial action conducted at the site complies with the standards promulgated by the US Environmental Protection Agency (EPA). Included in the RAP is this Remedial Action Selection Report (RAS), which has been developed to serve a two-fold purpose. First, it describes the activities that have been conducted by the DOE to accomplish remediation and long-term stabilization and control of the radioactive materials at the inactive uranium mill processing site near Durango, Colorado. Secondly, this document and the rest of the RAP, upon concurrence and execution by the DOE, the State of Colorado, and the NRC, become Appendix B of the Cooperative Agreement between the DOE and the State of Colorado

  10. Nuclear facility decommissioning and site remedial actions: A selected bibliography, Volume 13: Part 2, Indexes

    Energy Technology Data Exchange (ETDEWEB)

    Goins, L.F.; Webb, J.R.; Cravens, C.D.; Mallory, P.K.

    1992-09-01

    This is part 2 of a bibliography on nuclear facility decommissioning and site remedial action. This report contains indexes on the following: authors, corporate affiliation, title words, publication description, geographic location, subject category, and key word.

  11. Rational over-imitation: Preschoolers consider material costs and copy causally irrelevant actions selectively.

    Science.gov (United States)

    Keupp, Stefanie; Bancken, Christin; Schillmöller, Jelka; Rakoczy, Hannes; Behne, Tanya

    2016-02-01

    Children's strong tendency to over-imitate - i.e., to reproduce causally irrelevant actions - presents a well-documented, yet puzzling, phenomenon. On first sight this instrumentally inefficient behavior seems maladaptive and different accounts have been put forward to explain it. Causal accounts claim that children are misled by an adult's demonstration, mistake the superfluous actions as causally necessary, and therefore imitate them. Other accounts emphasize cognitive-motivational aspects underlying over-imitation, e.g. social motivations to affiliate with the model, or to adhere to normative conventions. Since all accounts predict the occurrence of over-imitation under typical conditions, different parameters and circumstances have to be considered to distinguish between them. Thus, we investigated children's over-imitation and their spontaneous verbal reactions to a puppet's behavior, in contexts in which a causally irrelevant action either led to the destruction of a valuable object belonging to the experimenter, or not. In addition, children saw the full action sequence being demonstrated either with an instrumental or a conventional focus. Causal accounts predict no flexibility across these contexts, because over-imitation is said to occur automatically. Normative accounts claim that different normative considerations affect children's behavior and action parsing, and therefore predict different response patterns across conditions. We found that over-imitation was less frequent in costly and instrumental conditions. Children criticized the puppet for omitting irrelevant actions more often in the non-costly condition, but criticized her more often for performing irrelevant actions in the costly condition, often expressing their moral concern. The results support the rational normative action interpretation account of over-imitation. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Selective activation of heteromeric SK channels contributes to action potential repolarization in mouse atrial myocytes.

    Science.gov (United States)

    Hancock, Jane M; Weatherall, Kate L; Choisy, Stéphanie C; James, Andrew F; Hancox, Jules C; Marrion, Neil V

    2015-05-01

    Activation of small conductance calcium-activated potassium (SK) channels is proposed to contribute to repolarization of the action potential in atrial myocytes. This role is controversial, as these cardiac SK channels appear to exhibit an uncharacteristic pharmacology. The objectives of this study were to resolve whether activation of SK channels contributes to atrial action potential repolarization and to determine the likely subunit composition of the channel. The effect of 2 SK channel inhibitors was assessed on outward current evoked in voltage clamp and on action potential duration in perforated patch and whole-cell current clamp recording from acutely isolated mouse atrial myocytes. The presence of SK channel subunits was assessed using immunocytochemistry. A significant component of outward current was reduced by the SK channel blockers apamin and UCL1684. Block by apamin displayed a sensitivity indicating that this current was carried by homomeric SK2 channels. Action potential duration was significantly prolonged by UCL1684, but not by apamin. This effect was accompanied by an increase in beat-to-beat variability and action potential triangulation. This pharmacology was matched by that of expressed heteromeric SK2-SK3 channels in HEK293 cells. Immunocytochemistry showed that atrial myocytes express both SK2 and SK3 channels with an overlapping expression pattern. Only proposed heteromeric SK2-SK3 channels are physiologically activated to contribute to action potential repolarization, which is indicated by the difference in pharmacology of evoked outward current and prolongation of atrial action potential duration. The effect of blocking this channel on the action potential suggests that SK channel inhibition during cardiac function has the potential to be proarrhythmic. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  13. Antimicrobial Properties of Selected Copper Alloys on Staphylococcus aureus and Escherichia coli in Different Simulations of Environmental Conditions: With vs. without Organic Contamination

    Directory of Open Access Journals (Sweden)

    Anna Różańska

    2017-07-01

    Full Text Available Background: Hospital equipment made from copper alloys can play an important role in complementing traditional methods of disinfection. Aims of the study: The aim of this study was to assess the dynamics of the antimicrobial properties of selected copper alloys in different simulations of environmental conditions (with organic contamination vs. without organic contamination, and to test alternatives to the currently used testing methods. Materials and Methods: A modification of Japanese standard JIS Z 2801 as well as Staphylococcus aureus (SA and Escherichia coli (EC suspended in NaCl vs. tryptic soy broth (TSB were used in tests performed on seven commonly used copper alloys, copper, and stainless steel. Results: A much faster reduction of the bacterial suspension was observed for the inoculum prepared in NaCl than in TSB. A faster reduction for EC than for SA was observed in the inoculum prepared in NaCl. The opposite results were found for the inoculum based on TSB. A significant correlation between the copper concentration in the copper alloys and the time and degree of bacterial suspension reduction was only observed in the case of EC. Conclusions: This study confirmed the antimicrobial properties of copper alloys, and additionally showed that Staphylococcus aureus was more resistant than Escherichia coli in the variant of the experiment without organic contamination. However, even for SA, a total reduction of the bacterial inoculum’s density took no longer than 2 h. Under conditions simulating organic contamination, all of the tested alloys were shown to have bactericidal or bacteriostatic properties, which was contrary to the results from stainless steel.

  14. Antimicrobial Properties of Selected Copper Alloys on Staphylococcus aureus and Escherichia coli in Different Simulations of Environmental Conditions: With vs. without Organic Contamination.

    Science.gov (United States)

    Różańska, Anna; Chmielarczyk, Agnieszka; Romaniszyn, Dorota; Sroka-Oleksiak, Agnieszka; Bulanda, Małgorzata; Walkowicz, Monika; Osuch, Piotr; Knych, Tadeusz

    2017-07-20

    Background: Hospital equipment made from copper alloys can play an important role in complementing traditional methods of disinfection. Aims of the study: The aim of this study was to assess the dynamics of the antimicrobial properties of selected copper alloys in different simulations of environmental conditions (with organic contamination vs. without organic contamination), and to test alternatives to the currently used testing methods. Materials and Methods: A modification of Japanese standard JIS Z 2801 as well as Staphylococcus aureus (SA) and Escherichia coli (EC) suspended in NaCl vs. tryptic soy broth (TSB) were used in tests performed on seven commonly used copper alloys, copper, and stainless steel. Results: A much faster reduction of the bacterial suspension was observed for the inoculum prepared in NaCl than in TSB. A faster reduction for EC than for SA was observed in the inoculum prepared in NaCl. The opposite results were found for the inoculum based on TSB. A significant correlation between the copper concentration in the copper alloys and the time and degree of bacterial suspension reduction was only observed in the case of EC. Conclusions: This study confirmed the antimicrobial properties of copper alloys, and additionally showed that Staphylococcus aureus was more resistant than Escherichia coli in the variant of the experiment without organic contamination. However, even for SA, a total reduction of the bacterial inoculum's density took no longer than 2 h. Under conditions simulating organic contamination, all of the tested alloys were shown to have bactericidal or bacteriostatic properties, which was contrary to the results from stainless steel.

  15. Nuclear facility decommissioning and site remedial actions: A selected bibliography: Volume 8

    Energy Technology Data Exchange (ETDEWEB)

    Owen, P.T.; Michelson, D.C.; Knox, N.P.

    1987-09-01

    The 553 abstracted references on nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the eighth in a series of reports. Foreign and domestic literature of all types - technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions - has been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of energy's remedial action program. Major chapters are Surplus Facilities Management Program, Nuclear Facilities Decommissioning, Formerly Utilized Sites Remedial Action Program, Facilities Contaminated with Naturally Occurring Radionuclides, Uranium Mill Tailings Remedial Action Program, Uranium Mill Tailings Management, Technical Measurements Center, and General Remedial Action Program Studies. Chapter sections for chapters 1, 2, 5, and 6 include Design, Planning, and Regulations; Environmental Studies and Site Surveys; Health, Safety, and Biomedical Studies; Decontamination Studies; Dismantlement and Demolition; Site Stabilization and Reclamation; Waste Disposal; Remedial Action Experience; and General Studies. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication description. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, and keywords. The appendix contains a list of frequently used acronyms and abbreviations.

  16. Nuclear facility decommissioning and site remedial actions: A selected bibliography: Volume 8

    International Nuclear Information System (INIS)

    Owen, P.T.; Michelson, D.C.; Knox, N.P.

    1987-09-01

    The 553 abstracted references on nuclear facility decommissioning, uranium mill tailings management, and site remedial actions constitute the eighth in a series of reports. Foreign and domestic literature of all types - technical reports, progress reports, journal articles, symposia proceedings, theses, books, patents, legislation, and research project descriptions - has been included. The bibliography contains scientific, technical, economic, regulatory, and legal information pertinent to the US Department of energy's remedial action program. Major chapters are Surplus Facilities Management Program, Nuclear Facilities Decommissioning, Formerly Utilized Sites Remedial Action Program, Facilities Contaminated with Naturally Occurring Radionuclides, Uranium Mill Tailings Remedial Action Program, Uranium Mill Tailings Management, Technical Measurements Center, and General Remedial Action Program Studies. Chapter sections for chapters 1, 2, 5, and 6 include Design, Planning, and Regulations; Environmental Studies and Site Surveys; Health, Safety, and Biomedical Studies; Decontamination Studies; Dismantlement and Demolition; Site Stabilization and Reclamation; Waste Disposal; Remedial Action Experience; and General Studies. Within these categories, references are arranged alphabetically by first author. Those references having no individual author are listed by corporate affiliation or by publication description. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, and keywords. The appendix contains a list of frequently used acronyms and abbreviations

  17. Optogenetic stimulation in a computational model of the basal ganglia biases action selection and reward prediction error.

    Science.gov (United States)

    Berthet, Pierre; Lansner, Anders

    2014-01-01

    Optogenetic stimulation of specific types of medium spiny neurons (MSNs) in the striatum has been shown to bias the selection of mice in a two choices task. This shift is dependent on the localisation and on the intensity of the stimulation but also on the recent reward history. We have implemented a way to simulate this increased activity produced by the optical flash in our computational model of the basal ganglia (BG). This abstract model features the direct and indirect pathways commonly described in biology, and a reward prediction pathway (RP). The framework is similar to Actor-Critic methods and to the ventral/dorsal distinction in the striatum. We thus investigated the impact on the selection caused by an added stimulation in each of the three pathways. We were able to reproduce in our model the bias in action selection observed in mice. Our results also showed that biasing the reward prediction is sufficient to create a modification in the action selection. However, we had to increase the percentage of trials with stimulation relative to that in experiments in order to impact the selection. We found that increasing only the reward prediction had a different effect if the stimulation in RP was action dependent (only for a specific action) or not. We further looked at the evolution of the change in the weights depending on the stage of learning within a block. A bias in RP impacts the plasticity differently depending on that stage but also on the outcome. It remains to experimentally test how the dopaminergic neurons are affected by specific stimulations of neurons in the striatum and to relate data to predictions of our model.

  18. Antimicrobial resistance in the 21st century: a multifaceted challenge.

    Science.gov (United States)

    Nolte, O

    2014-04-01

    Antimicrobial resistance, the ability of (pathogenic) bacteria to withstand the action of antibiotic drugs, has recently been rated of having an impact on humans similar to that of global climate change. Indeed, during the last years medicine has faced the development of highly resistant bacterial strains, which were, as a consequence of worldwide travel activity, dispersed all over the globe. This is even more astonishing if taking into account that antibiotics were introduced into human medicine not even hundred years ago. Resistance covers different principle aspects, natural resistance, acquired resistance and clinical resistance. In the modern microbiology laboratory, antimicrobial resistance is determined by measuring the susceptibility of micro-organisms in vitro in the presence of antimicrobials. However, since the efficacy of an antibiotic depends on its pharmacokinetic and pharmacodynamics properties, breakpoints are provided to translate minimal inhibitory concentration to categorical efficacy (i.e. susceptible or resistant). Resistance in one microorganism against one particular drug may drive treatment decisions of clinicians, thereby fostering selection pressure to resistance development against another antibiotic. Thereby, bacteria may acquire more and more resistance traits, ending up with multi-resistance. To this end, antimicrobial resistance becomes a public health concern, not only in terms of limited treatment options but also due to its economic burden. The current paper provides a summary of the main topics associated with antimicrobial resistance as an introduction to this special issue.

  19. Optimization and high-throughput screening of antimicrobial peptides.

    Science.gov (United States)

    Blondelle, Sylvie E; Lohner, Karl

    2010-01-01

    While a well-established process for lead compound discovery in for-profit companies, high-throughput screening is becoming more popular in basic and applied research settings in academia. The development of combinatorial libraries combined with easy and less expensive access to new technologies have greatly contributed to the implementation of high-throughput screening in academic laboratories. While such techniques were earlier applied to simple assays involving single targets or based on binding affinity, they have now been extended to more complex systems such as whole cell-based assays. In particular, the urgent need for new antimicrobial compounds that would overcome the rapid rise of drug-resistant microorganisms, where multiple target assays or cell-based assays are often required, has forced scientists to focus onto high-throughput technologies. Based on their existence in natural host defense systems and their different mode of action relative to commercial antibiotics, antimicrobial peptides represent a new hope in discovering novel antibiotics against multi-resistant bacteria. The ease of generating peptide libraries in different formats has allowed a rapid adaptation of high-throughput assays to the search for novel antimicrobial peptides. Similarly, the availability nowadays of high-quantity and high-quality antimicrobial peptide data has permitted the development of predictive algorithms to facilitate the optimization process. This review summarizes the various library formats that lead to de novo antimicrobial peptide sequences as well as the latest structural knowledge and optimization processes aimed at improving the peptides selectivity.

  20. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... video) Animation of Antimicrobial Resistance (text version) Arabic Translation of Animation of Antimicrobial Resistance Chinese Translation of Animation of Antimicrobial Resistance French Translation of ...

  1. Selectivity of Inhibition of N-Succinyl-l,l-Diaminopimelic Acid Desuccinylase in Bacteria: The product of dapE-gene Is Not the Target of l-Captopril Antimicrobial Activity.

    Science.gov (United States)

    Uda, Narasimha Rao; Creus, Marc

    2011-01-01

    The emergence of bacterial strains that are resistant to virtually all currently available antibiotics underscores the importance of developing new antimicrobial compounds. N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE) is a metallohydrolase involved in the meso-diaminopimelate (mDAP)/lysine biosynthetic pathway necessary for lysine biosynthesis and for building the peptidoglycan cell wall. Because DapE is essential for Gram-negative and some Gram-positive bacteria, DapE has been proposed as a good target for antibiotic development. Recently, l-captopril has been suggested as a lead compound for inhibition of DapE, although its selectivity for this enzyme target in bacteria remains unclear (Gillner et al. (2009)). Here, we tested the selectivity of l-captopril against DapE in bacteria. Since DapE knockout strains of gram-negative bacteria are viable upon chemical supplementation with mDAP, we reasoned that the antimicrobial activity of compounds targeting DapE should be abolished in mDAP-containing media. Although l-captopril had modest antimicrobial activity in Escherichia coli and in Salmonella enterica, to our surprise, inhibition of bacterial growth was independent both of mDAP supplementation and DapE over-expression. We conclude that DapE is not the main target of l-captopril inhibition in these bacteria. The methods implemented here will be useful for screening DapE-selective antimicrobial compounds directly in bacterial cultures.

  2. Infectious bronchitis corona virus establishes productive infection in avian macrophages interfering with selected antimicrobial functions.

    Directory of Open Access Journals (Sweden)

    Aruna Amarasinghe

    Full Text Available Infectious bronchitis virus (IBV causes respiratory disease leading to loss of egg and meat production in chickens. Although it is known that macrophage numbers are elevated in the respiratory tract of IBV infected chickens, the role played by macrophages in IBV infection, particularly as a target cell for viral replication, is unknown. In this study, first, we investigated the ability of IBV to establish productive replication in macrophages in lungs and trachea in vivo and in macrophage cell cultures in vitro using two pathogenic IBV strains. Using a double immunofluorescent technique, we observed that both IBV Massachusetts-type 41 (M41 and Connecticut A5968 (Conn A5968 strains replicate in avian macrophages at a low level in vivo. This in vivo observation was substantiated by demonstrating IBV antigens in macrophages following in vitro IBV infection. Further, IBV productive infection in macrophages was confirmed by demonstrating corona viral particles in macrophages and IBV ribonucleic acid (RNA in culture supernatants. Evaluation of the functions of macrophages following infection of macrophages with IBV M41 and Conn A5968 strains revealed that the production of antimicrobial molecule, nitric oxide (NO is inhibited. It was also noted that replication of IBV M41 and Conn A5968 strains in macrophages does not interfere with the induction of type 1 IFN activity by macrophages. In conclusion, both M41 and Con A5968 IBV strains infect macrophages in vivo and in vitro resulting productive replications. During the replication of IBV in macrophages, their ability to produce NO can be affected without affecting the ability to induce type 1 IFN activity. Further studies are warranted to uncover the significance of macrophage infection of IBV in the pathogenesis of IBV infection in chickens.

  3. Antimicrobial Pesticides

    Science.gov (United States)

    EPA regulates pesticides under the statutory authority of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). The registration requirements for antimicrobial pesticides differ somewhat from those of other pesticides. Find out more.

  4. Antimicrobials, stress and mutagenesis.

    Directory of Open Access Journals (Sweden)

    Alexandro Rodríguez-Rojas

    2014-10-01

    Full Text Available Cationic antimicrobial peptides are ancient and ubiquitous immune effectors that multicellular organisms use to kill and police microbes whereas antibiotics are mostly employed by microorganisms. As antimicrobial peptides (AMPs mostly target the cell wall, a microbial 'Achilles heel', it has been proposed that bacterial resistance evolution is very unlikely and hence AMPs are ancient 'weapons' of multicellular organisms. Here we provide a new hypothesis to explain the widespread distribution of AMPs amongst multicellular organism. Studying five antimicrobial peptides from vertebrates and insects, we show, using a classic Luria-Delbrück fluctuation assay, that cationic antimicrobial peptides (AMPs do not increase bacterial mutation rates. Moreover, using rtPCR and disc diffusion assays we find that AMPs do not elicit SOS or rpoS bacterial stress pathways. This is in contrast to the main classes of antibiotics that elevate mutagenesis via eliciting the SOS and rpoS pathways. The notion of the 'Achilles heel' has been challenged by experimental selection for AMP-resistance, but our findings offer a new perspective on the evolutionary success of AMPs. Employing AMPs seems advantageous for multicellular organisms, as it does not fuel the adaptation of bacteria to their immune defenses. This has important consequences for our understanding of host-microbe interactions, the evolution of innate immune defenses, and also sheds new light on antimicrobial resistance evolution and the use of AMPs as drugs.

  5. Antimicrobial Agents Used in Endodontic Treatment

    Directory of Open Access Journals (Sweden)

    Marina George Kudiyirickal

    2008-01-01

    Full Text Available Biomechanical preparation alone does not completely eradicate microorganisms from the root canal, hence the next logical step is to perform root canal procedures in conjunction with antimicrobials. The use of an antimicrobial agent improves the efficacy and prognosis of endodontic treatment. This review enumerates the most widely used antimicrobial agents, their mechanism of action and their potential use in reducing the microbial load.

  6. Nuclear facility decommissioning and site remedial actions: A selected bibliography, Volume 13: Part 1, Main text

    Energy Technology Data Exchange (ETDEWEB)

    Goins, L.F.; Webb, J.R.; Cravens, C.D.; Mallory, P.K.

    1992-09-01

    This publication contains 1035 abstracted references on environmental restoration, nuclear facility decommissioning, uranium mill tailings management, and site remedial actions. These citations constitute the thirteenth in a series of reports prepared annually for the US Department of Energy (DOE) Environmental Restoration programs. Citations to foreign and domestic literature of all types. There are 13 major sections of the publication, including: (1) DOE Decontamination and Decommissioning Program; (2) Nuclear Facilities Decommissioning; (3) DOE Formerly Utilized Sites Remedial Action Program; (4) DOE Uranium Mill Tailings Remedial Action Project; (5) Uranium Mill Tailings Management; (6) DOE Environmental Restoration Program; (7) DOE Site-Specific Remedial Actions; (8) Contaminated Site Restoration; (9) Remediation of Contaminated Soil and Groundwater; (10) Environmental Data Measurements, Management, and Evaluation; (11) Remedial Action Assessment and Decision-Making; (12) Technology Development and Evaluation; and (13) Environmental and Waste Management Issues. Bibliographic references are arranged in nine subject categories by geographic location and then alphabetically by first author, corporate affiliation, or publication title. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, subject category, and key word.

  7. Selective weighting of action-related feature dimensions in visual working memory.

    Science.gov (United States)

    Heuer, Anna; Schubö, Anna

    2017-08-01

    Planning an action primes feature dimensions that are relevant for that particular action, increasing the impact of these dimensions on perceptual processing. Here, we investigated whether action planning also affects the short-term maintenance of visual information. In a combined memory and movement task, participants were to memorize items defined by size or color while preparing either a grasping or a pointing movement. Whereas size is a relevant feature dimension for grasping, color can be used to localize the goal object and guide a pointing movement. The results showed that memory for items defined by size was better during the preparation of a grasping movement than during the preparation of a pointing movement. Conversely, memory for color tended to be better when a pointing movement rather than a grasping movement was being planned. This pattern was not only observed when the memory task was embedded within the preparation period of the movement, but also when the movement to be performed was only indicated during the retention interval of the memory task. These findings reveal that a weighting of information in visual working memory according to action relevance can even be implemented at the representational level during maintenance, demonstrating that our actions continue to influence visual processing beyond the perceptual stage.

  8. Nuclear facility decommissioning and site remedial actions: A selected bibliography, Volume 13: Part 1, Main text

    International Nuclear Information System (INIS)

    Goins, L.F.; Webb, J.R.; Cravens, C.D.; Mallory, P.K.

    1992-09-01

    This publication contains 1035 abstracted references on environmental restoration, nuclear facility decommissioning, uranium mill tailings management, and site remedial actions. These citations constitute the thirteenth in a series of reports prepared annually for the US Department of Energy (DOE) Environmental Restoration programs. Citations to foreign and domestic literature of all types. There are 13 major sections of the publication, including: (1) DOE Decontamination and Decommissioning Program; (2) Nuclear Facilities Decommissioning; (3) DOE Formerly Utilized Sites Remedial Action Program; (4) DOE Uranium Mill Tailings Remedial Action Project; (5) Uranium Mill Tailings Management; (6) DOE Environmental Restoration Program; (7) DOE Site-Specific Remedial Actions; (8) Contaminated Site Restoration; (9) Remediation of Contaminated Soil and Groundwater; (10) Environmental Data Measurements, Management, and Evaluation; (11) Remedial Action Assessment and Decision-Making; (12) Technology Development and Evaluation; and (13) Environmental and Waste Management Issues. Bibliographic references are arranged in nine subject categories by geographic location and then alphabetically by first author, corporate affiliation, or publication title. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, subject category, and key word

  9. Catching moving objects : Differential effects of background motion on action mode selection and movement control in 6- to 10-month-old infants

    NARCIS (Netherlands)

    van Wermeskerken, Margot; van der Kamp, John; Hoozemans, Marco J M; Savelsbergh, Geert J P

    2015-01-01

    In human adults the use of visual information for selecting appropriate modes for action appears to be separate from the use of visual information for the control of movements of which the action is composed (Milner & Goodale, [1995] The visual brain in action; [2008] Neuropsychologia 46:774-785).

  10. Catching moving objects: Differential effects of background motion on action mode selection and movement control in 6- to 10-month-old infants

    NARCIS (Netherlands)

    van Wermeskerken, M; van der Kamp, J.; Hoozemans, M.J.M.; Savelsbergh, G.J.P.

    2015-01-01

    In human adults the use of visual information for selecting appropriate modes for action appears to be separate from the use of visual information for the control of movements of which the action is composed (Milner & Goodale, [1995] The visual brain in action; [2008] Neuropsychologia 46:774-785).

  11. Nuclear facility decommissioning and site remedial actions: a selected bibliography. Volume 4

    International Nuclear Information System (INIS)

    Owen, P.T.; Knox, N.P.; Fielden, J.M.; Faust, R.A.

    1983-09-01

    This bibliography of 657 references with abstracts on the subject of nuclear facility decommissioning, uranium mill tailings management, and site remedial actions is the fourth in a series of annual reports prepared for the US Department of Energy, Division of Remedial Action Projects. Foreign as well as domestic documents of all types - technical reports, progress reports, journal articles, conference papers, symposium proceedings, theses, books, patents, legislation, and research project descriptions - have been references in this publication. The bibliography contains scientific (basic research as well as applied technology), economic, regulatory, and legal literature pertinent to the US Department of Energy's Remedial Action Program. Major chapters are: (1) Surplus Facilities Management Program; (2) Nuclear Facilities Decommissioning; (3) Formerly Utilized Sites Remedial Action Program; (4) Uranium Mill Tailings Remedial Action Program; (5) Grand Junction Remedial Action Program; and (6) Uranium Mill Tailings Management. Chapter sections for chapters 1 and 2 include: Design, Planning, and Regulations; Site Surveys; Decontamination Studies; Dismantlement and Demolition; Land Decontamination and Reclamation; Waste Disposal; and General studies. The references within each chapter or section are arranged alphabetically by leading author. References having no individual author are arranged by corporate author, or by title. Indexes are provided for the categories of author, corporate affiliation, title, publication description, geographic location, and keywords. Appendix A lists 264 bibliographic references to literature identified during this reporting period but not abstracted due to time constraints. Title and publication description indexes are given for this appendix. Appendix B defines frequently used acronyms, and Appendix C lists the recipients of this report according to their corporate affiliation

  12. Nuclear facility decommissioning and site remedial actions: a selected bibliography. Volume 4

    Energy Technology Data Exchange (ETDEWEB)

    Owen, P.T.; Knox, N.P.; Fielden, J.M.; Faust, R.A.

    1983-09-01

    This bibliography of 657 references with abstracts on the subject of nuclear facility decommissioning, uranium mill tailings management, and site remedial actions is the fourth in a series of annual reports prepared for the US Department of Energy, Division of Remedial Action Projects. Foreign as well as domestic documents of all types - technical reports, progress reports, journal articles, conference papers, symposium proceedings, theses, books, patents, legislation, and research project descriptions - have been references in this publication. The bibliography contains scientific (basic research as well as applied technology), economic, regulatory, and legal literature pertinent to the US Department of Energy's Remedial Action Program. Major chapters are: (1) Surplus Facilities Management Program; (2) Nuclear Facilities Decommissioning; (3) Formerly Utilized Sites Remedial Action Program; (4) Uranium Mill Tailings Remedial Action Program; (5) Grand Junction Remedial Action Program; and (6) Uranium Mill Tailings Management. Chapter sections for chapters 1 and 2 include: Design, Planning, and Regulations; Site Surveys; Decontamination Studies; Dismantlement and Demolition; Land Decontamination and Reclamation; Waste Disposal; and General studies. The references within each chapter or section are arranged alphabetically by leading author. References having no individual author are arranged by corporate author, or by title. Indexes are provided for the categories of author, corporate affiliation, title, publication description, geographic location, and keywords. Appendix A lists 264 bibliographic references to literature identified during this reporting period but not abstracted due to time constraints. Title and publication description indexes are given for this appendix. Appendix B defines frequently used acronyms, and Appendix C lists the recipients of this report according to their corporate affiliation.

  13. Action semantics: A unifying conceptual framework for the selective use of multimodal and modality-specific object knowledge.

    Science.gov (United States)

    van Elk, Michiel; van Schie, Hein; Bekkering, Harold

    2014-06-01

    Our capacity to use tools and objects is often considered one of the hallmarks of the human species. Many objects greatly extend our bodily capabilities to act in the physical world, such as when using a hammer or a saw. In addition, humans have the remarkable capability to use objects in a flexible fashion and to combine multiple objects in complex actions. We prepare coffee, cook dinner and drive our car. In this review we propose that humans have developed declarative and procedural knowledge, i.e. action semantics that enables us to use objects in a meaningful way. A state-of-the-art review of research on object use is provided, involving behavioral, developmental, neuropsychological and neuroimaging studies. We show that research in each of these domains is characterized by similar discussions regarding (1) the role of object affordances, (2) the relation between goals and means in object use and (3) the functional and neural organization of action semantics. We propose a novel conceptual framework of action semantics to address these issues and to integrate the previous findings. We argue that action semantics entails both multimodal object representations and modality-specific sub-systems, involving manipulation knowledge, functional knowledge and representations of the sensory and proprioceptive consequences of object use. Furthermore, we argue that action semantics are hierarchically organized and selectively activated and used depending on the action intention of the actor and the current task context. Our framework presents an integrative account of multiple findings and perspectives on object use that may guide future studies in this interdisciplinary domain. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Pre-SMA gray-matter density predicts individual differences in action selection in the face of conscious and unconscious response conflict

    NARCIS (Netherlands)

    van Gaal, S.; Scholte, H.S.; Lamme, V.A.F.; Fahrenfort, J.J.; Ridderinkhof, K.R.

    2011-01-01

    The presupplementary motor area (pre-SMA) is considered key in contributing to voluntary action selection during response conflict. Here we test whether individual differences in the ability to select appropriate actions in the face of strong (conscious) and weak (virtually unconscious) distracting

  15. Changing Preschool Children's Attitudes into Behavior towards Selected Environmental Issues: An Action Research Study

    Science.gov (United States)

    Ertürk Kara, Gözde; Aydos, E. Hande; Aydin, Özge

    2015-01-01

    The purpose of this study is to provide the transform of attitudes into behavior of 60-72 month of age children continued early childhood education toward environmental issues. Collaborative action research method of qualitative design was used. The whole participants of the study were 60-72 months of age children who were attending in an early…

  16. Adapting interaction environments to diverse users through online action set selection

    CSIR Research Space (South Africa)

    Hassan Mahmud, MM

    2014-06-01

    Full Text Available their personal optimum. We introduce a new class of problem in interface personalization where the task of the adaptive interface is to choose the subset of actions of the full interface to present to the user. In formalizing this problem, we model the user as a...

  17. Antimicrobial resistance issues in beef production

    Science.gov (United States)

    Antimicrobial resistance threats to human health as identified have been recognized as a critical global public health concern. Linkage of some threats to beef production is discussed. The relevance to beef production of recent government actions will be examined. Prominent antimicrobial resistance ...

  18. Seeing the World through Another Person's Eyes: Simulating Selective Attention via Action Observation

    Science.gov (United States)

    Frischen, Alexandra; Loach, Daniel; Tipper, Steven P.

    2009-01-01

    Selective attention is usually considered an egocentric mechanism, biasing sensory information based on its behavioural relevance to oneself. This study provides evidence for an equivalent allocentric mechanism that allows passive observers to selectively attend to information from the perspective of another person. In a negative priming task,…

  19. The risk of some veterinary antimicrobial agents on public health associated with antimicrobial resistance and their molecular basis

    OpenAIRE

    Haihong Hao; Zahid Iqbal; Yulian Wang; Guyue Cheng; Zong-Hui Yuan

    2016-01-01

    The risk of antimicrobial agents used in food-producing animals on public health associated with antimicrobial resistance continues to be a current topic of discussion as related to animal and human public health. In the present review, resistance monitoring data and risk assessment result of some important antimicrobial agents were cited to elucidate the possible association of antimicrobial use in food animals and antimicrobial resistance in human. From the selected examples, it was obvious...

  20. Chemical Composition, Antimicrobial Activity, and Mode of Action of Essential Oils against Paenibacillus larvae, Etiological Agent of American Foulbrood on Apis mellifera.

    Science.gov (United States)

    Pellegrini, María C; Alonso-Salces, Rosa M; Umpierrez, María L; Rossini, Carmen; Fuselli, Sandra R

    2017-04-01

    This study aimed to characterize the chemical composition of Aloysia polystachia, Acantholippia seriphioides, Schinus molle, Solidago chilensis, Lippia turbinata, Minthostachys mollis, Buddleja globosa, and Baccharis latifolia essential oils (EOs), and to evaluate their antibacterial activities and their capacity to provoke membrane disruption in Paenibacillus larvae, the bacteria that causes the American Foulbrood (AFB) disease on honey bee larvae. The relationship between the composition of the EOs and these activities on P. larvae was also analyzed. Monoterpenes were the most abundant compounds in all EOs. All EOs showed antimicrobial activity against P. larvae and disrupted the cell wall and cytoplasmic membrane of P. larvae provoking the leakage of cytoplasmic constituents (with the exception of B. latifolia EO). While, the EOs' antimicrobial activity was correlated most strongly to the content of pulegone, carvone, (Z)-β-ocimene, δ-cadinene, camphene, terpinen-4-ol, elemol, β-pinene, β-elemene, γ-cadinene, α-terpineol, and bornyl acetate; the volatiles that better explained the membrane disruption were carvone, limonene, cis-carvone oxide, pentadecane, trans-carvyl acetate, trans-carvone oxide, trans-limonene oxide, artemisia ketone, trans-carveol, thymol, and γ-terpinene (positively correlated) and biciclogermacrene, δ-2-carene, verbenol, α-pinene, and α-thujene (negatively correlated). The studied EOs are proposed as natural alternative means of control for the AFB disease. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  1. Antimicrobial action and anti-corrosion effect against sulfate reducing bacteria by lemongrass (Cymbopogon citratus) essential oil and its major component, the citral.

    Science.gov (United States)

    Korenblum, Elisa; Regina de Vasconcelos Goulart, Fátima; de Almeida Rodrigues, Igor; Abreu, Fernanda; Lins, Ulysses; Alves, Péricles Barreto; Blank, Arie Fitzgerald; Valoni, Erika; Sebastián, Gina V; Alviano, Daniela Sales; Alviano, Celuta Sales; Seldin, Lucy

    2013-08-10

    The anti-corrosion effect and the antimicrobial activity of lemongrass essential oil (LEO) against the planktonic and sessile growth of a sulfate reducing bacterium (SRB) were evaluated. Minimum inhibitory concentration (MIC) of LEO and its major component, the citral, was 0.17 mg ml-1. In addition, both LEO and citral showed an immediate killing effect against SRB in liquid medium, suggesting that citral is responsible for the antimicrobial activity of LEO against SRB. Transmission electron microscopy revealed that the MIC of LEO caused discernible cell membrane alterations and formed electron-dense inclusions. Neither biofilm formation nor corrosion was observed on carbon steel coupons after LEO treatment. LEO was effective for the control of the planktonic and sessile SRB growth and for the protection of carbon steel coupons against biocorrosion. The application of LEO as a potential biocide for SRB growth control in petroleum reservoirs and, consequently, for souring prevention, and/or as a coating protection against biocorrosion is of great interest for the petroleum industries.

  2. Antimicrobial action and anti-corrosion effect against sulfate reducing bacteria by lemongrass (Cymbopogon citratus) essential oil and its major component, the citral

    Science.gov (United States)

    2013-01-01

    The anti-corrosion effect and the antimicrobial activity of lemongrass essential oil (LEO) against the planktonic and sessile growth of a sulfate reducing bacterium (SRB) were evaluated. Minimum inhibitory concentration (MIC) of LEO and its major component, the citral, was 0.17 mg ml-1. In addition, both LEO and citral showed an immediate killing effect against SRB in liquid medium, suggesting that citral is responsible for the antimicrobial activity of LEO against SRB. Transmission electron microscopy revealed that the MIC of LEO caused discernible cell membrane alterations and formed electron-dense inclusions. Neither biofilm formation nor corrosion was observed on carbon steel coupons after LEO treatment. LEO was effective for the control of the planktonic and sessile SRB growth and for the protection of carbon steel coupons against biocorrosion. The application of LEO as a potential biocide for SRB growth control in petroleum reservoirs and, consequently, for souring prevention, and/or as a coating protection against biocorrosion is of great interest for the petroleum industries. PMID:23938023

  3. Chemical Profiling and Evaluation of Antioxidant and Anti-Microbial Properties of Selected Commercial Essential Oils: A Comparative Study

    OpenAIRE

    Lu?s, ?ngelo; Duarte, Ana Paula; Pereira, Lu?sa; Domingues, Fernanda

    2017-01-01

    Background: The last decades have seen an increased awareness by the scientific community of the extent of resistance to conventional antibiotics, particularly with respect to the emerging multidrug-resistant pathogenic microbes. Additionally, natural antioxidants have received significant attention among food professionals and consumers because of their assumed safety and potential therapeutic value. The aim of this work was to assess the antioxidant activities of eight selected commercial e...

  4. Antimicrobial Effect of Filipendula ulmaria Plant Extract Against Selected Foodborne Pathogenic and Spoilage Bacteria in Laboratory Media, Fish Flesh and Fish Roe Product

    Directory of Open Access Journals (Sweden)

    Charalampos Proestos

    2011-01-01

    Full Text Available Water-methanol extract from Filipendula ulmaria contains a variety of phenolic compounds, such as caffeic, p-coumaric and vanillic acid, myricetin, etc, which demonstrate antibacterial activity. Monitoring this activity in the broth using absorbance measurements showed that species of the Enterobacteriaceae family were more resistant than other Gram-negative and Gram-positive bacteria tested. Acidic environment enhanced the antibacterial activity of Filipendula ulmaria extract when it was tested against Salmonella Enteritidis PT4 and Listeria monocytogenes Scott A. The efficacy of Filipendula ulmaria extract against selected foodborne psychrotrophic bacteria was also tested using solid laboratory media and low incubation temperatures for better simulation of food preservation conditions. Higher concentrations of the extract, compared to minimum inhibitory concentration determined in the broth, were needed for satisfactory inhibition of spoilage bacteria. Potential use of Filipendula ulmaria extract as natural food preservative was also examined against natural spoilage flora and inoculated pathogenic bacteria on fish flesh and fish roe product (tarama salad. No significant differences of viable populations of spoilage or pathogenic bacteria were found between the treated samples and controls. Further trials of Filipendula ulmaria extract should be carried out in acidic foods with low fat and protein content, supplemented with additional adjuncts, in order to explore its potential as effective natural food antimicrobial agent.

  5. Aqueous and Organic Solvent-Extracts of Selected South African Medicinal Plants Possess Antimicrobial Activity against Drug-Resistant Strains of Helicobacter pylori: Inhibitory and Bactericidal Potential

    Directory of Open Access Journals (Sweden)

    Collise Njume

    2011-09-01

    Full Text Available The aim of this study was to identify sources of cheap starting materials for the synthesis of new drugs against Helicobacter pylori. Solvent-extracts of selected medicinal plants; Combretum molle, Sclerocarya birrea, Garcinia kola, Alepidea amatymbica and a single Strychnos species were investigated against 30 clinical strains of H. pylori alongside a reference control strain (NCTC 11638 using standard microbiological techniques. Metronidazole and amoxicillin were included in these experiments as positive control antibiotics. All the plants demonstrated anti-H. pylori activity with zone diameters of inhibition between 0 and 38 mm and 50% minimum inhibitory concentration (MIC50 values ranging from 0.06 to 5.0 mg/mL. MIC50 values for amoxicillin and metronidazole ranged from 0.001 to 0.63 mg/mL and 0.004 to 5.0 mg/mL respectively. The acetone extracts of C. molle and S. birrea exhibited a remarkable bactericidal activity against H. pylori killing more than 50% of the strains within 18 h at 4× MIC and complete elimination of the organisms within 24 h. Their antimicrobial activity was comparable to the control antibiotics. However, the activity of the ethanol extract of G. kola was lower than amoxicillin (P < 0.05 as opposed to metronidazole (P > 0.05. These results demonstrate that S. birrea, C. molle and G. kola may represent good sources of compounds with anti-H. pylori activity.

  6. Supplier Selection Proces: An Investigation and Implementation Action at Construction/Building Company

    OpenAIRE

    Hensmit, Andre

    2008-01-01

    The investigation was carried out to identify and understand the key characteristic of supplier selection that is to be considered in the real experience by Construction Company in South East Asia, especially Indonesia. The goal of this project focuses on the selection supplier process and its approaches, how the company performing the co-partnership relationship with suppliers, and as well find out the reason fro accomplishing these factors. The project involves interviewing a company in Ind...

  7. Antimicrobial Stewardship and Urinary Tract Infections

    Directory of Open Access Journals (Sweden)

    Lilian M. Abbo

    2014-05-01

    Full Text Available Urinary tract infections are the most common bacterial infections encountered in ambulatory and long-term care settings in the United States. Urine samples are the largest single category of specimens received by most microbiology laboratories and many such cultures are collected from patients who have no or questionable urinary symptoms. Unfortunately, antimicrobials are often prescribed inappropriately in such patients. Antimicrobial use, whether appropriate or inappropriate, is associated with the selection for antimicrobial-resistant organisms colonizing or infecting the urinary tract. Infections caused by antimicrobial-resistant organisms are associated with higher rates of treatment failures, prolonged hospitalizations, increased costs and mortality. Antimicrobial stewardship consists of avoidance of antimicrobials when appropriate and, when antimicrobials are indicated, use of strategies to optimize the selection, dosing, route of administration, duration and timing of antimicrobial therapy to maximize clinical cure while limiting the unintended consequences of antimicrobial use, including toxicity and selection of resistant microorganisms. This article reviews successful antimicrobial stewardship strategies in the diagnosis and treatment of urinary tract infections.

  8. Comparative analysis of selected methods for the assessment of antimicrobial and membrane-permeabilizing activity: a case study for lactoferricin derived peptides

    Directory of Open Access Journals (Sweden)

    Lohner Karl

    2008-11-01

    Full Text Available Abstract Background Growing concerns about bacterial resistance to antibiotics have prompted the development of alternative therapies like those based on cationic antimicrobial peptides (APs. These compounds not only are bactericidal by themselves but also enhance the activity of antibiotics. Studies focused on the systematic characterization of APs are hampered by the lack of standard guidelines for testing these compounds. We investigated whether the information provided by methods commonly used for the biological characterization of APs is comparable, as it is often assumed. For this purpose, we determined the bacteriostatic, bactericidal, and permeability-increasing activity of synthetic peptides (n = 57; 9–13 amino acid residues in length analogous to the lipopolysaccharide-binding region of human lactoferricin by a number of the most frequently used methods and carried out a comparative analysis. Results While the minimum inhibitory concentration determined by an automated turbidimetry-based system (Bioscreen or by conventional broth microdilution methods did not differ significantly, bactericidal activity measured under static conditions in a low-ionic strength solvent resulted in a vast overestimation of antimicrobial activity. Under these conditions the degree of antagonism between the peptides and the divalent cations differed greatly depending on the bacterial strain tested. In contrast, the bioactivity of peptides was not affected by the type of plasticware (polypropylene vs. polystyrene. Susceptibility testing of APs using cation adjusted Mueller-Hinton was the most stringent screening method, although it may overlook potentially interesting peptides. Permeability assays based on sensitization to hydrophobic antibiotics provided overall information analogous – though not quantitatively comparable- to that of tests based on the uptake of hydrophobic fluorescent probes. Conclusion We demonstrate that subtle changes in methods for

  9. Influence of gamma radiation on molluscicidal and antimicrobial action of leaf and stem bark of Ziziphus joazeiro; Influencia da radiacao gama sobre a acao moluscicida e antimicrobiana da folha e casca do caule de Ziziphus joazeiro

    Energy Technology Data Exchange (ETDEWEB)

    Mendes, Fabricio O.; Siqueira, Williams N.; Lima, Maira V.; Melo, Larissa S.A.; Luna Filho, Ricardo L.C.; Morais, Vinicius H.T.; Oliveira, Maria L.M.; Melo, Ana M.M.A.; Silva, Edvane B., E-mail: fabriciomendesbio@gmail.com, E-mail: williams.wns@gmail.com, E-mail: mairavasconceloslima@gmail.com, E-mail: larissamelo.pe@gmail.com, E-mail: ricardolclf@hotmail.com, E-mail: viniciushtmorais@hotmail.com, E-mail: mluizamarinho@gmail.com, E-mail: amdemelo@hotmail.com, E-mail: s, E-mail: fabriciomendesbio@gmail.com, E-mail: williams.wns@gmail.com, E-mail: edvborges@yahoo.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2017-11-01

    Ionizing radiation is a physical agent used in several areas of knowledge: in medicine for the diagnosis and treatment of diseases, in the industry, it is apply in the generation of energy, sterilization of equipment and food, for example. Studies show that radiation can modify the molecular structure of substances of natural origin, potentiating or inactivating their function. The compounds derived from plants have received special attention because they constitute a form of medicinal therapy that has been growing notably in recent years. In addition, products of natural origin may also aid in the control of microbiological or animal vectors of parasites. Of the various species of plants being studied, Ziziphus joazeiro, popularly known as jua, native to the Caatinga, is commercially exploited for the manufacture of cosmetics and as anti-inflammatory, antimicrobial, anti influenza, fever and gastritis, bruises and has molluscicidal activity. Therefore, the objective of this work was to evaluate the influence of cobalt-60 gamma radiation on leaf and bark extracts of Z. joazeiro stem, evaluating possible changes in molluscicidal and antimicrobial action. For the experiments, the Z joazeiro extracts were irradiated with doses of 5, 7.5 and 10 kGy (Gammacell-Cobalt-60, dose rate 7.222 kGy/h). Adult mollusks (n = 60) and embryos (n = 1800) of Biomphalaria glabrata were distributed in the following groups: negative control 1 (water only); negative control 2 (extract only); positive control (CuCO{sub 3}); and three groups submitted to irradiated extracts. The antibacterial assay was performed with Gram-positive microorganisms (Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis, Enterococcus faecalis) belonging to the collection of the Departamento de Antibioticos of the UFPE by disc diffusion method. Statistical analysis was perform by Student's t-test and chi-square test, with a confidence interval of 95%. The results showed that the ionizing radiation

  10. Probabilistic risk model to assess the potential for resistance selection following the use of anti-microbial medicated feed in pigs.

    Science.gov (United States)

    Filippitzi, Maria Eleni; Chantziaras, Ilias; Devreese, Mathias; Dewulf, Jeroen

    2018-05-30

    The cross-contamination of non-medicated feed with residues of anti-microbials (AM) causes a public and animal health concern associated with the potential for selection and dissemination of resistance. To analyse the associated risks, a probabilistic model was built using @Risk® (Palisade Corporation®) to show the potential extent of the effect of cross-contaminated pig feed on resistance selection. The results of the model include estimations of the proportion of pigs per production stage with residues of doxycycline, chlortetracycline, sulfadiazine and trimethoprim in their intestinal contents, as a result of exposure to cross-contaminated feed with different carry-over levels, in Belgium. By using a semi-quantitative approach, these estimations were combined with experimental data on AM concentrations associated with potential for resistance-selection pressure. Based on this model, it is estimated that 7.76% (min = 1.67; max = 36.94) of sows, 4.23% (min = 1.01%; max = 18.78%) of piglets and 2.8% (min = 0.51%; max = 14.9%) of fatteners in Belgium have residues of doxycycline in their intestinal tract due to consumption of feed with at least 1% carry-over. These values were estimated to be almost triple for sulfadiazine, but substantially lower for chlortetracycline and trimethoprim. Doxycycline concentrations as low as 1 mg/L (corresponding to consumed feed with at least 1% carry-over) can select for resistant porcine commensal Escherichia coli in vitro and in vivo. Conclusions on this risk could not be drawn for other AM at this stage, due to the lack of data on concentrations associated with resistance development. However, since the possibility of resistance mechanisms (e.g. co-selection) occurring cannot be excluded, the results of this model highlight that the use of AM medicated feed should be minimised where possible. In case of medicated feed production, good practice should be followed thoroughly at all levels of production, distribution

  11. Dissecting children's observational learning of complex actions through selective video displays.

    Science.gov (United States)

    Flynn, Emma; Whiten, Andrew

    2013-10-01

    Children can learn how to use complex objects by watching others, yet the relative importance of different elements they may observe, such as the interactions of the individual parts of the apparatus, a model's movements, and desirable outcomes, remains unclear. In total, 140 3-year-olds and 140 5-year-olds participated in a study where they observed a video showing tools being used to extract a reward item from a complex puzzle box. Conditions varied according to the elements that could be seen in the video: (a) the whole display, including the model's hands, the tools, and the box; (b) the tools and the box but not the model's hands; (c) the model's hands and the tools but not the box; (d) only the end state with the box opened; and (e) no demonstration. Children's later attempts at the task were coded to establish whether they imitated the hierarchically organized sequence of the model's actions, the action details, and/or the outcome. Children's successful retrieval of the reward from the box and the replication of hierarchical sequence information were reduced in all but the whole display condition. Only once children had attempted the task and witnessed a second demonstration did the display focused on the tools and box prove to be better for hierarchical sequence information than the display focused on the tools and hands only. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Dynamic, continuous multitasking training leads to task-specific improvements but does not transfer across action selection tasks

    Science.gov (United States)

    Bender, Angela D.; Filmer, Hannah L.; Naughtin, Claire K.; Dux, Paul E.

    2017-12-01

    The ability to perform multiple tasks concurrently is an ever-increasing requirement in our information-rich world. Despite this, multitasking typically compromises performance due to the processing limitations associated with cognitive control and decision-making. While intensive dual-task training is known to improve multitasking performance, only limited evidence suggests that training-related performance benefits can transfer to untrained tasks that share overlapping processes. In the real world, however, coordinating and selecting several responses within close temporal proximity will often occur in high-interference environments. Over the last decade, there have been notable reports that training on video action games that require dynamic multitasking in a demanding environment can lead to transfer effects on aspects of cognition such as attention and working memory. Here, we asked whether continuous and dynamic multitasking training extends benefits to tasks that are theoretically related to the trained tasks. To examine this issue, we asked a group of participants to train on a combined continuous visuomotor tracking task and a perceptual discrimination task for six sessions, while an active control group practiced the component tasks in isolation. A battery of tests measuring response selection, response inhibition, and spatial attention was administered before and immediately after training to investigate transfer. Multitasking training resulted in substantial, task-specific gains in dual-task ability, but there was no evidence that these benefits generalized to other action control tasks. The findings suggest that training on a combined visuomotor tracking and discrimination task results in task-specific benefits but provides no additional value for untrained action selection tasks.

  13. Action-Selection Perseveration in Young Children : Advances of a Dynamic Model

    NARCIS (Netherlands)

    Cox, R.F.A

    2008-01-01

    This study presents an empirical test and dynamic model of perseverative limb selection in children of 14-, 24-, and 36-months old (N = 66 in total). In the experiment children repeatedly grasped a spoon with a single hand. In 2 separate conditions, the spoon was presented either 4 times on their

  14. Effects of gamma irradiation of the {sup 60} Co on antimicrobial action of plant extracts of bark and leaves of Schinus terebinthifolius Raddi; Efeitos da radiacao gama do {sup 60} Co sobre a acao antimicrobiana de extratos vegetais de cascas e folhas de Schinus terebinthifolius Raddi

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Edvane Borges da; Santos, Gustavo Henrique Farias dos; Amaral, Ademir de Jesus [Universidade Federal da Pernambuco (GERAR/DEN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Estudos em Radioprotecao e Radioecologia; Lima, Jeniffer Maiza de Souza [Universidade Federal da Pernambuco (CAV/UFPE), Vitoria de Santo Antao, PE (Brazil); Xisto, Kesia; Araujo, Rosilma de Oliveira [Universidade Federal da Pernambuco (DA/UFPE), Recife, PE (Brazil). Dept. de Antibioticos

    2014-07-01

    This study aimed to evaluate the potential for antimicrobial activity in vitro of extracts of bark and leaves of S. terebinthifolius treated with {sup 60}Co gamma radiation. 5,0 doses were used; 7.5 and 10 kGy, being held non-irradiated controls. To determine the antimicrobial activity was applied to the disc diffusion technique to evaluate the diameter of the inhibition zones against Gram-positive bacteria, gram-negative bacteria, alcohol-acid-resistant and yeast. Antimicrobial activity was considered significant for halos ≥ 15 mm. The results indicate an intensification of antimicrobial action of bark extracts, the 5.0 kGy, against S. aureus. Was held the micro dilution in broth to determine the minimum inhibitory concentration (MIC) and Minimum Bactericidal Concentration (MBC) of peels extracts, compared to eight clinical isolates of S. aureus. The MBC values showed that ionizing radiation did not produce the increased of anti bacteriostatic action of S. terebinthifolius, but the results indicated that S. terebinthifolius bark extracts can be used as an antimicrobial agent and ionizing radiation as an important alternative in this conservation feature.

  15. Chemical Profiling and Evaluation of Antioxidant and Anti-Microbial Properties of Selected Commercial Essential Oils: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Ângelo Luís

    2017-06-01

    Full Text Available Background: The last decades have seen an increased awareness by the scientific community of the extent of resistance to conventional antibiotics, particularly with respect to the emerging multidrug-resistant pathogenic microbes. Additionally, natural antioxidants have received significant attention among food professionals and consumers because of their assumed safety and potential therapeutic value. The aim of this work was to assess the antioxidant activities of eight selected commercial essential oils (EOs, together with the evaluation of their antibacterial and anti-quorum sensing properties. Methods: The chemical profiling of the EOs was performed using gas chromatography-mass spectrometry (GC-MS analysis. The antioxidant properties of the EOs were evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH free radical scavenging assay and by β-carotene bleaching test. Disc diffusion assays were employed to evaluate the anti-bacterial and anti-quorum sensing activities of the EOs. Results: It was observed that EOs from three Eucalyptus species are rich in eucalyptol. Generally, linalool is abundant in EOs from four Lavandula species. The oil of Cymbopogon citratus is the one with the best capacity to scavenge the DPPH free radicals and presented great antibacterial activity. Conclusions: The geographical origins of the plant species are determinant factors in the EO composition and in the corresponding biological activities.

  16. Maximum entropy perception-action space: a Bayesian model of eye movement selection

    OpenAIRE

    Colas , Francis; Bessière , Pierre; Girard , Benoît

    2010-01-01

    International audience; In this article, we investigate the issue of the selection of eye movements in a free-eye Multiple Object Tracking task. We propose a Bayesian model of retinotopic maps with a complex logarithmic mapping. This model is structured in two parts: a representation of the visual scene, and a decision model based on the representation. We compare different decision models based on different features of the representation and we show that taking into account uncertainty helps...

  17. Mechanism of action and selective toxicity of ascamycin, a nucleoside antibiotic.

    OpenAIRE

    Osada, H; Isono, K

    1985-01-01

    An unidentified Streptomyces sp. produces two nucleoside antibiotics, ascamycin and its dealanyl derivative. In contrast to the broad antibacterial activity of dealanylascamycin against various gram-negative and gram-positive bacteria, ascamycin showed selective toxicity against Xanthomonas citri and X. oryzae. Both ascamycin and dealanylascamycin inhibited the protein synthesis of X. citri, but only dealanylascamycin inhibited that of Escherichia coli. In cell-free systems from E. coli and X...

  18. Human prosaccades and antisaccades under risk: effects of penalties and rewards on visual selection and the value of actions.

    Science.gov (United States)

    Ross, M; Lanyon, L J; Viswanathan, J; Manoach, D S; Barton, J J S

    2011-11-24

    Monkey studies report greater activity in the lateral intraparietal area and more efficient saccades when targets coincide with the location of prior reward cues, even when cue location does not indicate which responses will be rewarded. This suggests that reward can modulate spatial attention and visual selection independent of the "action value" of the motor response. Our goal was first to determine whether reward modulated visual selection similarly in humans, and next, to discover whether reward and penalty differed in effect, if cue effects were greater for cognitively demanding antisaccades, and if financial consequences that were contingent on stimulus location had spatially selective effects. We found that motivational cues reduced all latencies, more for reward than penalty. There was an "inhibition-of-return"-like effect at the location of the cue, but unlike the results in monkeys, cue valence did not modify this effect in prosaccades, and the inhibition-of-return effect was slightly increased rather than decreased in antisaccades. When financial consequences were contingent on target location, locations without reward or penalty consequences lost the benefits seen in noncontingent trials, whereas locations with consequences maintained their gains. We conclude that unlike monkeys, humans show reward effects not on visual selection but on the value of actions. The human saccadic system has both the capacity to enhance responses to multiple locations simultaneously, and the flexibility to focus motivational enhancement only on locations with financial consequences. Reward is more effective than penalty, and both interact with the additional attentional demands of the antisaccade task. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

  19. Toxicity, sublethal effects, and potential modes of action of select fungicides on freshwater fish and invertebrates

    Science.gov (United States)

    Elskus, Adria A.

    2012-01-01

    Despite decades of agricultural and urban use of fungicides and widespread detection of these pesticides in surface waters, relatively few data are available on the effects of fungicides on fish and invertebrates in the aquatic environment. Nine fungicides are reviewed in this report: azoxystrobin, boscalid, chlorothalonil, fludioxonil, myclobutanil, fenarimol, pyraclostrobin, pyrimethanil, and zoxamide. These fungicides were identified as emerging chemicals of concern because of their high or increasing global use rates, detection frequency in surface waters, or likely persistence in the environment. A review of the literature revealed significant sublethal effects of fungicides on fish, aquatic invertebrates, and ecosystems, including zooplankton and fish reproduction, fish immune function, zooplankton community composition, metabolic enzymes, and ecosystem processes, such as leaf decomposition in streams, among other biological effects. Some of these effects can occur at fungicide concentrations well below single-species acute lethality values (48- or 96-hour concentration that effects a response in 50 percent of the organisms, that is, effective concentration killing 50 percent of the organisms in 48 or 96 hours) and chronic sublethal values (for example, 21-day no observed adverse effects concentration), indicating that single-species toxicity values may dramatically underestimate the toxic potency of some fungicides. Fungicide modes of toxic action in fungi can sometimes reflect the biochemical and (or) physiological effects of fungicides observed in vertebrates and invertebrates; however, far more studies are needed to explore the potential to predict effects in nontarget organisms based on specific fungicide modes of toxic action. Fungicides can also have additive and (or) synergistic effects when used with other fungicides and insecticides, highlighting the need to study pesticide mixtures that occur in surface waters. For fungicides that partition to

  20. The antimicrobial resistance containment and surveillance approach--a public health tool.

    Science.gov (United States)

    Simonsen, Gunnar S.; Tapsall, John W.; Allegranzi, Benedetta; Talbot, Elizabeth A.; Lazzari, Stefano

    2004-01-01

    Antimicrobial drug resistance (AMR) is widely recognized as a global public health threat because it endangers the effectiveness of treatment of infectious diseases. In 2001 WHO issued the Global Strategy for Containment of Antimicrobial Resistance, but it has proved difficult to translate the recommendations of the Global Strategy into effective public health actions. The purpose of the Antimicrobial Resistance Containment and Surveillance (ARCS) approach is to facilitate the formulation of public health programmes and the mobilization of human and financial resources for the containment of AMR. The ARCS approach highlights the fundamental link between rational drug use and containment of AMR. Clinical management of human and animal infections should be improved through better disease control and prevention, high quality diagnostic testing, appropriate treatment regimens and consumer health education. At the same time, systems for supplying antimicrobial drugs should include appropriate regulations, lists of essential drugs, and functional mechanisms for the approval and delivery of drugs. Containment of AMR is defined in the ARCS approach as the continuous application of this package of core interventions. Surveillance of the extent and trends of antimicrobial resistance as well as the supply, selection and use of antimicrobial drugs should be established to monitor the process and outcome of containment of AMR. The ARCS approach is represented in the ARCS diagram (Fig. 2) which provides a simplified, but comprehensive illustration of the complex problem of containment and monitoring of AMR. PMID:15654407

  1. Causal Inference for Cross-Modal Action Selection: A Computational Study in a Decision Making Framework.

    Science.gov (United States)

    Daemi, Mehdi; Harris, Laurence R; Crawford, J Douglas

    2016-01-01

    Animals try to make sense of sensory information from multiple modalities by categorizing them into perceptions of individual or multiple external objects or internal concepts. For example, the brain constructs sensory, spatial representations of the locations of visual and auditory stimuli in the visual and auditory cortices based on retinal and cochlear stimulations. Currently, it is not known how the brain compares the temporal and spatial features of these sensory representations to decide whether they originate from the same or separate sources in space. Here, we propose a computational model of how the brain might solve such a task. We reduce the visual and auditory information to time-varying, finite-dimensional signals. We introduce controlled, leaky integrators as working memory that retains the sensory information for the limited time-course of task implementation. We propose our model within an evidence-based, decision-making framework, where the alternative plan units are saliency maps of space. A spatiotemporal similarity measure, computed directly from the unimodal signals, is suggested as the criterion to infer common or separate causes. We provide simulations that (1) validate our model against behavioral, experimental results in tasks where the participants were asked to report common or separate causes for cross-modal stimuli presented with arbitrary spatial and temporal disparities. (2) Predict the behavior in novel experiments where stimuli have different combinations of spatial, temporal, and reliability features. (3) Illustrate the dynamics of the proposed internal system. These results confirm our spatiotemporal similarity measure as a viable criterion for causal inference, and our decision-making framework as a viable mechanism for target selection, which may be used by the brain in cross-modal situations. Further, we suggest that a similar approach can be extended to other cognitive problems where working memory is a limiting factor, such

  2. Skeletal unloading induces selective resistance to the anabolic actions of growth hormone on bone

    Science.gov (United States)

    Halloran, B. P.; Bikle, D. D.; Harris, J.; Autry, C. P.; Currier, P. A.; Tanner, S.; Patterson-Buckendahl, P.; Morey-Holton, E.

    1995-01-01

    Loss of skeletal weight bearing or physical unloading of bone in the growing animal inhibits bone formation and induces a bone mineral deficit. To determine whether the inhibition of bone formation induced by skeletal unloading in the growing animal is a consequence of diminished sensitivity to growth hormone (GH) we studied the effects of skeletal unloading in young hypophysectomized rats treated with GH (0, 50, 500 micrograms/100 g body weight/day). Skeletal unloading reduced serum osteocalcin, impaired uptake of 3H-proline into bone, decreased proximal tibial mass, and diminished periosteal bone formation at the tibiofibular junction. When compared with animals receiving excipient alone, GH administration increased bone mass in all animals. The responses in serum osteocalcin, uptake of 3H-proline and 45Ca into the proximal tibia, and proximal tibial mass in non-weight bearing animals were equal to those in weight bearing animals. The responses in trabecular bone volume in the proximal tibia and bone formation at the tibiofibular junction to GH, however, were reduced significantly by skeletal unloading. Bone unloading prevented completely the increase in metaphyseal trabecular bone normally induced by GH and severely dampened the stimulatory effect (158% vs. 313%, p anabolic actions of GH.

  3. The influence of particle size and AgNO3 concentration in the ionic exchange process on the fungicidal action of antimicrobial glass

    International Nuclear Information System (INIS)

    Mendes, E.; Piletti, R.; Barichello, T.; Oliveira, C.M.; Kniess, C.T.; Angioletto, E.; Riella, H.G.

    2012-01-01

    Antimicrobial materials have long been used as an effective means of reducing the risks posed to humans by fungi, bacteria and other microorganisms. These materials are essential in environments where cleanliness, comfort and hygiene are the predominate concerns. This work presents preliminary results for the development of a fungicidal vitreous material that is produced by the incorporation of a silver ionic specimen through ionic exchange reactions. Silver ions were incorporated into powdered glass via ionic exchange in an ionic medium containing silver species with different concentrations of AgNO 3 . The fungicidal efficiency of the samples was studied as a function of the AgNO 3 concentration and the particle size of the glass using the agar diffusion test for the microbiological analysis of the fungus species Candida albicans. The samples were examined by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The experimental results showed that the fungicidal effect was dependent on the AgNO 3 concentration in the ionic exchange medium but was not dependent on the particle size of the glass. - Highlights: ► The fungicidal powder glass presents high potential for application as polymeric additive and others application in the medical area. ► The fungicidal effect was dependent on AgNO3 concentration, but was not dependent on the particle size of the glass. ► The XRD results show that the ionic exchange process promotes the formation of silver crystalline phases with cubic cells.

  4. Selective mode of action of guanidine-containing non-peptides at human NPFF receptors.

    Science.gov (United States)

    Findeisen, Maria; Würker, Cäcilia; Rathmann, Daniel; Meier, René; Meiler, Jens; Olsson, Roger; Beck-Sickinger, Annette G

    2012-07-12

    The binding pocket of both NPFF receptors was investigated, focusing on subtype-selective behavior. By use of four nonpeptidic compounds and the peptide mimetics RF9 and BIBP3226, agonistic and antagonistic properties were characterized. A set of Ala receptor mutants was generated. The binding pocket was narrowed down to the upper part of transmembrane helices V, VI, VII and the extracellular loop 2. Positions 5.27 and 6.59 have been shown to have a strong impact on receptor activation and were suggested to form an acidic, negatively charged binding pocket in both NPFF receptor subtypes. Additionally, position 7.35 was identified to play an important role in functional selectivity. According to docking experiments, the aryl group of AC-216 interacts with position 7.35 in the NPFF(1) but not in the NPFF(2) receptor. These results provide distinct insights into the receptor specific binding pockets, which is necessary for the development of drugs to address the NPFF system.

  5. Report on Action Research: An Analysis of the Effects of Selected Instructional Strategies on Student Achievement at Terre Haute North Vigo High School

    Science.gov (United States)

    Haystead, Mark W.

    2010-01-01

    This report describes the findings of an analysis of a series of action research projects conducted by Vigo County School Corporation at Terre Haute North Vigo High School. During the 2009-2010 school year, 17 teachers participated in independent action research studies regarding the extent to which selected instructional strategies enhanced the…

  6. Human Antimicrobial Peptides and Proteins

    Directory of Open Access Journals (Sweden)

    Guangshun Wang

    2014-05-01

    Full Text Available As the key components of innate immunity, human host defense antimicrobial peptides and proteins (AMPs play a critical role in warding off invading microbial pathogens. In addition, AMPs can possess other biological functions such as apoptosis, wound healing, and immune modulation. This article provides an overview on the identification, activity, 3D structure, and mechanism of action of human AMPs selected from the antimicrobial peptide database. Over 100 such peptides have been identified from a variety of tissues and epithelial surfaces, including skin, eyes, ears, mouths, gut, immune, nervous and urinary systems. These peptides vary from 10 to 150 amino acids with a net charge between −3 and +20 and a hydrophobic content below 60%. The sequence diversity enables human AMPs to adopt various 3D structures and to attack pathogens by different mechanisms. While α-defensin HD-6 can self-assemble on the bacterial surface into nanonets to entangle bacteria, both HNP-1 and β-defensin hBD-3 are able to block cell wall biosynthesis by binding to lipid II. Lysozyme is well-characterized to cleave bacterial cell wall polysaccharides but can also kill bacteria by a non-catalytic mechanism. The two hydrophobic domains in the long amphipathic α-helix of human cathelicidin LL-37 lays the basis for binding and disrupting the curved anionic bacterial membrane surfaces by forming pores or via the carpet model. Furthermore, dermcidin may serve as ion channel by forming a long helix-bundle structure. In addition, the C-type lectin RegIIIα can initially recognize bacterial peptidoglycans followed by pore formation in the membrane. Finally, histatin 5 and GAPDH(2-32 can enter microbial cells to exert their effects. It appears that granulysin enters cells and kills intracellular pathogens with the aid of pore-forming perforin. This arsenal of human defense proteins not only keeps us healthy but also inspires the development of a new generation of personalized

  7. The prefrontal cortex shows context-specific changes in effective connectivity to motor or visual cortex during the selection of action or colour

    DEFF Research Database (Denmark)

    Rowe, James B.; Stephan, Klaas E.; Friston, Karl

    2005-01-01

    The role of the prefrontal cortex remains controversial. Neuroimaging studies support modality-specific and process-specific functions related to working memory and attention. Its role may also be defined by changes in its influence over other brain regions including sensory and motor cortex. We...... used functional magnetic imaging (fMRI) to study the free selection of actions and colours. Control conditions used externally specified actions and colours. The prefrontal cortex was activated during free selection, regardless of modality, in contrast to modality-specific activations outside...... included high-order interactions between modality, selection and regional activity. There was greater coupling between prefrontal cortex and motor cortex during free selection and action tasks, and between prefrontal cortex and visual cortex during free selection of colours. The results suggest...

  8. Associations between Antimicrobial Resistance Phenotypes, Antimicrobial Resistance Genes, and Virulence Genes of Fecal Escherichia coli Isolates from Healthy Grow-Finish Pigs ▿

    OpenAIRE

    Rosengren, Leigh B.; Waldner, Cheryl L.; Reid-Smith, Richard J.

    2009-01-01

    Escherichia coli often carries linked antimicrobial resistance genes on transmissible genetic elements. Through coselection, antimicrobial use may select for unrelated but linked resistance or virulence genes. This study used unconditional statistical associations to investigate the relationships between antimicrobial resistance phenotypes and antimicrobial resistance genes in 151 E. coli isolates from healthy pigs. Phenotypic resistance to each drug was significantly associated with phenotyp...

  9. Prior Cocaine Self-Administration Increases Response-Outcome Encoding That Is Divorced from Actions Selected in Dorsal Lateral Striatum.

    Science.gov (United States)

    Burton, Amanda C; Bissonette, Gregory B; Zhao, Adam C; Patel, Pooja K; Roesch, Matthew R

    2017-08-09

    Dorsal lateral striatum (DLS) is a highly associative structure that encodes relationships among environmental stimuli, behavioral responses, and predicted outcomes. DLS is known to be disrupted after chronic drug abuse; however, it remains unclear what neural signals in DLS are altered. Current theory suggests that drug use enhances stimulus-response processing at the expense of response-outcome encoding, but this has mostly been tested in simple behavioral tasks. Here, we investigated what neural correlates in DLS are affected by previous cocaine exposure as rats performed a complex reward-guided decision-making task in which predicted reward value was independently manipulated by changing the delay to or size of reward associated with a response direction across a series of trial blocks. After cocaine self-administration, rats exhibited stronger biases toward higher-value reward and firing in DLS more strongly represented action-outcome contingencies independent from actions subsequently taken rather than outcomes predicted by selected actions (chosen-outcome contingencies) and associations between stimuli and actions (stimulus-response contingencies). These results suggest that cocaine self-administration strengthens action-outcome encoding in rats (as opposed to chosen-outcome or stimulus-response encoding), which abnormally biases behavior toward valued reward when there is a choice between two options during reward-guided decision-making. SIGNIFICANCE STATEMENT Current theories suggest that the impaired decision-making observed in individuals who chronically abuse drugs reflects a decrease in goal-directed behaviors and an increase in habitual behaviors governed by neural representations of response-outcome (R-O) and stimulus-response associations, respectively. We examined the impact that prior cocaine self-administration had on firing in dorsal lateral striatum (DLS), a brain area known to be involved in habit formation and affected by drugs of abuse

  10. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing options ... CVM) produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, ...

  11. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing options ... produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, ...

  12. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing ... CVM) produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over ...

  13. Cyclodextrins: A Weapon in the Fight Against Antimicrobial Resistance

    Science.gov (United States)

    Wong, Chew Ee; Dolzhenko, Anton V.; Lee, Sui Mae; Young, David James

    Antimicrobial resistance poses one of the most serious global challenges of our age. Cyclodextrins (CDs) are widely utilized excipients in formulations because of their solubilizing properties, low toxicity, and low inflammatory response. This review summarizes recent investigations of antimicrobial agents involving CDs and CD-based antimicrobial materials. CDs have been employed for antimicrobial applications either through formation of inclusion complexes or by chemical modification of their hydroxyl groups to tailor pharmaceutically active compounds. Applications of these CD inclusion complexes include drug delivery, antimicrobial coatings on materials (e.g., biomedical devices and implants) and antimicrobial dressings that help to prevent wound infections. There are relatively limited studies of chemically modified CDs with antimicrobial activity. The mechanism of action of antimicrobial CD inclusion complexes and derivatives needs further elucidation, but activity of CDs and their derivatives is often associated with their interaction with bacterial cell membranes.

  14. A successful effort to involve stakeholders in the selection of a site for a corrective action management unit

    International Nuclear Information System (INIS)

    Conway, R.; Merkhofer, M.W.; Oms, E.

    1995-01-01

    As part of the effort to clean up hazardous waste sites, Sandia National Laboratories in New Mexico (SNL/NM) adopted a novel approach to involving stakeholders in a key decision associated with its Environmental Restoration (ER) Project. The decision was where to locate a Corrective Action Management Unit (CAMU), an area designed to consolidate, store, and treat wastes generated from cleanup activities. The decision-making approach was a variation of a technique known as multiattribute utility analysis (MUA). Although MUA has rarely been undertaken during normal Project activities, it proved to be a surprisingly effective means for involving stakeholders in the decision process, generating consensus over a selected site, and enhancing public trust and understanding of Project activities. Requirements and criteria for selecting CAMU sites are provided by the Environmental Protection Agency's (EPA's) CAMU Final Rule (EPA 1993). Recognizing the lack of experience with the Rule and the importance of community understanding and support, the ER Project sought an approach that would allow stakeholders to participate in the site-selection process

  15. Development of a computer code system for selecting off-site protective action in radiological accidents based on the multiobjective optimization method

    International Nuclear Information System (INIS)

    Ishigami, Tsutomu; Oyama, Kazuo

    1989-09-01

    This report presents a new method to support selection of off-site protective action in nuclear reactor accidents, and provides a user's manual of a computer code system, PRASMA, developed using the method. The PRASMA code system gives several candidates of protective action zones of evacuation, sheltering and no action based on the multiobjective optimization method, which requires objective functions and decision variables. We have assigned population risks of fatality, injury and cost as the objective functions, and distance from a nuclear power plant characterizing the above three protective action zones as the decision variables. (author)

  16. Production of Antimicrobial Agent by Streptomyces violachromogenes

    International Nuclear Information System (INIS)

    Ahmed, Arwa A.

    2007-01-01

    The isolation of antibiotics from microorganisms improved the discovery of novel antibiotics, which is relatively easy as compared to chemical synthesis of antimicrobial agents. This study starts from isolation and purification of the antimicrobial producing Sterptomycetes obtained from soil habitat of Yemen. The good antimicrobial producing Sterptomycetes isolate was selected from a batch of Sterptomycetes isolates then identified. This isolate has bioactivity against some G+ve and G-ve bacteria. The antimicrobial agent isolated from Streptomyces violachromogenes (isolate no.YA118) was extracted with ethyl acetate at pH 3. The residue was applied to a silica gel column chromatography and eluted stepwise with many solvent systems. The active fractions were tested with B. subtilis NCTC10400. The purification of the antibiotic has been carried out by thin layer chromatography then the physical and chemical properties were studied to identify the antimicrobial agent. The isolated antimicrobial agent is an antibiotic belonging to the neomycin group. (author)

  17. Use of antimicrobial agents in aquaculture.

    Science.gov (United States)

    Park, Y H; Hwang, S Y; Hong, M K; Kwon, K H

    2012-04-01

    The aquaculture industry has grown dramatically, and plays an important role in the world's food supply chain. Antimicrobial resistance in bacteria associated with food animals receives much attention, and drug use in aquaculture is also an important issue. There are many differences between aquatic and terrestrial management systems, such as the methods used for administration of drugs. Unique problems are related to the application of drugs in aquatic environments. Residual drugs in fish products can affect people who consume them, and antimicrobials released into aquatic environments can select for resistant bacteria. Moreover, these antimicrobial-resistant bacteria, or their resistance genes, can be transferred to humans. To decrease the risks associated with the use of antimicrobials, various regulations have been developed. In addition, it is necessary to prevent bacterial diseases in aquatic animals by vaccination, to improve culture systems, and to monitor the amount of antimicrobial drugs used and the prevalence of antimicrobial-resistant bacteria.

  18. Dipeptidyl peptidase IV as a potential target for selective prodrug activation and chemotherapeutic action in cancers.

    Science.gov (United States)

    Dahan, Arik; Wolk, Omri; Yang, Peihua; Mittal, Sachin; Wu, Zhiqian; Landowski, Christopher P; Amidon, Gordon L

    2014-12-01

    The efficacy of chemotherapeutic drugs is often offset by severe side effects attributable to poor selectivity and toxicity to normal cells. Recently, the enzyme dipeptidyl peptidase IV (DPPIV) was considered as a potential target for the delivery of chemotherapeutic drugs. The purpose of this study was to investigate the feasibility of targeting chemotherapeutic drugs to DPPIV as a strategy to enhance their specificity. The expression profile of DPPIV was obtained for seven cancer cell lines using DNA microarray data from the DTP database, and was validated by RT-PCR. A prodrug was then synthesized by linking the cytotoxic drug melphalan to a proline-glycine dipeptide moiety, followed by hydrolysis studies in the seven cell lines with a standard substrate, as well as the glycyl-prolyl-melphalan (GP-Mel). Lastly, cell proliferation studies were carried out to demonstrate enzyme-dependent activation of the candidate prodrug. The relative RT-PCR expression levels of DPPIV in the cancer cell lines exhibited linear correlation with U95Av2 Affymetrix data (r(2) = 0.94), and with specific activity of a standard substrate, glycine-proline-p-nitroanilide (r(2) = 0.96). The significantly higher antiproliferative activity of GP-Mel in Caco-2 cells (GI₅₀ = 261 μM) compared to that in SK-MEL-5 cells (GI₅₀ = 807 μM) was consistent with the 9-fold higher specific activity of the prodrug in Caco-2 cells (5.14 pmol/min/μg protein) compared to SK-MEL-5 cells (0.68 pmol/min/μg protein) and with DPPIV expression levels in these cells. Our results demonstrate the great potential to exploit DPPIV as a prodrug activating enzyme for efficient chemotherapeutic drug targeting.

  19. Improving regulatory effectiveness in Federal/State siting actions: Federal/State regulatory permitting actions in selected nuclear power station licensing cases

    International Nuclear Information System (INIS)

    Baroff, J.

    1977-06-01

    The Federal/State regulatory permitting actions in 12 case histories of nuclear power station licensing in nine different states are documented. General observations regarding Federal/State siting roles in the siting process are included. Eleven of the case histories are illustrated with a logic network that gives the actions of the utilities in addition to the Federal/State permits

  20. LL-37-derived short antimicrobial peptide KR-12-a5 and its d-amino acid substituted analogs with cell selectivity, anti-biofilm activity, synergistic effect with conventional antibiotics, and anti-inflammatory activity.

    Science.gov (United States)

    Kim, Eun Young; Rajasekaran, Ganesan; Shin, Song Yub

    2017-08-18

    KR-12-a5 is a 12-meric α-helical antimicrobial peptide (AMP) with dual antimicrobial and anti-inflammatory activities designed from human cathelicidin LL-37. We designed and synthesized a series of d-amino acid-substituted analogs of KR-12-a5 with the aim of developing novel α-helical AMPs that possess higher cell selectivity than KR-12-a5, while maintaining the anti-inflammatory activity. d-amino acid incorporation into KR-12-a5 induced a significant improvement in the cell selectivity by 2.6- to 13.6-fold as compared to KR-12-a5, while maintaining the anti-inflammatory activity. Among the three analogs, KR-12-a5 (6- D L) with d-amino acid in the polar-nonpolar interface (Leu 6 ) showed the highest cell selectivity (therapeutic index: 61.2). Similar to LL-37, KR-12-a5 and its analogs significantly inhibited the expression and secretion of NO, TNF-α, IL-6 and MCP-1 from LPS-stimulated RAW264.7 cells. KR-12-a5 and its analogs showed a more potent antimicrobial activity against antibiotic-resistant bacteria, including clinically isolated MRSA, MDRPA, and VREF than LL-37 and melittin. Furthermore, compared to LL-37, KR-12-a5 and its analogs showed greater synergistic effects with conventional antibiotics, such as chloramphenicol, ciprofloxacin, and oxacillin against MDRPA; KR-12-a5 and its analogs had a FICI range between 0.25 and 0.5, and LL-37 had a range between 0.75 and 1.5. KR-12-a5 and its analogs were found to be more effective anti-biofilm agents against MDRPA than LL-37. In addition, KR-12-a5 and its analogs maintained antimicrobial activity in physiological salts and human serum. SYTOX Green uptake and membrane depolarization studies revealed that KR-12-a5 and its analogs kills microbial cells by permeabilizing the cell membrane and damaging membrane integrity. Taken together, our results suggest that KR-12-a5 and its analogs can be developed further as novel antimicrobial/anti-inflammatory agents to treat antibiotic-resistant infections. Copyright

  1. Antimicrobial activity against Porphyromonas gingivalis and mechanism of action of the cationic octadecapeptide AmyI-1-18 and its amino acid-substituted analogs.

    Science.gov (United States)

    Taniguchi, Masayuki; Ochiai, Akihito; Takahashi, Kiyoshi; Nakamichi, Shun-Ichi; Nomoto, Takafumi; Saitoh, Eiichi; Kato, Tetsuo; Tanaka, Takaaki

    2016-12-01

    The antimicrobial peptide AmyI-1-18 is a cationic α-helical octadecapeptide derived from α-amylase in rice (Oryza sativa L. japonica) that contains four cationic amino acid residues (two arginines and two lysines). To enhance the antibacterial activity of AmyI-1-18 against Porphyromonas gingivalis (a bacterium associated with periodontal disease), we synthesized 12 analogs bearing substitutions with alanine, leucine, and/or arginine that were designed based on helical wheel projections and investigated their antibacterial properties. The antibacterial properties of four analogs bearing substitution of a single arginine or lysine with alanine were almost similar to those of AmyI-1-18, suggesting that the antibacterial properties depend on the presence of three cationic amino acid residues. Of three single arginine-substituted analogs, AmyI-1-18(G12R) exhibited an antibacterial activity 2.8-fold higher [50% growth-inhibitory concentration (IC 50 ): 4.6 μM] than that of AmyI-1-18 (IC 50 : 13 μM). Likewise, the antibacterial properties of two single leucine-substituted analogs were significantly enhanced; in particular, AmyI-1-18(N3L) exhibited an antibacterial activity (IC 50 : 2.5 μM) 5.2-fold higher than that of AmyI-1-18. The hemolytic activity of AmyI-1-18(N3L) against mammalian red blood cells was low (2% at 50 μM). A membrane-depolarization assay using a membrane potential-sensitive fluorescent dye revealed that, similar to AmyI-1-18, the antibacterial activity of AmyI-1-18(N3L) was not dependent on its membrane-disrupting activity. Our results demonstrate that the antibacterial properties of AmyI-1-18 against P. gingivalis are significantly improved, without a significant increase in hemolytic activity, by replacing asparagine with leucine at position 3. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  2. Animation of Antimicrobial Resistance

    Science.gov (United States)

    ... Animal & Veterinary Cosmetics Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin ...

  3. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Animal & Veterinary Cosmetics Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin ...

  4. Animation of Antimicrobial Resistance

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    Full Text Available ... More in Antimicrobial Resistance National Antimicrobial Resistance Monitoring System ... If you need help accessing information in different file formats, see Instructions for Downloading ...

  5. Low concentrations of metformin selectively inhibit CD133⁺ cell proliferation in pancreatic cancer and have anticancer action.

    Directory of Open Access Journals (Sweden)

    Shanmiao Gou

    Full Text Available Pancreatic cancer is the fourth leading cause of cancer related deaths in the United States. The prognosis remains dismal with little advance in treatment. Metformin is a drug widely used for the treatment of type II diabetes. Recent epidemiologic data revealed that oral administration of metformin is associated with a reduced risk of pancreatic cancer, suggesting its potential as a novel drug for this disease. Many studies have demonstrated the in vitro anticancer action of metformin, but the typically used concentrations were much higher than the in vivo plasma and tissue concentrations achieved with recommended therapeutic doses of metformin, and low concentrations of metformin had little effect on the proliferation of pancreatic cancer cells. We examined the effect of low concentrations of metformin on different subpopulations of pancreatic cancer cells and found that these selectively inhibited the proliferation of CD133⁺ but not CD24⁺CD44⁺ESA⁺ cells. We also examined the effect of low concentrations of metformin on cell invasion and in vivo tumor formation, demonstrating in vitro and in vivo anticancer action. Metformin was associated with a reduction of phospho-Erk and phospho-mTOR independent of Akt and AMPK phosphorylation. CD133⁺ pancreatic cancer cells are considered to be cancer stem cells that contribute to recurrence, metastasis and resistance to adjuvant therapies in pancreatic cancer. Our results provide a basis for combination of metformin with current therapies to improve the prognosis of this disease.

  6. Intracellular Diagnostics: Hunting for the Mode of Action of Redox-Modulating Selenium Compounds in Selected Model Systems

    Directory of Open Access Journals (Sweden)

    Dominika Mániková

    2014-08-01

    Full Text Available Redox-modulating compounds derived from natural sources, such as redox active secondary metabolites, are currently of considerable interest in the field of chemoprevention, drug and phytoprotectant development. Unfortunately, the exact and occasionally even selective activity of such products, and the underlying (bio-chemical causes thereof, are often only poorly understood. A combination of the nematode- and yeast-based assays provides a powerful platform to investigate a possible biological activity of a new compound and also to explore the “redox link” which may exist between its activity on the one side and its chemistry on the other. Here, we will demonstrate the usefulness of this platform for screening several selenium and tellurium compounds for their activity and action. We will also show how the nematode-based assay can be used to obtain information on compound uptake and distribution inside a multicellular organism, whilst the yeast-based system can be employed to explore possible intracellular mechanisms via chemogenetic screening and intracellular diagnostics. Whilst none of these simple and easy-to-use assays can ultimately substitute for in-depth studies in human cells and animals, these methods nonetheless provide a first glimpse on the possible biological activities of new compounds and offer direction for more complicated future investigations. They may also uncover some rather unpleasant biochemical actions of certain compounds, such as the ability of the trace element supplement selenite to induce DNA strand breaks.

  7. Low Concentrations of Metformin Selectively Inhibit CD133+ Cell Proliferation in Pancreatic Cancer and Have Anticancer Action

    Science.gov (United States)

    Li, Xiangsheng; Shi, Pengfei; Liu, Tao; Wang, Chunyou

    2013-01-01

    Pancreatic cancer is the fourth leading cause of cancer related deaths in the United States. The prognosis remains dismal with little advance in treatment. Metformin is a drug widely used for the treatment of type II diabetes. Recent epidemiologic data revealed that oral administration of metformin is associated with a reduced risk of pancreatic cancer, suggesting its potential as a novel drug for this disease. Many studies have demonstrated the in vitro anticancer action of metformin, but the typically used concentrations were much higher than the in vivo plasma and tissue concentrations achieved with recommended therapeutic doses of metformin, and low concentrations of metformin had little effect on the proliferation of pancreatic cancer cells. We examined the effect of low concentrations of metformin on different subpopulations of pancreatic cancer cells and found that these selectively inhibited the proliferation of CD133+ but not CD24+CD44+ESA+ cells. We also examined the effect of low concentrations of metformin on cell invasion and in vivo tumor formation, demonstrating in vitro and in vivo anticancer action. Metformin was associated with a reduction of phospho-Erk and phospho-mTOR independent of Akt and AMPK phosphorylation. CD133+ pancreatic cancer cells are considered to be cancer stem cells that contribute to recurrence, metastasis and resistance to adjuvant therapies in pancreatic cancer. Our results provide a basis for combination of metformin with current therapies to improve the prognosis of this disease. PMID:23667692

  8. Antimicrobial use in swine production and its effect on the swine gut microbiota and antimicrobial resistance.

    Science.gov (United States)

    Holman, Devin B; Chénier, Martin R

    2015-11-01

    Antimicrobials have been used in swine production at subtherapeutic levels since the early 1950s to increase feed efficiency and promote growth. In North America, a number of antimicrobials are available for use in swine. However, the continuous administration of subtherapeutic, low concentrations of antimicrobials to pigs also provides selective pressure for antimicrobial-resistant bacteria and resistance determinants. For this reason, subtherapeutic antimicrobial use in livestock remains a source of controversy and concern. The swine gut microbiota demonstrates a number of changes in response to antimicrobial administration depending on the dosage, duration of treatment, age of the pigs, and gut location that is sampled. Both culture-independent and -dependent studies have also shown that the swine gut microbiota contains a large number of antimicrobial resistance determinants even in the absence of antimicrobial exposure. Heavy metals, such as zinc and copper, which are often added at relatively high doses to swine feed, may also play a role in maintaining antimicrobial resistance and in the stability of the swine gut microbiota. This review focuses on the use of antimicrobials in swine production, with an emphasis on the North American regulatory context, and their effect on the swine gut microbiota and on antimicrobial resistance determinants in the gut microbiota.

  9. Selecting interventions to promote fruit and vegetable consumption: from policy to action, a planning framework case study in Western Australia.

    Science.gov (United States)

    Pollard, Christina M; Lewis, Janette M; Binns, Colin W

    2008-12-24

    The Department of Health in Western Australia identified access to, and daily consumption of recommended amounts of fruit and vegetables, as priority health determinants. The numerous factors that influence supply and consumption of fruit and vegetables indicated that a comprehensive approach would be required.A government and non-government sector steering group was set up to select priority interventions using the National Public Health Partnership's Framework for Implementing Public Health Strategies. This structured framework was used for developing strategies to improve fruit and vegetable consumption and supply, and to identify implementation priorities.After one year a desktop audit of progress on framework interventions was undertaken. The structured framework led to a plan for defined actions, partners, costs, and performance indicators for strategies to improve fruit and vegetable consumption and supply. Lead agency custodians for management of the selected interventions were identified.After one year there was significant progress in the implementation of a number of the high-ranking interventions. The exception was interventions that provide the infrastructure support such as research and development capacity, information systems. A structured framework and stakeholder participation assisted in developing a fruit and vegetable implementation strategy. Engagement and commitment of influential and diverse stakeholders is needed, not just for program support, but particularly in the areas of food and nutrition policy development and providing the infrastructure support required. Further work is required to develop performance outcomes and cost effectiveness measures for many of the strategies that have been proposed to address portfolio objectives.

  10. Bioprospecting for culturable actinobacteria with antimicrobial ...

    African Journals Online (AJOL)

    Strains of Fusarium sp. H24, Trichoderma harzianum H5 and Colletotrichum ... Antibiosis was indicated by visually observable growth inhibition of the ... Table 1: Antimicrobial activity of seven selected strains against fungi and bacterial strains.

  11. Antimicrobial peptides interact with peptidoglycan

    Science.gov (United States)

    Neelay, Om P.; Peterson, Christian A.; Snavely, Mary E.; Brown, Taylor C.; TecleMariam, Ariam F.; Campbell, Jennifer A.; Blake, Allison M.; Schneider, Sydney C.; Cremeens, Matthew E.

    2017-10-01

    Traditional therapeutics are losing effectiveness as bacterial resistance increases, and antimicrobial peptides (AMPs) can serve as an alternative source for antimicrobial agents. Their mode of action is commonly hypothesized to involve pore formation in the lipid membrane, thereby leading to cell death. However, bacterial cell walls are much more complex than just the lipid membrane. A large portion of the wall is comprised of peptidoglycan, yet we did not find any report of AMP-peptidoglycan interactions. Consequently, this work evaluated AMP-peptidoglycan and AMP-phospholipid (multilamellar vesicles) interactions through tryptophan fluorescence. Given that peptidoglycan is insoluble and vesicles are large particles, we took advantage of the unique properties of Trp-fluorescence to use one technique for two very different systems. Interestingly, melittin and cecropin A interacted with peptidoglycan to a degree similar to vancomycin, a positive control. Whether these AMP-peptidoglycan interactions relate to a killing mode of action requires further study.

  12. The potent antimicrobial properties of cell penetrating peptide-conjugated silver nanoparticles with excellent selectivity for gram-positive bacteria over erythrocytes.

    Science.gov (United States)

    Liu, Lihong; Yang, Jun; Xie, Jianping; Luo, Zhentao; Jiang, Jiang; Yang, Yi Yan; Liu, Shaomin

    2013-05-07

    Silver nanoparticles are of great interest for use as antimicrobial agents. Studies aimed at producing potent nano-silver biocides have focused on manipulation of particle size, shape, composition and surface charge. Here, we report the cell penetrating peptide catalyzed formation of antimicrobial silver nanoparticles in N,N-dimethylformamide. The novel nano-composite demonstrated a distinctly enhanced biocidal effect toward bacteria (gram-positive Bacillus subtilis, gram-negative Escherichia coli) and pathogenic yeast (Candida albicans), as compared to triangular and extremely small silver nanoparticles. In addition, a satisfactory biocompatibility was verified by a haemolysis test. Our results provide a paradigm in developing strategies that can maximize the silver nanoparticle application potentials while minimizing the toxic effects.

  13. Antimicrobial assay and genetic screening of selected freshwater Cyanobacteria and identification of a biomolecule dihydro-2H-pyran-2-one derivative.

    Science.gov (United States)

    Srivastava, A; Singh, V K; Patnaik, S; Tripathi, J; Singh, P; Nath, G; Asthana, R K

    2017-04-01

    Explorations of freshwater Cyanobacteria as antimicrobial (bacteria, fungi and methicillin-resistant Staphylococcus aureus (MRSA) strains) drug resource using bioassay, NRPS (non-ribosomal polypeptide synthetase) and PKS (polyketide synthase) genes, as well as in silico approach. We have bioassayed the extracts of Phormidium CCC727, Geitlerinema CCC728, Arthrospira CCC729, Leptolyngbya CCC732, Phormidium CCC730, Phormidium CCC731 against six pathogenic bacteria comprising Gram (+ve): S. aureus including seven clinical MRSA and Enterococcus faecalis, Gram (-ve): Escherichia coli, Salmonella Typhimurium, Klebsiella pneumoniae and Shigella boydii along with non-pathogenic Enterobacter aerogenes as well as fungal strains (Cryptococcus neoformans and Candida albicans, C. krusei, C. tropicalis and Aspergillus niger) exhibiting antimicrobial potential. The NRPS and PKS genes of the target strains were also amplified and sequenced. The putative protein structures were predicted using bioinformatics approach. PKS gene expression indicated β keto-acyl synthase as one of the important active domains in the biomolecules related to antitumour and antifungal group. The simultaneous identification of the biomolecule (dihydro-2H-pyran-2-one derivative) was also inferred spectroscopically. Freshwater Cyanobacteria are prolific producers of secondary metabolite(s) that may act as the antimicrobial drug resource in addition to their much explored marine counterpart. © 2016 The Society for Applied Microbiology.

  14. Effects of selective serotonin reuptake inhibitors on thought-action fusion, metacognitions, and thought suppression in obsessive-compulsive disorder.

    Science.gov (United States)

    Besiroglu, Lutfullah; Çetinkaya, Nuralay; Selvi, Yavuz; Atli, Abdullah

    2011-01-01

    We aimed to assess whether cognitive processes change over time in patients with obsessive-compulsive disorder (OCD) receiving selective serotonin reuptake inhibitors without cognitive behavioral therapy and to investigate the factors associated with probable cognitive changes. During the 16 weeks of the study, 55 patients who met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria for OCD received open-label treatment with sertraline (100-200 mg/d) or fluoxetine (40-80 mg/d) and were assessed using the Yale-Brown Obsessive-Compulsive Scale, Beck Depression Inventory (BDI), Thought-Action Fusion Scale (TAFS), Metacognitions Questionnaire (MCQ-30), and White Bear Suppression Inventory (WBSI). The Yale-Brown Obsessive-Compulsive Scale (P < .001), BDI (P < .001), TAFS morality (P < .005), MCQ-30 (P < .01), and WBSI (P < .005) scores at follow-up were significantly lower than baseline scores. When we excluded OCD patients with depressive disorder (n = 12), statistical significance in paired comparisons for MCQ and WBSI disappeared. Similarly, when OCD patients with religious obsessions (n = 16) were excluded, paired comparisons for MCQ and TAF morality were not statistically significant. Changes in BDI, TAFS morality, MCQ-30, and WBSI (P < .005) were significantly correlated with changes in severity of obsessions, but not that of compulsions. After controlling for the change in depression severity, significant correlations between changes in obsessive and cognitive scales did not continue to have statistical significance. The BDI changes (P < .05) significantly explained the changes in symptom severity in a linear regression model. Our findings suggest that selective serotonin reuptake inhibitors can change appraisals of obsessive intrusions via their effects on negative emotions. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Stimulant effects of adenosine antagonists on operant behavior: differential actions of selective A2A and A1 antagonists

    Science.gov (United States)

    Randall, Patrick A.; Nunes, Eric J.; Janniere, Simone L.; Stopper, Colin M.; Farrar, Andrew M.; Sager, Thomas N.; Baqi, Younis; Hockemeyer, Jörg; Müller, Christa E.

    2012-01-01

    Rationale Adenosine A2A antagonists can reverse many of the behavioral effects of dopamine antagonists, including actions on instrumental behavior. However, little is known about the effects of selective adenosine antagonists on operant behavior when these drugs are administered alone. Objective The present studies were undertaken to investigate the potential for rate-dependent stimulant effects of both selective and nonselective adenosine antagonists. Methods Six drugs were tested: two nonselective adenosine antagonists (caffeine and theophylline), two adenosine A1 antagonists (DPCPX and CPT), and two adenosine A2A antagonists (istradefylline (KW6002) and MSX-3). Two schedules of reinforcement were employed; a fixed interval 240-s (FI-240 sec) schedule was used to generate low baseline rates of responding and a fixed ratio 20 (FR20) schedule generated high rates. Results Caffeine and theophylline produced rate-dependent effects on lever pressing, increasing responding on the FI-240 sec schedule but decreasing responding on the FR20 schedule. The A2A antagonists MSX-3 and istradefylline increased FI-240 sec lever pressing but did not suppress FR20 lever pressing in the dose range tested. In fact, there was a tendency for istradefylline to increase FR20 responding at a moderate dose. A1 antagonists failed to increase lever pressing rate, but DPCPX decreased FR20 responding at higher doses. Conclusions These results suggest that adenosine A2A antagonists enhance operant response rates, but A1 antagonists do not. The involvement of adenosine A2A receptors in regulating aspects of instrumental response output and behavioral activation may have implications for the treatment of effort-related psychiatric dysfunctions, such as psychomotor slowing and anergia in depression. PMID:21347642

  16. The role of motor memory in action selection and procedural learning: insights from children with typical and atypical development

    Directory of Open Access Journals (Sweden)

    Jessica Tallet

    2015-07-01

    Full Text Available Motor memory is the process by which humans can adopt both persistent and flexible motor behaviours. Persistence and flexibility can be assessed through the examination of the cooperation/competition between new and old motor routines in the motor memory repertoire. Two paradigms seem to be particularly relevant to examine this competition/cooperation. First, a manual search task for hidden objects, namely the C-not-B task, which allows examining how a motor routine may influence the selection of action in toddlers. The second paradigm is procedural learning, and more precisely the consolidation stage, which allows assessing how a previously learnt motor routine becomes resistant to subsequent programming or learning of a new – competitive – motor routine. The present article defends the idea that results of both paradigms give precious information to understand the evolution of motor routines in healthy children. Moreover, these findings echo some clinical observations in developmental neuropsychology, particularly in children with Developmental Coordination Disorder. Such studies suggest that the level of equilibrium between persistence and flexibility of motor routines is an index of the maturity of the motor system.

  17. The role of motor memory in action selection and procedural learning: insights from children with typical and atypical development.

    Science.gov (United States)

    Tallet, Jessica; Albaret, Jean-Michel; Rivière, James

    2015-01-01

    Motor memory is the process by which humans can adopt both persistent and flexible motor behaviours. Persistence and flexibility can be assessed through the examination of the cooperation/competition between new and old motor routines in the motor memory repertoire. Two paradigms seem to be particularly relevant to examine this competition/cooperation. First, a manual search task for hidden objects, namely the C-not-B task, which allows examining how a motor routine may influence the selection of action in toddlers. The second paradigm is procedural learning, and more precisely the consolidation stage, which allows assessing how a previously learnt motor routine becomes resistant to subsequent programming or learning of a new - competitive - motor routine. The present article defends the idea that results of both paradigms give precious information to understand the evolution of motor routines in healthy children. Moreover, these findings echo some clinical observations in developmental neuropsychology, particularly in children with Developmental Coordination Disorder. Such studies suggest that the level of equilibrium between persistence and flexibility of motor routines is an index of the maturity of the motor system.

  18. Dopamine receptor blockade attenuates the general incentive motivational effects of noncontingently delivered rewards and reward-paired cues without affecting their ability to bias action selection.

    Science.gov (United States)

    Ostlund, Sean B; Maidment, Nigel T

    2012-01-01

    Environmental cues affect our behavior in a variety of ways. Despite playing an invaluable role in guiding our daily activities, such cues also appear to trigger the harmful, compulsive behaviors that characterize addiction and other disorders of behavioral control. In instrumental conditioning, rewards and reward-paired cues bias action selection and invigorate reward-seeking behaviors, and appear to do so through distinct neurobehavioral processes. Although reward-paired cues are known to invigorate performance through a dopamine-dependent incentive motivational process, it is not known if dopamine also mediates the influence of rewards and reward-paired cues over action selection. The current study contrasted the effects of systemic administration of the nonspecific dopamine receptor antagonist flupentixol on response invigoration and action bias in Pavlovian-instrumental transfer, a test of cue-elicited responding, and in instrumental reinstatement, a test of noncontingent reward-elicited responding. Hungry rats were trained on two different stimulus-outcome relationships (eg, tone-grain pellets and noise-sucrose solution) and two different action-outcome relationships (eg, left press-grain and right press-sucrose). At test, we found that flupentixol pretreatment blocked the response invigoration generated by the cues but spared their ability to bias action selection to favor the action whose outcome was signaled by the cue being presented. The response-biasing influence of noncontingent reward deliveries was also unaffected by flupentixol. Interestingly, although flupentixol had a modest effect on the immediate response invigoration produced by those rewards, it was particularly potent in countering the lingering enhancement of responding produced by multiple reward deliveries. These findings indicate that dopamine mediates the general incentive motivational effects of noncontingent rewards and reward-paired cues but does not support their ability to bias

  19. Remedial action plan and site design for stabilization of the inactive uranium mill tailings sites at Slick Rock, Colorado: Remedial Action Selection Report. Preliminary final

    Energy Technology Data Exchange (ETDEWEB)

    1994-03-01

    This proposed remedial action plan incorporates the results of detailed investigation of geologic, geomorphic, and seismic conditions at the proposed disposal site. The proposed remedial action will consist of relocating the uranium mill tailings, contaminated vicinity property materials, demolition debris, and windblown/waterborne materials to a permanent repository at the proposed Burro Canyon disposal cell. The proposed disposal site will be geomorphically stable. Seismic design parameters were developed for the geotechnical analyses of the proposed cell. Cell stability was analyzed to ensure long-term performance of the disposal cell in meeting design standards, including slope stability, settlement, and liquefaction potential. The proposed cell cover and erosion protection features were also analyzed and designed to protect the RRM (residual radioactive materials) against surface water and wind erosion. The location of the proposed cell precludes the need for permanent drainage or interceptor ditches. Rock to be used on the cell top-, side-, and toeslopes was sized to withstand probable maximum precipitation events.

  20. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Gunnison, Colorado: Remedial action selection report

    International Nuclear Information System (INIS)

    1992-10-01

    The Gunnison uranium mill tailings site is just south of the city limits of Gunnison, Colorado, in the south-central part of the state. The entire site covers 61 acres in the valley of the Gunnison River and Tomichi Creek. Contaminated materials at the Gunnison processing site include the tailings pile, covering about 35 acres to an average depth of nine feet and containing 459,000 cubic yards. Ore storage areas and the former mill processing area cover about 20 acres on the south side of the site. The volume of contaminated materials to be disposed of as part of the remedial action is estimated to be 718,900 cubic yards. An interim action was approved by the US Department of Energy to eliminate existing safety hazards to the Gunnison community. These actions, started in September 1991, included demolition of mill buildings and related processing facilities, excavation of two underground storage tanks, removal of asbestos and other hazardous materials from buildings, storage of those materials in a secured area on the site, and improvements of site security

  1. Antimicrobial use in Belgian broiler production.

    Science.gov (United States)

    Persoons, Davy; Dewulf, Jeroen; Smet, Annemieke; Herman, Lieve; Heyndrickx, Marc; Martel, An; Catry, Boudewijn; Butaye, Patrick; Haesebrouck, Freddy

    2012-08-01

    The use of antimicrobials in production animals has become a worldwide concern in the face of rising resistance levels in commensal, pathogenic and zoonotic bacteria. In the years 2007 and 2008 antimicrobial consumption records were collected during two non consecutive production cycles in 32 randomly selected Belgian broiler farms. Antimicrobials were used in 48 of the 64 monitored production cycles, 7 farms did not use any antimicrobials in both production cycles, 2 farms only administered antimicrobials in one of the two production cycles, the other 23 farms applied antimicrobial treatment in both production cycles. For the quantification of antimicrobial drug use, the treatment incidences (TI) based on the defined daily doses (the dose as it should be applied: DDD) and used daily doses (the actual dose applied: UDD) were calculated. A mean antimicrobial treatment incidence per 1000 animals of 131.8 (standard deviation 126.8) animals treated daily with one DDD and 121.4 (SD 106.7) animals treated daily with one UDD was found. The most frequently used compounds were amoxicillin, tylosin and trimethoprim-sulphonamide with a mean TI(UDD) of 37.9, 34.8, and 21.7, respectively. The ratio of the UDD/DDD gives an estimate on correctness of dosing. Tylosin was underdosed in most of the administrations whereas amoxicillin and trimethoprim-sulphonamide were slightly overdosed in the average flock. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Antimicrobial stewardship: Strategies for a global response

    Directory of Open Access Journals (Sweden)

    Jenny Grunwald

    2014-01-01

    Full Text Available The increasing antimicrobial resistance worldwide, combined with dwindling antimicrobial armamentarium, has resulted in a critical threat to the public health and safety of patients. To combat this hazard, antimicrobial stewardship programs (ASPs have emerged. Antimicrobial stewardship programs prevent or slow the emergence of antimicrobial resistance by coordinated interventions designed to optimize antimicrobial use to achieve the best clinical outcomes and limiting selective pressures that drive the emergence of resistance. This also reduces excessive costs attributable to suboptimal antimicrobial use. Even though an ideal effective ASP should incorporate more than one element simultaneously, it also requires a multidisciplinary team, which should include an infectious diseases physician, a clinical pharmacist with infectious diseases training, infection control professionals, hospital epidemiologist, a clinical microbiologist and an information specialist. However, for antimicrobial stewardship (AMS programs to be successful, they must address the specific needs of individual institutions, must be built on available resources, the limitations and advantages of each institution, and the available staffing and technological infrastructure.

  3. Cationic Antimicrobial Polymers and Their Assemblies

    Science.gov (United States)

    Carmona-Ribeiro, Ana Maria; de Melo Carrasco, Letícia Dias

    2013-01-01

    Cationic compounds are promising candidates for development of antimicrobial agents. Positive charges attached to surfaces, particles, polymers, peptides or bilayers have been used as antimicrobial agents by themselves or in sophisticated formulations. The main positively charged moieties in these natural or synthetic structures are quaternary ammonium groups, resulting in quaternary ammonium compounds (QACs). The advantage of amphiphilic cationic polymers when compared to small amphiphilic molecules is their enhanced microbicidal activity. Besides, many of these polymeric structures also show low toxicity to human cells; a major requirement for biomedical applications. Determination of the specific elements in polymers, which affect their antimicrobial activity, has been previously difficult due to broad molecular weight distributions and random sequences characteristic of radical polymerization. With the advances in polymerization control, selection of well defined polymers and structures are allowing greater insight into their structure-antimicrobial activity relationship. On the other hand, antimicrobial polymers grafted or self-assembled to inert or non inert vehicles can yield hybrid antimicrobial nanostructures or films, which can act as antimicrobials by themselves or deliver bioactive molecules for a variety of applications, such as wound dressing, photodynamic antimicrobial therapy, food packing and preservation and antifouling applications. PMID:23665898

  4. Cationic Antimicrobial Polymers and Their Assemblies

    Directory of Open Access Journals (Sweden)

    Ana Maria Carmona-Ribeiro

    2013-05-01

    Full Text Available Cationic compounds are promising candidates for development of antimicrobial agents. Positive charges attached to surfaces, particles, polymers, peptides or bilayers have been used as antimicrobial agents by themselves or in sophisticated formulations. The main positively charged moieties in these natural or synthetic structures are quaternary ammonium groups, resulting in quaternary ammonium compounds (QACs. The advantage of amphiphilic cationic polymers when compared to small amphiphilic molecules is their enhanced microbicidal activity. Besides, many of these polymeric structures also show low toxicity to human cells; a major requirement for biomedical applications. Determination of the specific elements in polymers, which affect their antimicrobial activity, has been previously difficult due to broad molecular weight distributions and random sequences characteristic of radical polymerization. With the advances in polymerization control, selection of well defined polymers and structures are allowing greater insight into their structure-antimicrobial activity relationship. On the other hand, antimicrobial polymers grafted or self-assembled to inert or non inert vehicles can yield hybrid antimicrobial nanostructures or films, which can act as antimicrobials by themselves or deliver bioactive molecules for a variety of applications, such as wound dressing, photodynamic antimicrobial therapy, food packing and preservation and antifouling applications.

  5. A Biologically Plausible Action Selection System for Cognitive Architectures: Implications of Basal Ganglia Anatomy for Learning and Decision-Making Models

    Science.gov (United States)

    Stocco, Andrea

    2018-01-01

    Several attempts have been made previously to provide a biological grounding for cognitive architectures by relating their components to the computations of specific brain circuits. Often, the architecture's action selection system is identified with the basal ganglia. However, this identification overlooks one of the most important features of…

  6. Antioxidant, antimicrobial and synergistic activities of tea polyphenols

    African Journals Online (AJOL)

    Microbial resistance to antibiotics has become an increasing global problem and there is a need to find out novel potent antimicrobial agents with alternative modes of action as accessories to antibiotic therapy. This study investigated the antioxidant, antimicrobial and synergistic properties of tea polyphenols. The tea ...

  7. Selectivity in the potentiation of antibacterial activity of α-peptide/β-peptoid peptidomimetics and antimicrobial peptides by human blood plasma

    DEFF Research Database (Denmark)

    Hein-Kristensen, Line; Knapp, Kolja M.; Franzyk, Henrik

    2013-01-01

    Antimicrobial peptides (AMPs) are promising leads for novel antibiotics; however, their activity is often compromised under physiological conditions. The purpose of this study was to determine the activity of alpha-peptide/beta-peptoid peptidomimetics and AMPs against Escherichia coli and Staphyl......Antimicrobial peptides (AMPs) are promising leads for novel antibiotics; however, their activity is often compromised under physiological conditions. The purpose of this study was to determine the activity of alpha-peptide/beta-peptoid peptidomimetics and AMPs against Escherichia coli...... and Staphylococcus aureus in the presence of human blood-derived matrices and immune effectors. The minimum inhibitory concentration (MIC) of two peptidomimetics against E. coli decreased by up to one order of magnitude when determined in 50% blood plasma as compared to MHB media. The MIC of a membrane-active AMP......, LL-I/3, also decreased, whereas two intracellularly acting AMPs were not potentiated by plasma. Blood serum had no effect on activity against E. coli and neither matrix had an effect on activity against S. aureus. Unexpectedly, physiological concentrations of human serum albumin did not influence...

  8. Comparative Evaluation of the Antimicrobial Activity of Different Antimicrobial Peptides against a Range of Pathogenic Bacteria

    DEFF Research Database (Denmark)

    Ebbensgaard, Anna Elisabeth; Mordhorst, Hanne; Overgaard, Michael Toft

    2015-01-01

    The rapid emergence of resistance to classical antibiotics has increased the interest in novel antimicrobial compounds. Antimicrobial peptides (AMPs) represent an attractive alternative to classical antibiotics and a number of different studies have reported antimicrobial activity data of various...... AMPs, but there is only limited comparative data available. The mode of action for many AMPs is largely unknown even though several models have suggested that the lipopolysaccharides (LPS) play a crucial role in the attraction and attachment of the AMP to the bacterial membrane in Gram...

  9. Antimicrobial Resistance of Faecal Escherichia coli Isolates from Pig Farms with Different Durations of In-feed Antimicrobial Use.

    Science.gov (United States)

    Gibbons, J F; Boland, F; Egan, J; Fanning, S; Markey, B K; Leonard, F C

    2016-05-01

    Antimicrobial use and resistance in animal and food production are of concern to public health. The primary aims of this study were to determine the frequency of resistance to 12 antimicrobials in Escherichia coli isolates from 39 pig farms and to identify patterns of antimicrobial use on these farms. Further aims were to determine whether a categorization of farms based on the duration of in-feed antimicrobial use (long-term versus short-term) could predict the occurrence of resistance on these farms and to identify the usage of specific antimicrobial drugs associated with the occurrence of resistance. Escherichia coli were isolated from all production stages on these farms; susceptibility testing was carried out against a panel of antimicrobials. Antimicrobial prescribing data were collected, and farms were categorized as long term or short term based on these. Resistance frequencies and antimicrobial use were tabulated. Logistic regression models of resistance to each antimicrobial were constructed with stage of production, duration of antimicrobial use and the use of 5 antimicrobial classes included as explanatory variables in each model. The greatest frequencies of resistance were observed to tetracycline, trimethoprim/sulphamethoxazole and streptomycin with the highest levels of resistance observed in isolates from first-stage weaned pigs. Differences in the types of antimicrobial drugs used were noted between long-term and short-term use farms. Categorization of farms as long- or short-term use was sufficient to predict the likely occurrence of resistance to 3 antimicrobial classes and could provide an aid in the control of resistance in the food chain. Stage of production was a significant predictor variable in all models of resistance constructed and did not solely reflect antimicrobial use at each stage. Cross-selection and co-selection for resistance was evident in the models constructed, and the use of trimethoprim/sulphonamide drugs in particular was

  10. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... search Popular ... produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will ...

  11. Antimicrobial Treatments and Efficacy

    Science.gov (United States)

    To limit exposure to indoor biological contamination a risk-management approach which employs various antimicrobial treatments can effectively control contaminants and reduce exposure. Antimicrobial treatment of biological contaminants, especially mold in buildings, it is often n...

  12. Antimicrobial (Drug) Resistance

    Science.gov (United States)

    ... with facebook share with twitter share with linkedin Antimicrobial (Drug) Resistance Go to Information for Researchers ► Credit: ... and infectious diseases. Why Is the Study of Antimicrobial (Drug) Resistance a Priority for NIAID? Over time, ...

  13. Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Mill Tailings Site, Maybell, Colorado. Remedial action selection report: Attachment 2, Geology report, Final

    International Nuclear Information System (INIS)

    1994-06-01

    The Maybell uranium mill tailings site is 25 miles (mi) (40 kilometers [km]) west of the town of Craig, Colorado, in Moffat County, in the northwestern part of the state. The unincorporated town of Maybell is 5 road mi (8 km) southwest of the site. The designated site covers approximately 110 acres (ac) (45 hectares [ha]) and consists of a concave-shaped tailings pile and rubble from the demolition of the mill buildings buried in the former mill area. Contaminated materials at the Maybell processing site include the tailings pile, which has an average depth of 20 feet (ft) (6 meters [m]) and contains 2.8 million cubic yards (yd 3 ) (2.1 million cubic meters [m 3 ]) of tailings. The former mill processing area is on the north side of the site and contains 20,000 yd 3 (15,000 m 3 ) of contaminated demolition debris. Off-pile contamination is present and includes areas adjacent to the tailings pile, as well as contamination dispersed by wind and surface water flow. The volume of off-pile contamination to be placed in the disposal cell is 550,000 yd 3 (420,000 m 3 ). The total volume of contaminated materials to be disposed of as part of the remedial action is estimated to be 3.37 million yd 3 (2.58 million m 3 ). Information presented in this Final Remedial Action Plan (RAP) and referenced in supporting documents represents the current disposal cell design features and ground water compliance strategy proposed by the US Department of Energy (DOE) for the Maybell, Colorado, tailings site. Both the disposal cell design and the ground water compliance strategy have changed from those proposed prior to the preliminary final RAP document as a result of prudent site-specific technical evaluations

  14. Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Mill Tailings Site, Maybell, Colorado. Remedial action selection report: Attachment 2, Geology report, Final

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    The Maybell uranium mill tailings site is 25 miles (mi) (40 kilometers [km]) west of the town of Craig, Colorado, in Moffat County, in the northwestern part of the state. The unincorporated town of Maybell is 5 road mi (8 km) southwest of the site. The designated site covers approximately 110 acres (ac) (45 hectares [ha]) and consists of a concave-shaped tailings pile and rubble from the demolition of the mill buildings buried in the former mill area. Contaminated materials at the Maybell processing site include the tailings pile, which has an average depth of 20 feet (ft) (6 meters [m]) and contains 2.8 million cubic yards (yd{sup 3}) (2.1 million cubic meters [m{sup 3}]) of tailings. The former mill processing area is on the north side of the site and contains 20,000 yd{sup 3} (15,000 m{sup 3}) of contaminated demolition debris. Off-pile contamination is present and includes areas adjacent to the tailings pile, as well as contamination dispersed by wind and surface water flow. The volume of off-pile contamination to be placed in the disposal cell is 550,000 yd{sup 3} (420,000 m{sup 3}). The total volume of contaminated materials to be disposed of as part of the remedial action is estimated to be 3.37 million yd{sup 3} (2.58 million m{sup 3}). Information presented in this Final Remedial Action Plan (RAP) and referenced in supporting documents represents the current disposal cell design features and ground water compliance strategy proposed by the US Department of Energy (DOE) for the Maybell, Colorado, tailings site. Both the disposal cell design and the ground water compliance strategy have changed from those proposed prior to the preliminary final RAP document as a result of prudent site-specific technical evaluations.

  15. Effect of substituting arginine and lysine with alanine on antimicrobial activity and the mechanism of action of a cationic dodecapeptide (CL(14-25)), a partial sequence of cyanate lyase from rice.

    Science.gov (United States)

    Taniguchi, Masayuki; Takahashi, Nobuteru; Takayanagi, Tomohiro; Ikeda, Atsuo; Ishiyama, Yohei; Saitoh, Eiichi; Kato, Tetsuo; Ochiai, Akihito; Tanaka, Takaaki

    2014-01-01

    The antimicrobial activity of analogs obtained by substituting arginine and lysine in CL(14-25), a cationic α-helical dodecapeptide, with alanine against Porphyromonas gingivalis, a periodontal pathogen, varied significantly depending on the number and position of cationic amino acids. The alanine-substituted analogs had no hemolytic activity, even at a concentration of 1 mM. The antimicrobial activities of CL(K20A) and CL(K20A, K25A) were 3.8-fold and 9.1-fold higher, respectively, than that of CL(14-25). The antimicrobial activity of CL(R15A) was slightly lower than that of CL(14-25), suggesting that arginine at position 15 is not essential but is important for the antimicrobial activity. The experiments in which the alanine-substituted analogs bearing the replacement of arginine at position 24 and/or lysine at position 25 were used showed that arginine at position 24 was crucial for the antimicrobial activity whenever lysine at position 25 was substituted with alanine. Helical wheel projections of the alanine-substituted analogs indicate that the hydrophobicity in the vicinity of leucine at position 16 and alanines at positions 18 and/or 21 increased by substituting lysine at positions 20 and 25 with alanine, respectively. The degrees of diSC3 -5 release from P. gingivalis cells and disruption of GUVs induced by the alanine-substituted analogs with different positive charges were not closely related to their antimicrobial activities. The enhanced antimicrobial activities of the alanine-substituted analogs appear to be mainly attributable to the changes in properties such as hydrophobicity and amphipathic propensity due to alanine substitution and not to their extents of positive charge (cationicity). Copyright © 2013 Wiley Periodicals, Inc.

  16. Processing and Integration of Contextual Information in Monkey Ventrolateral Prefrontal Neurons during Selection and Execution of Goal-Directed Manipulative Actions.

    Science.gov (United States)

    Bruni, Stefania; Giorgetti, Valentina; Bonini, Luca; Fogassi, Leonardo

    2015-08-26

    The prefrontal cortex (PFC) is deemed to underlie the complexity, flexibility, and goal-directedness of primates' behavior. Most neurophysiological studies performed so far investigated PFC functions with arm-reaching or oculomotor tasks, thus leaving unclear whether, and to which extent, PFC neurons also play a role in goal-directed manipulative actions, such as those commonly used by primates during most of their daily activities. Here we trained two macaques to perform or withhold grasp-to-eat and grasp-to-place actions, depending on the combination of two subsequently presented cues: an auditory go/no-go cue (high/low tone) and a visually presented target (food/object). By varying the order of presentation of the two cues, we could segment and independently evaluate the processing and integration of contextual information allowing the monkey to make a decision on whether or not to act, and what action to perform. We recorded 403 task-related neurons from the ventrolateral prefrontal cortex (VLPFC): unimodal sensory-driven (37%), motor-related (21%), unimodal sensory-and-motor (23%), and multisensory (19%) neurons. Target and go/no-go selectivity characterized most of the recorded neurons, particularly those endowed with motor-related discharge. Interestingly, multisensory neurons appeared to encode a behavioral decision independently from the sensory modality of the stimulus allowing the monkey to make it: some of them reflected the decision to act or refraining from acting (56%), whereas others (44%) encoded the decision to perform (or withhold) a specific action (e.g., grasp-to-eat). Our findings indicate that VLPFC neurons play a role in the processing of contextual information underlying motor decision during goal-directed manipulative actions. We demonstrated that macaque ventrolateral prefrontal cortex (VLPFC) neurons show remarkable selectivity for different aspects of the contextual information allowing the monkey to select and execute goal

  17. 'SOSORT consensus paper on brace action: TLSO biomechanics of correction (investigating the rationale for force vector selection'

    Directory of Open Access Journals (Sweden)

    Maruyama T

    2006-07-01

    Full Text Available Abstract Background The effectiveness of orthotic treatment continues to be controversial in international medical literature due to differences in the reported results and conclusions of various studies. Heterogeneity of the samples has been suggested as a reason for conflicting results. Besides the obvious theoretical differences between the brace concepts, the variability in the technical factors can also explain the contradictory results between same brace types. This paper will investigate the degree of variability among responses of scoliosis specialists from the Brace Study Ground of the International Society on Scoliosis Orthopedic and Rehabilitation Treatment SOSORT. Ultimately, this information could be a foundation for establishing a consensus and framework for future prospective controlled studies. Methods A preliminary questionnaire on the topic of 'brace action' relative to the theory of three-dimensional scoliosis correction and brace treatment was developed and circulated to specialists interested in the conservative treatment of adolescent idiopathic scoliosis. A particular case was presented (main thoracic curve with minor lumbar. Several key points emerged and were used to develop a second questionnaire which was discussed and full filed after the SOSORT consensus meeting (Milano, Italy, January 2005. Results Twenty-one questionnaires were completed. The Chêneau brace was the most frequently recommended. The importance of the three point system mechanism was stressed. Options about proper pad placement on the thoracic convexity were divided 50% for the pad reaching or involving the apical vertebra and 50% for the pad acting caudal to the apical vertebra. There was agreement about the direction of the vector force, 85% selecting a 'dorso lateral to ventro medial' direction but about the shape of the pad to produce such a force. Principles related to three-dimensional correction achieved high consensus (80%–85%, but suggested

  18. Chemical composition, antimicrobial and antioxidant activities of anethole-rich oil from leaves of selected varieties of fennel [Foeniculum vulgare Mill. ssp. vulgare var. azoricum (Mill.) Thell].

    Science.gov (United States)

    Senatore, Felice; Oliviero, Filomena; Scandolera, Elia; Taglialatela-Scafati, Orazio; Roscigno, Graziana; Zaccardelli, Massimo; De Falco, Enrica

    2013-10-01

    The chemical composition and biological activity of the essential oils obtained from the leaves of two different cultivars of Florence fennel cropped under three different fertilization treatments (Control not fertilized; Mineral Fertilization; Compost from Municipal Solid Wastes) have been analyzed. All the oils were characterized by high anethole concentration and some showed also a good percentage of limonene. Thus, the leaves of Florence fennel, which are agricultural wastes, could be used for the recovery of anethole to be used for its flavoring and biomedical properties. The antimicrobial activity expressed by assays on the examined oils indicates an appreciable effect, generally higher on Gram-positive bacteria. The various samples of Florence fennel analyzed did not show any results with FRAP test. The DPPH test showed a weak capacity of the samples to catch the free radicals from the solution, attributable to their content in anethole. © 2013.

  19. Nuclear facility decommissioning and site remedial actions: A selected bibliography, Volume 13: Part 2, Indexes. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Goins, L.F.; Webb, J.R.; Cravens, C.D.; Mallory, P.K.

    1992-09-01

    This is part 2 of a bibliography on nuclear facility decommissioning and site remedial action. This report contains indexes on the following: authors, corporate affiliation, title words, publication description, geographic location, subject category, and key word.

  20. Design and Engineering Strategies for Synthetic Antimicrobial Peptides

    Science.gov (United States)

    Tossi, Alessandro

    Thousands of antimicrobial peptides (AMPs) of prokaryotic, fungal, plant, or animal origin have been identified, and their potential as lead compounds for the design of novel therapeutic agents in the treatment of infection, for stimulating the immune system, or in countering septic shock has been widely recognized. Added to this is their possible use in prophylaxis of infectious diseases for animal or plant protection, for disinfection of surgical instruments or industrial surfaces, and for food preservation among other commercially important applications. Since the early eighties, AMPs have been subject to a vast number of studies aimed at understanding what determines their potency and spectrum of activities against bacterial or fungal pathogens, and at maximizing these while limiting cytotoxic activities toward host cells. Much research has also been directed toward understanding specific mechanisms of action underlying the antimicrobial activity and selectivity, to be able to redesign the peptides for optimal performance. A central theme in the mode of action of many AMPs is their dynamic interaction with biological membranes, which involves various properties of these peptides such as, among others, surface hydrophobicity and polarity, charge, structure, and induced conformational variations. These features are often intimately interconnected so that engineering peptides to independently adjust any one property in particular is not an easy task. However, solid-phase peptide synthesis allows the use of a large repertoire of nonproteinogenic amino acids that can be used in the rational design of peptides to finely tune structural and physicochemical properties and precisely probe structure-function relationships.

  1. Scottish Antimicrobial Prescribing Group (SAPG): development and impact of the Scottish National Antimicrobial Stewardship Programme.

    Science.gov (United States)

    Nathwani, Dilip; Sneddon, Jacqueline; Malcolm, William; Wiuff, Camilla; Patton, Andrea; Hurding, Simon; Eastaway, Anne; Seaton, R Andrew; Watson, Emma; Gillies, Elizabeth; Davey, Peter; Bennie, Marion

    2011-07-01

    In 2008, the Scottish Management of Antimicrobial Resistance Action Plan (ScotMARAP) was published by the Scottish Government. One of the key actions was initiation of the Scottish Antimicrobial Prescribing Group (SAPG), hosted within the Scottish Medicines Consortium, to take forward national implementation of the key recommendations of this action plan. The primary objective of SAPG is to co-ordinate and deliver a national framework or programme of work for antimicrobial stewardship. This programme, led by SAPG, is delivered by NHS National Services Scotland (Health Protection Scotland and Information Services Division), NHS Quality Improvement Scotland, and NHS National Education Scotland as well as NHS board Antimicrobial Management Teams. Between 2008 and 2010, SAPG has achieved a number of early successes, which are the subject of this review: (i) through measures to optimise prescribing in hospital and primary care, combined with infection prevention measures, SAPG has contributed significantly to reducing Clostridium difficile infection rates in Scotland; (ii) there has been engagement of all key stakeholders at local and national levels to ensure an integrated approach to antimicrobial stewardship within the wider healthcare-associated infection agenda; (iii) development and implementation of data management systems to support quality improvement; (iv) development of training materials on antimicrobial stewardship for healthcare professionals; and (v) improving clinical management of infections (e.g. community-acquired pneumonia) through quality improvement methodology. The early successes achieved by SAPG demonstrate that this delivery model is effective and provides the leadership and focus required to implement antimicrobial stewardship to improve antimicrobial prescribing and infection management across NHS Scotland. Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  2. Nanosilver: Potent antimicrobial agent and its biosynthesis

    African Journals Online (AJOL)

    VIKAS

    2014-01-22

    Jan 22, 2014 ... synthesis of silver nanoparticles, potential and the possible mechanism of antimicrobial actions. NANOSILVER SYNTHESIS- AN OVERVIEW. Nano silver are one of the promising products in the nanotechnology industry. The development of consistent processes for the synthesis of silver nanoparticles is an.

  3. The In Vitro Antimicrobial Effects of Lavandula angustifolia Essential Oil in Combination with Conventional Antimicrobial Agents

    Science.gov (United States)

    de Rapper, Stephanie; Viljoen, Alvaro

    2016-01-01

    The paper focuses on the in vitro antimicrobial activity of Lavandula angustifolia Mill. (lavender) essential oil in combination with four commercial antimicrobial agents. Stock solutions of chloramphenicol, ciprofloxacin, nystatin, and fusidic acid were tested in combination with L. angustifolia essential oil. The antimicrobial activities of the combinations were investigated against the Gram-positive bacterial strain Staphylococcus aureus (ATCC 6538) and Gram-negative Pseudomonas aeruginosa (ATCC 27858) and Candida albicans (ATCC 10231) was selected to represent the yeasts. The antimicrobial effect was performed using the minimum inhibitory concentration (MIC) microdilution assay. Isobolograms were constructed for varying ratios. The most prominent interaction was noted when L. angustifolia essential oil was combined with chloramphenicol and tested against the pathogen P. aeruginosa (ΣFIC of 0.29). Lavendula angustifolia essential oil was shown in most cases to interact synergistically with conventional antimicrobials when combined in ratios where higher volumes of L. angustifolia essential oil were incorporated into the combination. PMID:27891157

  4. The In Vitro Antimicrobial Effects of Lavandula angustifolia Essential Oil in Combination with Conventional Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Stephanie de Rapper

    2016-01-01

    Full Text Available The paper focuses on the in vitro antimicrobial activity of Lavandula angustifolia Mill. (lavender essential oil in combination with four commercial antimicrobial agents. Stock solutions of chloramphenicol, ciprofloxacin, nystatin, and fusidic acid were tested in combination with L. angustifolia essential oil. The antimicrobial activities of the combinations were investigated against the Gram-positive bacterial strain Staphylococcus aureus (ATCC 6538 and Gram-negative Pseudomonas aeruginosa (ATCC 27858 and Candida albicans (ATCC 10231 was selected to represent the yeasts. The antimicrobial effect was performed using the minimum inhibitory concentration (MIC microdilution assay. Isobolograms were constructed for varying ratios. The most prominent interaction was noted when L. angustifolia essential oil was combined with chloramphenicol and tested against the pathogen P. aeruginosa (ΣFIC of 0.29. Lavendula angustifolia essential oil was shown in most cases to interact synergistically with conventional antimicrobials when combined in ratios where higher volumes of L. angustifolia essential oil were incorporated into the combination.

  5. Antimicrobial stewardship: attempting to preserve a strategic resource

    Directory of Open Access Journals (Sweden)

    Trevor Van Schooneveld, Md

    2011-07-01

    Full Text Available Antimicrobials hold a unique place in our drug armamentarium. Unfortunately the increase in resistance among both gram-positive and gram-negative pathogens coupled with a lack of new antimicrobial agents is threatening our ability to treat infections. Antimicrobial use is the driving force behind this rise in resistance and much of this use is suboptimal. Antimicrobial stewardship programs (ASP have been advocated as a strategy to improve antimicrobial use. The goals of ASP are to improve patient outcomes while minimizing toxicity and selection for resistant strains by assisting in the selection of the correct agent, right dose, and best duration. Two major strategies for ASP exist: restriction/pre-authorization that controls use at the time of ordering and audit and feedback that reviews ordered antimicrobials and makes suggestions for improvement. Both strategies have some limitations, but have been effective at achieving stewardship goals. Other supplemental strategies such as education, clinical prediction rules, biomarkers, clinical decision support software, and institutional guidelines have been effective at improving antimicrobial use. The most effective antimicrobial stewardship programs have employed multiple strategies to impact antimicrobial use. Using these strategies stewardship programs have been able to decrease antimicrobial use, the spread of resistant pathogens, the incidence of C. difficile infection, pharmacy costs, and improved patient outcomes.

  6. Remedial action plan and site design for stabilization of the inactive uranium mill tailings site at Lowman, Idaho: Remedial action selection report for the Lowman UMTRA project site, Idaho

    International Nuclear Information System (INIS)

    Matthews, M.L.; Nagel, J.

    1991-09-01

    The inactive uranium mill tailings site near Lowman, Idaho, was designated as one of 24 abandoned uranium tailings sites to be remediated by the US Department of Energy (DOE) under the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA). The UMTRCA requires that the US Nuclear Regulatory Commission (NRC) concur with the DOE's remedial action plan and certify that the remedial action complies with the standards promulgated by the US Environmental Protection Agency (EPA). The remedial action plan (RAP), which includes this remedial action selection report (RAS), has been developed to serve a two-fold purpose. First, it describes the activities that are proposed by the DOE to accomplish long-term stabilization and control of residual radioactive materials at the inactive uranium processing site near Lowman, Idaho. Second, this document and the remainder of the RAP, upon concurrence and execution by the DOE, the State of Idaho, and the NRC, becomes Appendix B of the Cooperative Agreement (No. DE-FC04-85AL20535) between the DOE and the State of Idaho

  7. Nuclear facility decommissioning and site remedial actions: A selected bibliography, Volume 13: Part 1, Main text. Environmental Restoration Program

    Energy Technology Data Exchange (ETDEWEB)

    Goins, L.F.; Webb, J.R.; Cravens, C.D.; Mallory, P.K.

    1992-09-01

    This publication contains 1035 abstracted references on environmental restoration, nuclear facility decommissioning, uranium mill tailings management, and site remedial actions. These citations constitute the thirteenth in a series of reports prepared annually for the US Department of Energy (DOE) Environmental Restoration programs. Citations to foreign and domestic literature of all types. There are 13 major sections of the publication, including: (1) DOE Decontamination and Decommissioning Program; (2) Nuclear Facilities Decommissioning; (3) DOE Formerly Utilized Sites Remedial Action Program; (4) DOE Uranium Mill Tailings Remedial Action Project; (5) Uranium Mill Tailings Management; (6) DOE Environmental Restoration Program; (7) DOE Site-Specific Remedial Actions; (8) Contaminated Site Restoration; (9) Remediation of Contaminated Soil and Groundwater; (10) Environmental Data Measurements, Management, and Evaluation; (11) Remedial Action Assessment and Decision-Making; (12) Technology Development and Evaluation; and (13) Environmental and Waste Management Issues. Bibliographic references are arranged in nine subject categories by geographic location and then alphabetically by first author, corporate affiliation, or publication title. Indexes are provided for author, corporate affiliation, title word, publication description, geographic location, subject category, and key word.

  8. Current resistance issues in antimicrobial therapy | Senekal ...

    African Journals Online (AJOL)

    The human gut contains 1013 - 1014 bacteria that are exposed to selection pressure whenever antibiotics are administered.1 The same selection pressure applies to respiratory flora, which is one of the reasons why antimicrobial therapy prescribed for the treatment of respiratory tract infection should aim to eradicate ...

  9. Alternative Antimicrobial Approach: Nano-Antimicrobial Materials

    OpenAIRE

    Nurit Beyth; Yael Houri-Haddad; Avi Domb; Wahid Khan; Ronen Hazan

    2015-01-01

    Despite numerous existing potent antibiotics and other antimicrobial means, bacterial infections are still a major cause of morbidity and mortality. Moreover, the need to develop additional bactericidal means has significantly increased due to the growing concern regarding multidrug-resistant bacterial strains and biofilm associated infections. Consequently, attention has been especially devoted to new and emerging nanoparticle-based materials in the field of antimicrobial chemotherapy. The ...

  10. Antiproliferative and apoptotic effects of selective phenolic acids on T47D human breast cancer cells: potential mechanisms of action

    International Nuclear Information System (INIS)

    Kampa, Marilena; Boskou, Dimitrios; Gravanis, Achille; Castanas, Elias; Alexaki, Vassilia-Ismini; Notas, George; Nifli, Artemissia-Phoebe; Nistikaki, Anastassia; Hatzoglou, Anastassia; Bakogeorgou, Efstathia; Kouimtzoglou, Elena; Blekas, George

    2004-01-01

    The oncoprotective role of food-derived polyphenol antioxidants has been described but the implicated mechanisms are not yet clear. In addition to polyphenols, phenolic acids, found at high concentrations in a number of plants, possess antioxidant action. The main phenolic acids found in foods are derivatives of 4-hydroxybenzoic acid and 4-hydroxycinnamic acid. This work concentrates on the antiproliferative action of caffeic acid, syringic acid, sinapic acid, protocatechuic acid, ferulic acid and 3,4-dihydroxy-phenylacetic acid (PAA) on T47D human breast cancer cells, testing their antioxidant activity and a number of possible mechanisms involved (interaction with membrane and intracellular receptors, nitric oxide production). The tested compounds showed a time-dependent and dose-dependent inhibitory effect on cell growth with the following potency: caffeic acid > ferulic acid = protocatechuic acid = PAA > sinapic acid = syringic acid. Caffeic acid and PAA were chosen for further analysis. The antioxidative activity of these phenolic acids in T47D cells does not coincide with their inhibitory effect on tumoral proliferation. No interaction was found with steroid and adrenergic receptors. PAA induced an inhibition of nitric oxide synthase, while caffeic acid competes for binding and results in an inhibition of aryl hydrocarbon receptor-induced CYP1A1 enzyme. Both agents induce apoptosis via the Fas/FasL system. Phenolic acids exert a direct antiproliferative action, evident at low concentrations, comparable with those found in biological fluids after ingestion of foods rich in phenolic acids. Furthermore, the direct interaction with the aryl hydrocarbon receptor, the nitric oxide synthase inhibition and their pro-apoptotic effect provide some insights into their biological mode of action

  11. Review of decision methodologies for evaluating regulatory actions affecting public health and safety. [Nuclear industry site selection

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, P.L.; McDonald, C.L.; Schilling, A.H.

    1976-12-01

    This report examines several aspects of the problems and choices facing the governmental decision maker who must take regulatory actions with multiple decision objectives and attributes. Particular attention is given to the problems facing the U.S. Nuclear Regulatory Commission (NRC) and to the decision attribute of chief concern to NRC, the protection of human health and safety, with emphasis on nuclear power plants. The study was undertaken to provide background information for NRC to use in refining its process of value/impact assessment of proposed regulatory actions. The principal conclusion is that approaches to rationally consider the value and impact of proposed regulatory actions are available. These approaches can potentially improve the decision-making process and enable the agency to better explain and defend its decisions. They also permit consistent examination of the impacts, effects of uncertainty and sensitivity to various assumptions of the alternatives being considered. Finally, these approaches can help to assure that affected parties are heard and that technical information is used appropriately and to the extent possible. The principal aspects of the regulatory decision problem covered in the report are: the legal setting for regulatory decisions which affect human health and safety, elements of the decision-making process, conceptual approaches to decision making, current approaches to decision making in several Federal agencies, and the determination of acceptable risk levels.

  12. Oral antimicrobials increase antimicrobial resistance in porcine E. coli--a systematic review.

    Science.gov (United States)

    Burow, E; Simoneit, C; Tenhagen, B-A; Käsbohrer, A

    2014-03-01

    Administration of antimicrobials to livestock increases the risk of antimicrobial resistance (AMR) in commensal bacteria. Antimicrobials in pig production are usually administered per pen via feed which implies treatment of sick alongside with healthy animals. The objective of this systematic literature review was to investigate the effect of orally administered antimicrobials on AMR in Escherichia coli of swine. Studies published in peer reviewed journals were retrieved from the international online databases ISI Web of Knowledge, PubMed, Scopus and the national electronic literature data base of Deutsches Institut für Medizinische Dokumentation und Information. The studies were assessed using the eligibility criteria English or German language, access to full paper version, defined treatment and control group (initial value or non-treatment) as well as administration and resistance testing of the same antimicrobial class. In the qualitative synthesis, only studies were included presenting the summary measures odds ratio or prevalence of resistance, the category of the applied antimicrobial and the dosage. An effect of the antimicrobial on AMR in E. coli was evaluated as an "increase", "no effect" or "decrease" if the odds or alternatively the prevalence ratio were >1.0, 1.0 or antimicrobial substance and dosage was missing in 4 and 5 of the 11 finally selected studies. The 36 identified trials were inhomogenous in usage and provision of information on sample size. Oral administration of antimicrobials increases the risk of AMR in E. coli from swine. There is however a lack of studies on the impact of dosage and longitudinal effects of treatment. The published studies have a number of issues concerning their scientific quality. More high quality research is needed to better address and quantifiy the effect of orally administered antimicrobials on AMR in swine. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Salmon Aquaculture and Antimicrobial Resistance in the Marine Environment

    Science.gov (United States)

    Buschmann, Alejandro H.; Tomova, Alexandra; López, Alejandra; Maldonado, Miguel A.; Henríquez, Luis A.; Ivanova, Larisa; Moy, Fred; Godfrey, Henry P.; Cabello, Felipe C.

    2012-01-01

    Antimicrobials used in salmon aquaculture pass into the marine environment. This could have negative impacts on marine environmental biodiversity, and on terrestrial animal and human health as a result of selection for bacteria containing antimicrobial resistance genes. We therefore measured the numbers of culturable bacteria and antimicrobial-resistant bacteria in marine sediments in the Calbuco Archipelago, Chile, over 12-month period at a salmon aquaculture site approximately 20 m from a salmon farm and at a control site 8 km distant without observable aquaculture activities. Three antimicrobials extensively used in Chilean salmon aquaculture (oxytetracycline, oxolinic acid, and florfenicol) were studied. Although none of these antimicrobials was detected in sediments from either site, traces of flumequine, a fluoroquinolone antimicrobial also widely used in Chile, were present in sediments from both sites during this period. There were significant increases in bacterial numbers and antimicrobial-resistant fractions to oxytetracycline, oxolinic acid, and florfenicol in sediments from the aquaculture site compared to those from the control site. Interestingly, there were similar numbers of presumably plasmid-mediated resistance genes for oxytetracycline, oxolinic acid and florfenicol in unselected marine bacteria isolated from both aquaculture and control sites. These preliminary findings in one location may suggest that the current use of large amounts of antimicrobials in Chilean aquaculture has the potential to select for antimicrobial-resistant bacteria in marine sediments. PMID:22905164

  14. Antimicrobial peptides in the centipede Scolopendra subspinipes mutilans.

    Science.gov (United States)

    Yoo, Won Gi; Lee, Joon Ha; Shin, Younhee; Shim, Jae-Young; Jung, Myunghee; Kang, Byeong-Chul; Oh, Jaedon; Seong, Jiyeon; Lee, Hak Kyo; Kong, Hong Sik; Song, Ki-Duk; Yun, Eun-Young; Kim, In-Woo; Kwon, Young-Nam; Lee, Dong Gun; Hwang, Ui-Wook; Park, Junhyung; Hwang, Jae Sam

    2014-06-01

    The centipede Scolopendra subspinipes mutilans is an environmentally beneficial and medically important arthropod species. Although this species is increasingly applied as a reliable source of new antimicrobial peptides, the transcriptome of this species is a prerequisite for more rational selection of antimicrobial peptides. In this report, we isolated total RNA from the whole body of adult centipedes, S. subspinipes mutilans, that were nonimmunized and immunized against Escherichia coli, and we generated a total of 77,063 pooled contigs and singletons using high-throughput sequencing. To screen putative antimicrobial peptides, in silico analyses of the S. subspinipes mutilans transcriptome were performed based on the physicochemical evidence of length, charge, isoelectric point, and in vitro and in vivo aggregation scores together with the existence of continuous antimicrobial peptide stretches. Moreover, we excluded some transcripts that showed similarity with both previously known antimicrobial peptides and the human proteome, had a proteolytic cleavage site, and had downregulated expression compared with the nonimmunized sample. As a result, we selected 17 transcripts and tested their antimicrobial activity with a radial diffusion assay. Among them, ten synthetic peptides experimentally showed antimicrobial activity against microbes and no toxicity to mouse erythrocytes. Our results provide not only a useful set of antimicrobial peptide candidates and an efficient strategy for novel antimicrobial peptide development but also the transcriptome data of a big centipede as a valuable resource.

  15. Salmon aquaculture and antimicrobial resistance in the marine environment.

    Directory of Open Access Journals (Sweden)

    Alejandro H Buschmann

    Full Text Available Antimicrobials used in salmon aquaculture pass into the marine environment. This could have negative impacts on marine environmental biodiversity, and on terrestrial animal and human health as a result of selection for bacteria containing antimicrobial resistance genes. We therefore measured the numbers of culturable bacteria and antimicrobial-resistant bacteria in marine sediments in the Calbuco Archipelago, Chile, over 12-month period at a salmon aquaculture site approximately 20 m from a salmon farm and at a control site 8 km distant without observable aquaculture activities. Three antimicrobials extensively used in Chilean salmon aquaculture (oxytetracycline, oxolinic acid, and florfenicol were studied. Although none of these antimicrobials was detected in sediments from either site, traces of flumequine, a fluoroquinolone antimicrobial also widely used in Chile, were present in sediments from both sites during this period. There were significant increases in bacterial numbers and antimicrobial-resistant fractions to oxytetracycline, oxolinic acid, and florfenicol in sediments from the aquaculture site compared to those from the control site. Interestingly, there were similar numbers of presumably plasmid-mediated resistance genes for oxytetracycline, oxolinic acid and florfenicol in unselected marine bacteria isolated from both aquaculture and control sites. These preliminary findings in one location may suggest that the current use of large amounts of antimicrobials in Chilean aquaculture has the potential to select for antimicrobial-resistant bacteria in marine sediments.

  16. Reduction of veterinary antimicrobial use in the Netherlands. The Dutch success model

    NARCIS (Netherlands)

    Speksnijder, D.; Mevius, D.J.; Bruschke, C.J.M.; Wagenaar, J.A.

    2015-01-01

    Use of antimicrobials in animals poses a potential risk for public health as it contributes to the selection and spread of antimicrobial resistance. Although knowledge of the negative consequences of extensive antimicrobial use in humans and animals accumulated over the decades, total therapeutic

  17. Isolation and antimicrobial drug susceptibility pattern of bacterial pathogens from pediatric patients with otitis media in selected health institutions, Addis Ababa, Ethiopia: a prospective cross-sectional study.

    Science.gov (United States)

    Hailegiyorgis, Tewodros Tesfa; Sarhie, Wondemagegn Demsiss; Workie, Hailemariam Mekonnen

    2018-01-01

    Otitis media is inflammation of the middle ear and tympanic membrane, which often occurs after an acute upper respiratory tract infection. It is the most common episode of infection in children and the second most important cause of hearing loss affecting 1.23 billion people, thus ranked fifth global burden of disease with a higher incidence in sub-Saharan Africa. Thus, the aim of this study was to determine the isolation rate of bacterial pathogens from pediatric patients with otitis media. Institutional based cross-sectional study was conducted from January 2013-June 2014 in Addis Ababa among 210 pediatrics patients. Demographic, clinical and associated factors data was obtained in face to face interview with guardians/parents by 5 trained nurse data collectors using structured questionnaire. Middle ear drainage swab was collected following all aseptic procedures and transported to the microbiology laboratory. Culture and Antimicrobial sensitivity test were performed according to the standards. The data quality was assured by questionnaire translation, retranslation and pretesting. Reference strains were used as a positive and negative control for biochemical tests, and culture results were cross checked. Data was checked for completeness, consistency and then entered into Epi Info v3.5.1 and analyzed by SPSS v20. Data interpretation was made using graphs, tables, and result statements. A total of 196 middle ear drainage swab samples were analyzed from pediatric patients and of those 95 (48.5%) samples were positive for pathogenic organisms. The major isolate was S. aureus (15.8%) followed by P. aeruginosa (10.9%), Viridians streptococcus (9.9%), S. pneumoniae (8.9%) and S. pyogenes (7.9%). Upper respiratory tract infection history and living in the rural area have shown significant association with the isolation of pathogenic organism, ( p-value = 0.035) and ( p-value = 0.003) respectively. Most of the isolates show a high level of resistance to

  18. Antimicrobial Peptides for Therapeutic Applications: A Review

    Directory of Open Access Journals (Sweden)

    Tsogbadrakh Mishig-Ochir

    2012-10-01

    Full Text Available Antimicrobial peptides (AMPs have been considered as potential therapeutic sources of future antibiotics because of their broad-spectrum activities and different mechanisms of action compared to conventional antibiotics. Although AMPs possess considerable benefits as new generation antibiotics, their clinical and commercial development still have some limitations, such as potential toxicity, susceptibility to proteases, and high cost of peptide production. In order to overcome those obstacles, extensive efforts have been carried out. For instance, unusual amino acids or peptido-mimetics are introduced to avoid the proteolytic degradation and the design of short peptides retaining antimicrobial activities is proposed as a solution for the cost issue. In this review, we focus on small peptides, especially those with less than twelve amino acids, and provide an overview of the relationships between their three-dimensional structures and antimicrobial activities. The efforts to develop highly active AMPs with shorter sequences are also described.

  19. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Skip to common links HHS U.S. Department of Health and Human Services U.S. Food and Drug Administration A to Z Index Follow FDA En Español Search FDA Submit search ... & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet ...

  20. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Skip to common links HHS U.S. Department of Health and Human Services U.S. Food and Drug Administration ... Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet ...

  1. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... menu Skip to common links HHS U.S. Department of Health and Human Services U.S. Food and Drug Administration ... Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More ...

  2. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... More in Antimicrobial Resistance National Antimicrobial Resistance Monitoring System About NARMS 2015 NARMS Integrated Report Data Meetings ... Deutsch | 日本語 | فارسی | English FDA Accessibility Careers FDA Basics FOIA No FEAR ...

  3. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... Pin it Email Print The Food and Drug Administration's (FDA's) Center for Veterinary Medicine (CVM) produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will result in ...

  4. Synthetic mimics of antimicrobial peptides.

    Science.gov (United States)

    Som, Abhigyan; Vemparala, Satyavani; Ivanov, Ivaylo; Tew, Gregory N

    2008-01-01

    Infectious diseases and antibiotic resistance are now considered the most imperative global healthcare problem. In the search for new treatments, host defense, or antimicrobial, peptides have attracted considerable attention due to their various unique properties; however, attempts to develop in vivo therapies have been severely limited. Efforts to develop synthetic mimics of antimicrobial peptides (SMAMPs) have increased significantly in the last decade, and this review will focus primarily on the structural evolution of SMAMPs and their membrane activity. This review will attempt to make a bridge between the design of SMAMPs and the fundamentals of SMAMP-membrane interactions. In discussions regarding the membrane interaction of SMAMPs, close attention will be paid to the lipid composition of the bilayer. Despite many years of study, the exact conformational aspects responsible for the high selectivity of these AMPs and SMAMPs toward bacterial cells over mammalian cells are still not fully understood. The ability to design SMAMPs that are potently antimicrobial, yet nontoxic to mammalian cells has been demonstrated with a variety of molecular scaffolds. Initial animal studies show very good tissue distribution along with more than a 4-log reduction in bacterial counts. The results on SMAMPs are not only extremely promising for novel antibiotics, but also provide an optimistic picture for the greater challenge of general proteomimetics.

  5. Evaluation of antimicrobial properties of cork.

    Science.gov (United States)

    Gonçalves, Filipa; Correia, Patrícia; Silva, Susana P; Almeida-Aguiar, Cristina

    2016-02-01

    Cork presents a range of diverse and versatile properties making this material suitable for several and extremely diverse industrial applications. Despite the wide uses of cork, its antimicrobial properties and potential applications have deserved little attention from industry and the scientific community. Thus, the main purpose of this work was the evaluation of the antibacterial properties of cork, by comparison with commercially available antimicrobial materials (Ethylene-Vinyl Acetate copolymer and a currently used antimicrobial commercial additive (ACA)), following the previous development and optimization of a method for such antimicrobial assay. The AATCC 100-2004 standard method, a quantitative procedure developed for the assessment of antimicrobial properties in textile materials, was used as reference and optimized to assess cork antibacterial activity. Cork displayed high antibacterial activity against Staphylococcus aureus, with a bacterial reduction of almost 100% (96.93%) after 90 minutes of incubation, similar to the one obtained with ACA. A more reduced but time-constant antibacterial action was observed against Escherichia coli (36% reduction of the initial number of bacterial colonies). To complement this study, antibacterial activity was further evaluated for a water extract of cork and an MIC of 6 mg mL(-1) was obtained against the reference strain S. aureus. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Comparison of implementation of selected TMI action plan requirements on operating plants designed by Babcock and Wilcox

    International Nuclear Information System (INIS)

    Thoma, J.O.

    1984-05-01

    This report provides the results of a study conducted by the US Nuclear Regulatory Commission staff to compare the degree to which eight Babcock and Wilcox (B and W) designed licensed nuclear power plants have complied with the requirements in NUREG-0737, Clarification of TMI Action Plan Requirements. The eight licensed operating plants examined are as follows: Arkansas Nuclear One Unit 1 (ANO-1), Crystal River Unit 3, Davis Besse, Oconee Units 1, 2, and 3, Rancho Seco, and Three Mile Island Unit 1 (TMI-1). The purpose of this audit was to establish the progress of the TMI-1 licensee, General Public Utilities (GPU) Nuclear Corporation, in completing the long-term requirements in NUREG-0737 relative to the other B and W licensees examined

  7. Monitoring of antimicrobial resistance among food animals: Principles and limitations

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller

    2004-01-01

    Large amounts of antimicrobial agents are in the production of food animals used for therapy and prophylactics of bacterial infections and in feed to promote growth. The use of antimicrobial agents causes problems in the therapy of infections through the selection for resistance among bacteria...... pathogenic for animals or humans. Current knowledge regarding the occurrence of antimicrobial resistance in food animals, the quantitative impact of the use of different antimicrobial agents on selection for resistance and the most appropriate treatment regimes to limit the development of resistance......, there are major differences between programmes designed to detect changes in a national population, individual herds or groups of animals. In addition, programmes have to be designed differently according to whether the aim is to determine changes in resistance for all antimicrobial agents or only...

  8. Bioelectric action potentials of Procambarus acutus acutus (Girrard) in serially diluted solutions of selected C/sub 6/ hydrocarbons in water

    Energy Technology Data Exchange (ETDEWEB)

    Idoniboye-Obu, B.

    1977-09-01

    The principle of recording the complex action potentials from both neurogenic and myogenic sources by remote electrodes in water is explored in a bioassay assessing the external concentrations of selected water-soluble petroleum hydrocarbons. These petroleum hydrocarbons could bring about the ultimate cessation of impulse generation and propagation in short term exposures. Long before the harsh threshold of the ''death response'' itself is reached, a progressive diminution or irregularity of the biopotentials can indicate proximity to the ''point of no return''. This is particularly so in the locomotor system, which begins to function less and less effectively in decapod Crustacea, commonly known as very active animals. It is suggested that lethal thresholds of water pollution can be established in a systematic manner using selected test organisms, especially those of commercial importance, by such electrophysiological methods.

  9. Insights on antimicrobial resistance, biofilms and the use of phytochemicals as new antimicrobial agents.

    Science.gov (United States)

    Borges, Anabela; Saavedra, Maria J; Simões, Manuel

    2015-01-01

    Antimicrobial resistance is one of the most serious public health problems. This is of particular concern when bacteria become resistant to various antimicrobial agents simultaneously and when they form biofilms. Consequently, therapeutic options for the treatment of infections have become limited, leading frequently to recurrent infections, treatment failure and increase of morbidity and mortality. Both, persistence and spread of antibiotic resistance, in combination with decreased effectiveness and increased toxicity of current antibiotics have emphasized the urgent need to search alternative sources of antimicrobial substances. Plants are recognized as a source of unexplored chemical structures with high therapeutic potential, including antimicrobial activity against clinically important microorganisms. Additionally, phytochemicals (plant secondary metabolites) present several advantages over synthetic molecules, including green status and different mechanisms of action from antibiotics which could help to overcome the resistance problem. In this study, an overview of the main classes of phytochemicals with antimicrobial properties and their mode of action is presented. A revision about the application of phytochemicals for biofilm prevention and control is also done. Moreover, the use of phytochemicals as scaffolds of new functional molecules to expand the antibiotics pipeline is reviewed.

  10. Insight into the mechanism of action and selectivity of caspase-3 reversible inhibitors through in silico studies

    Science.gov (United States)

    Minini, Lucía; Ferraro, Florencia; Cancela, Saira; Merlino, Alicia

    2017-11-01

    Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder worldwide for which there is currently no cure. Recently, caspase-3 has been proposed as a potential therapeutic target for treating AD. Since this enzyme is overexpressed in brains from AD patients its selective modulation by non-covalent inhibitors becomes an interesting strategy in the search of potential drugs against this neuropathology. With this in mind, we have combined molecular docking, molecular dynamics simulations and QM calculations of unliganded caspase-3 and caspase-7 and in complex with a series of known inhibitors of caspase-3 described in the literature in order to assess the structural features responsible for good inhibitory activity and selectivity against this potential target. This work has allowed us to identify hotspots for drug binding as well as the importance of shape and charge distribution for interacting into the substrate binding cleft or into the dimer interface in each enzyme. Our results showed that most selective compounds against caspsase-3 bind into the substrate binding cleft acting as competitive inhibitors whereas in caspase-7 they bind close to an allosteric site at the dimer interface but since they are weakly bound their presence would not be affecting enzyme dynamics or function. In addition, for both enzymes we have found evidence indicating that differences in shape and accessibility exist between the substrate binding site of each monomer which could be modulating the binding affinity of non-covalent molecules.

  11. STUDY OF THE ANTIMICROBIAL PROPERTIES OF CERTAIN SAPROPHYTIC OBLIGATE MARINE FUNGI

    Directory of Open Access Journals (Sweden)

    Kalyuzhnaya O.S.

    2015-05-01

    of E. coli and S. aureus in control and after their cocultivation with fungi Halosphaeriopsis mediosetigera and Nia vibrissa on yeast broth at (37 ± 1 ° C showed that the number of test cells after culturing strains with selected species of marine fungi significantly lower than in control: when cultured with Halosphaeriopsis mediosetigera cell number of E. coli decreased by almost 100 times, and cells of S. aureus - 1000, when cultured with Nia vibrissa number of cells test strains decreased 100 times. These results prove the presence of antimicrobial properties for these species, with observed the same trend as the study of antimicrobial properties of agar diffusion method - both types of fungi inhibit gram-positive and gram-negative bacteria. Conclusions. The study of the antimicrobial properties of some species of saprophytic obligate marine fungi, which are the inhabitants of the north-western Black Sea region: Arenariomyces trifurcata, Ceriosporopsis halima, Corollospora maritima, Halosphaeriopsis mediosetigera, Nia vibrissa, was carried out. It was established that their culture supernatant have antimicrobial activity against gram-positive bacteria, and the last two species - against gram-negative bacteria, such action was not observed against C. albicans. Thus, the selected objects of study are potential producers of antimicrobial substances; it leads to the prospect of further work in this area. Keywords: saprophytic obligate marine fungi, antimicrobial properties

  12. Antimicrobial stewardship initiatives throughout Europe: proven value for money

    Directory of Open Access Journals (Sweden)

    Edwin J.M. Oberjé

    2017-03-01

    Full Text Available Antimicrobial stewardship is recognized as a key component to stop the current European spread of antimicrobial resistance. It has also become evident that antimicrobial resistance is a problem that cannot be tackled by single institutions or physicians. Prevention of antimicrobial resistance needs rigorous actions at ward level, institution level, national level and at supra-national levels. Countries can learn from each other and possibly transplant best practices across borders to prevent antimicrobial resistance. The aim of this study is to highlight some of the success stories of proven cost-effective interventions, and to describe the actions that have been taken, the outcomes that have been found, and the difficulties that have been met. In some cases we came across substantial scope for real-life cost savings. Although the best approach to effectively hinder the spread of antimicrobial resistance remains unclear and may vary significantly among settings, several EU-wide examples demonstrate that cost-effective antimicrobial stewardship is possible. Such examples can encourage others to implement (the most cost-effective elements in their system.

  13. The antimicrobial activity of the Cnicus benedictus L. extracts

    Directory of Open Access Journals (Sweden)

    Annamaria PALLAG

    2009-05-01

    Full Text Available Our goal was to test the antimicrobial effect of the aqueous solutions obtained from the soft extract of Cnicus benedictus L. (Asteraceae family flowers. The test was performed on Mueller - Hinton and blood-agar culture medium, on 8 standardized bacterial strains and microbiological strains obtained from infected secretions, using the diffusimetric method.The antimicrobial action of the plant extracts was confirmed by all bacterial tested strains, which presented inhibition zones, of approximately same values, at solutions with different concentrations. The values we obtained reveal significant differences of the intensity of the antimicrobial activity of the mature and immature flowers extract.

  14. Synergistic action of octopamine receptor agonists on the activity of selected novel insecticides for control of dengue vector Aedes aegypti (Diptera: Culicidae) mosquito.

    Science.gov (United States)

    Ahmed, Mohamed Ahmed Ibrahim; Vogel, Christoph Franz Adam

    2015-05-01

    Studying insecticide resistance in mosquitoes has attracted the attention of many scientists to elucidate the pathways of resistance development and to design novel strategies in order to prevent or minimize the spread and evolution of resistance. Here, we tested the synergistic action of piperonyl butoxide (PBO) and two octopamine receptor (OR) agonists, amitraz (AMZ) and chlordimeform (CDM) on selected novel insecticides to increase their lethal action on the fourth instar larvae of Aedes aegypti L. However, chlorfenapyr was the most toxic insecticide (LC50 = 193, 102, and 48 ng/ml, after 24, 48, and 72 h exposure, respectively) tested. Further, PBO synergized all insecticides and the most toxic combinatorial insecticide was nitenpyram even after 48 and 72 h exposure. In addition, OR agonists significantly synergized most of the selected insecticides especially after 48 and 72 h exposure. The results imply that the synergistic effects of amitraz are a promising approach in increasing the potency of certain insecticides in controlling the dengue vector Ae. aegypti mosquito. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Antimicrobial Resistance in the Food Chain: A Review

    Science.gov (United States)

    Verraes, Claire; Van Boxstael, Sigrid; Van Meervenne, Eva; Van Coillie, Els; Butaye, Patrick; Catry, Boudewijn; de Schaetzen, Marie-Athénaïs; Van Huffel, Xavier; Imberechts, Hein; Dierick, Katelijne; Daube, George; Saegerman, Claude; De Block, Jan; Dewulf, Jeroen; Herman, Lieve

    2013-01-01

    Antimicrobial resistant zoonotic pathogens present on food constitute a direct risk to public health. Antimicrobial resistance genes in commensal or pathogenic strains form an indirect risk to public health, as they increase the gene pool from which pathogenic bacteria can pick up resistance traits. Food can be contaminated with antimicrobial resistant bacteria and/or antimicrobial resistance genes in several ways. A first way is the presence of antibiotic resistant bacteria on food selected by the use of antibiotics during agricultural production. A second route is the possible presence of resistance genes in bacteria that are intentionally added during the processing of food (starter cultures, probiotics, bioconserving microorganisms and bacteriophages). A last way is through cross-contamination with antimicrobial resistant bacteria during food processing. Raw food products can be consumed without having undergone prior processing or preservation and therefore hold a substantial risk for transfer of antimicrobial resistance to humans, as the eventually present resistant bacteria are not killed. As a consequence, transfer of antimicrobial resistance genes between bacteria after ingestion by humans may occur. Under minimal processing or preservation treatment conditions, sublethally damaged or stressed cells can be maintained in the food, inducing antimicrobial resistance build-up and enhancing the risk of resistance transfer. Food processes that kill bacteria in food products, decrease the risk of transmission of antimicrobial resistance. PMID:23812024

  16. Antimicrobial Stewardship in Daily Practice: Managing an Important Resource

    Directory of Open Access Journals (Sweden)

    Nicole Le Saux

    2014-01-01

    Full Text Available Antimicrobial stewardship is a recent concept that embodies the practical, judicious use of antimicrobials to decrease adverse outcomes from antimicrobials while optimizing the treatment of bacterial infections to reduce the emergence of resistant pathogens. The objectives of the present statement are to illustrate the principles of antimicrobial stewardship and to offer practical examples of how to make antimicrobial stewardship part of everyday hospital and outpatient practice. Vital components of antimicrobial stewardship include appropriate testing to diagnose whether infections are viral or bacterial, and using clinical follow-up rather than antibiotics in cases in which the child is not very ill and uncertainty exists. Other specific, important actions include questioning whether positive urine cultures are contaminated when there is no evidence of pyuria or inflammatory changes, and obtaining a chest radiograph to support a diagnosis of bacterial pneumonia. Optimizing the choice and dosage of antimicrobials also reduces the probability of clinical failures and subsequent courses of antimicrobials. A list of common clinical scenarios to promote stewardship is included.

  17. Antimicrobial Peptides in Reptiles

    Science.gov (United States)

    van Hoek, Monique L.

    2014-01-01

    Reptiles are among the oldest known amniotes and are highly diverse in their morphology and ecological niches. These animals have an evolutionarily ancient innate-immune system that is of great interest to scientists trying to identify new and useful antimicrobial peptides. Significant work in the last decade in the fields of biochemistry, proteomics and genomics has begun to reveal the complexity of reptilian antimicrobial peptides. Here, the current knowledge about antimicrobial peptides in reptiles is reviewed, with specific examples in each of the four orders: Testudines (turtles and tortosises), Sphenodontia (tuataras), Squamata (snakes and lizards), and Crocodilia (crocodilans). Examples are presented of the major classes of antimicrobial peptides expressed by reptiles including defensins, cathelicidins, liver-expressed peptides (hepcidin and LEAP-2), lysozyme, crotamine, and others. Some of these peptides have been identified and tested for their antibacterial or antiviral activity; others are only predicted as possible genes from genomic sequencing. Bioinformatic analysis of the reptile genomes is presented, revealing many predicted candidate antimicrobial peptides genes across this diverse class. The study of how these ancient creatures use antimicrobial peptides within their innate immune systems may reveal new understandings of our mammalian innate immune system and may also provide new and powerful antimicrobial peptides as scaffolds for potential therapeutic development. PMID:24918867

  18. Effect of selective blockade of oxygen consumption, glucose transport, and Ca2+ influx on thyroxine action in human mononuclear cells

    DEFF Research Database (Denmark)

    Kvetny, J; Matzen, L E

    1990-01-01

    The effect of selective blockade of cellular glucose transporters, Ca2+ influx, and mitochondrial oxygen consumption on thyroxine (T4)-stimulated oxygen consumption and glucose uptake was examined in human mononuclear blood cells. Blockade of glucose transporters by cytochalasin B (1 x 10(-5) mol....../L) and of Ca2+ influx by alprenolol (1 x 10(-5) mol/L) and verapamil (4 x 10(-4) mol/L) inhibited T4-activated glucose uptaken and reduced T4-stimulated oxygen consumption by 20%. Uncoupling of mitochondrial oxygen consumption by azide (1 x 10(-3) mol/L) inhibited T4-stimulated oxygen consumption, but had...... no effect on glucose uptake. We conclude that T4-stimulated glucose uptake in human mononuclear blood cells is dependent on intact glucose transporters and Ca2+ influx, but not on mitochondrial oxygen consumption. However, oxygen consumption is, in part, dependent on intact glucose uptake....

  19. Diversity in the glucose transporter-4 gene (SLC2A4 in humans reflects the action of natural selection along the old-world primates evolution.

    Directory of Open Access Journals (Sweden)

    Eduardo Tarazona-Santos

    Full Text Available BACKGROUND: Glucose is an important source of energy for living organisms. In vertebrates it is ingested with the diet and transported into the cells by conserved mechanisms and molecules, such as the trans-membrane Glucose Transporters (GLUTs. Members of this family have tissue specific expression, biochemical properties and physiologic functions that together regulate glucose levels and distribution. GLUT4 -coded by SLC2A4 (17p13 is an insulin-sensitive transporter with a critical role in glucose homeostasis and diabetes pathogenesis, preferentially expressed in the adipose tissue, heart muscle and skeletal muscle. We tested the hypothesis that natural selection acted on SLC2A4. METHODOLOGY/PRINCIPAL FINDINGS: We re-sequenced SLC2A4 and genotyped 104 SNPs along a approximately 1 Mb region flanking this gene in 102 ethnically diverse individuals. Across the studied populations (African, European, Asian and Latin-American, all the eight common SNPs are concentrated in the N-terminal region upstream of exon 7 ( approximately 3700 bp, while the C-terminal region downstream of intron 6 ( approximately 2600 bp harbors only 6 singletons, a pattern that is not compatible with neutrality for this part of the gene. Tests of neutrality based on comparative genomics suggest that: (1 episodes of natural selection (likely a selective sweep predating the coalescent of human lineages, within the last 25 million years, account for the observed reduced diversity downstream of intron 6 and, (2 the target of natural selection may not be in the SLC2A4 coding sequence. CONCLUSIONS: We propose that the contrast in the pattern of genetic variation between the N-terminal and C-terminal regions are signatures of the action of natural selection and thus follow-up studies should investigate the functional importance of different regions of the SLC2A4 gene.

  20. Action of selective serotonin reuptake inhibitor on aggressive behavior in adult rat submitted to the neonatal malnutrition

    Directory of Open Access Journals (Sweden)

    Medeiros Jairza Maria Barreto

    2001-01-01

    Full Text Available The effect of the malnutrition during suckling on the aggressiveness was investigated in adult rats treated or not with citalopram, a selective serotonin reuptake inhibitor (SSRI. The animals were divided into two groups according to the diet used: nourished group-- the rats received the control diet with 23% protein during the life; and malnourished group-- the rats had its mothers submitted to diet with 7.8% protein during suckling. At 120 days of age, each group was sub-divided according to the treatment: acute -- consisting a single i.p. injection of saline solution or 20-mg/Kg citalopram; chronic -- consisting the single injections (1 per day during 14 days of saline or 20 mg/Kg citalopram. The acute or chronic treatment with SSRI reduces aggressive response in nourished rats, but not in malnourished ones. Thus, the malnutrition during the critical period of brain development seems to induce durable alterations in the function of the serotoninergic neurotransmission

  1. Antimicrobial (Drug) Resistance Prevention

    Science.gov (United States)

    ... June 6, 2018 HIV Vaccine Elicits Antibodies in Animals that Neutralize Dozens of HIV Strains , June 4, 2018 ... Antimicrobial (Drug) Resistance > Understanding share with facebook share with twitter share ...

  2. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... bacteria. Over time, the use of antimicrobial drugs will result in the development of resistant strains of ... and other key audiences. We hope this animation will make the concept more understandable to non-scientists ...

  3. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... it More sharing options Linkedin Pin it Email Print The Food and Drug Administration's (FDA's) Center for ... issue of antimicrobial resistance is that the subject material appears abstract and is complex. This video was ...

  4. Animation of Antimicrobial Resistance

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    Full Text Available ... produced material may be copied, reproduced, and distributed as long as FDA's Center for Veterinary Medicine is cited as the corporate author. Animation Animation of Antimicrobial Resistance ( ...

  5. What are Antimicrobial Pesticides?

    Science.gov (United States)

    Antimicrobial pesticides are substances or mixtures of substances used to destroy or suppress the growth of harmful microorganisms such as bacteria, viruses, or fungi on inanimate objects and surfaces.

  6. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... complex. This video was designed to make the concept of antimicrobial resistance more real and understandable to ... audiences. We hope this animation will make the concept more understandable to non-scientists by showing how ...

  7. Animation of Antimicrobial Resistance

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    Full Text Available ... NARMS 2015 NARMS Integrated Report Data Meetings and Publications Resources Judicious Use of Antimicrobials Page Last Updated: ... Emergency Preparedness International Programs News & Events Training & Continuing Education Inspections & Compliance Federal, State & Local Officials Consumers Health ...

  8. Animation of Antimicrobial Resistance

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    Full Text Available ... One of the major obstacles to understanding the issue of antimicrobial resistance is that the subject material ... Website Policies U.S. Food and Drug Administration 10903 New Hampshire Avenue Silver Spring, MD 20993 1-888- ...

  9. Animation of Antimicrobial Resistance

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    Full Text Available ... use of antimicrobial drugs will result in the development of resistant strains of bacteria, complicating clinician's efforts ... Inspections & Compliance Federal, State & Local Officials Consumers Health Professionals Science & Research Industry Scroll back to top Popular ...

  10. Antinociceptive action of DBO 17 and DBO 11 in mice: two 3,8 diazabicyclo (3.2.1.) octane derivates with selective mu opioid receptor affinity.

    Science.gov (United States)

    Fadda, P; Barlocco, D; Tronci, S; Cignarella, G; Fratta, W

    1997-11-01

    Two 3,8 diazabicyclo (3.2.1.) octane derivates, namely DBO 17 and DBO 11, were studied for the opioid-like activity. In the rat brain membrane preparation binding studies, DBO 17 and DBO 11 showed a high affinity and selectivity for the mu opioid receptor (Ki's: 5.1 and 25 nM, respectively). DBO 17 and DBO 11 inhibited the nociceptive response in the hot-plate test of mice with ED50 values of 0.16 mg/kg and 0.44 mg/kg, respectively. The antinociceptive action of both DBO 17 and DBO 11 was blocked by naloxone. Tolerance to the antinociceptive action of DBO 17 and DBO 11 was present after 13 and 7 days of repeated treatment, respectively. Both DBO 17 and DBO 11 were ineffective in morphine-tolerant mice and vice versa. Chronic treatments (three times daily for seven consecutive days) of DBO 17 and DBO 11 induced a naloxone-precipitated withdrawal syndrome in DBO 17 treated mice similar to that in morphine treated mice, whereas in DBO 11 treated mice abstinence signs were virtually absent. These results indicate an interesting pharmacological profile that suggests these compounds as possible new candidates for the clinical treatment of pain.

  11. Social Complexity and Nesting Habits Are Factors in the Evolution of Antimicrobial Defences in Wasps

    OpenAIRE

    Hoggard, Stephen J.; Wilson, Peter D.; Beattie, Andrew J.; Stow, Adam J.

    2011-01-01

    Microbial diseases are important selective agents in social insects and one major defense mechanism is the secretion of cuticular antimicrobial compounds. We hypothesized that given differences in group size, social complexity, and nest type the secretions of these antimicrobials will be under different selective pressures. To test this we extracted secretions from nine wasp species of varying social complexity and nesting habits and assayed their antimicrobial compounds against cultures of S...

  12. Impact of formulary restriction with prior authorization by an antimicrobial stewardship program.

    Science.gov (United States)

    Reed, Erica E; Stevenson, Kurt B; West, Jessica E; Bauer, Karri A; Goff, Debra A

    2013-02-15

    In an era of increasing antimicrobial resistance and few antimicrobials in the developmental pipeline, many institutions have developed antimicrobial stewardship programs (ASPs) to help implement evidence-based (EB) strategies for ensuring appropriate utilization of these agents. EB strategies for accomplishing this include formulary restriction with prior authorization. Potential limitations to this particular strategy include delays in therapy, prescriber pushback, and unintended increases in use of un-restricted antimicrobials; however, our ASP found that implementing prior authorization for select antimicrobials along with making a significant effort to educate clinicians on criteria for use ensured more appropriate prescribing of these agents, hopefully helping to preserve their utility for years to come.

  13. Associations of antimicrobial use with antimicrobial resistance in Campylobacter coli from grow-finish pigs in Japan.

    Science.gov (United States)

    Ozawa, M; Makita, K; Tamura, Y; Asai, T

    2012-10-01

    To determine associations between antimicrobial use and antimicrobial resistance in Campylobacter coli, 155 isolates were obtained from the feces of apparently healthy grow-finish pigs in Japan. In addition, data on the use of antibiotics collected through the national antimicrobial resistance monitoring system in Japan were used for the analysis. Logistic regression was used to identify risk factors to antimicrobial resistance in C. coli in pigs for the following antimicrobials: ampicillin, dihydrostreptomycin, erythromycin, oxytetracycline, chloramphenicol, and enrofloxacin. The data suggested the involvement of several different mechanisms of resistance selection. The statistical relationships were suggestive of co-selection; use of macrolides was associated with enrofloxacin resistance (OR=2.94; CI(95%): 0.997, 8.68) and use of tetracyclines was associated with chloramphenicol resistance (OR=2.37; CI(95%): 1.08, 5.19). The statistical relationships were suggestive of cross-resistance: use of macrolides was associated with erythromycin resistance (OR=9.36; CI(95%): 2.96, 29.62) and the use of phenicols was associated with chloramphenicol resistance (OR=11.83; CI(95%): 1.41, 99.44). These data showed that the use of antimicrobials in pigs selects for resistance in C. coli within and between classes of antimicrobials. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Antimicrobial blue light: a drug-free approach for inactivating pathogenic microbes

    Science.gov (United States)

    Wang, Ying; Dai, Tianhong

    2018-02-01

    Due to the growing global threat of antibiotic resistance, there is a critical need for the development of alternative therapeutics for infectious diseases. Antimicrobial blue light (aBL), as an innovative non-antibiotic approach, has attracted increasing attention. This paper discussed the basic concepts of aBL and recent findings in the studies of aBL. It is commonly hypothesized that the antimicrobial property of aBL is attributed to the presence of endogenous photosensitizing chromophores in microbial cells, which produce cytotoxic reactive oxygen species upon light irradiation. A wide range of important microbes are found to be susceptible to aBL inactivation. Studies have also shown there exist therapeutic windows where microbes are selectively inactivated by aBL while host cells are preserved. The combination of aBL with some other agents result in synergistically improved antimicrobial efficacy. Future efforts should be exerted on the standardization of study design for evaluating aBL efficacy, further elucidation of the mechanism of action, optimization of the technical parameters, and translation of this technique to clinic.

  15. Antimicrobial mechanism of flavonoids against Escherichia coli ATCC 25922 by model membrane study

    International Nuclear Information System (INIS)

    He, Mengying; Wu, Ting; Pan, Siyi; Xu, Xiaoyun

    2014-01-01

    Antimicrobial mechanism of four flavonoids (kaempferol, hesperitin, (+)-catechin hydrate, biochanin A) against Escherichia coli ATCC 25922 was investigated through cell membranes and a liposome model. The release of bacterial protein and images from transmission electron microscopy demonstrated damage to the E. coli ATCC 25922 membrane. A liposome model with dipalmitoylphosphatidylethanolamine (DPPE) (0.6 molar ratio) and dipalmitoylphosphatidylglycerol (DPPG) (0.4 molar ratio), representative of the phospholipid membrane of E. coli ATCC 25922, was used to specify the mode of action of four selected flavonoids through Raman spectroscopy and differential scanning calorimetry. It is suggested that for flavonoids, to be effective antimicrobials, interaction with the polar head-group of the model membrane followed by penetration into the hydrophobic regions must occur. The antimicrobial efficacies of the flavonoids were consistent with liposome interaction activities, kaempferol > hesperitin > (+)-catechin hydrate > biochanin A. This study provides a liposome model capable of mimicking the cell membrane of E. coli ATCC 25922. The findings are important in understanding the antibacterial mechanism on cell membranes.

  16. Antimicrobial mechanism of flavonoids against Escherichia coli ATCC 25922 by model membrane study

    Energy Technology Data Exchange (ETDEWEB)

    He, Mengying; Wu, Ting; Pan, Siyi; Xu, Xiaoyun, E-mail: xiaoyunxu88@gmail.com

    2014-06-01

    Antimicrobial mechanism of four flavonoids (kaempferol, hesperitin, (+)-catechin hydrate, biochanin A) against Escherichia coli ATCC 25922 was investigated through cell membranes and a liposome model. The release of bacterial protein and images from transmission electron microscopy demonstrated damage to the E. coli ATCC 25922 membrane. A liposome model with dipalmitoylphosphatidylethanolamine (DPPE) (0.6 molar ratio) and dipalmitoylphosphatidylglycerol (DPPG) (0.4 molar ratio), representative of the phospholipid membrane of E. coli ATCC 25922, was used to specify the mode of action of four selected flavonoids through Raman spectroscopy and differential scanning calorimetry. It is suggested that for flavonoids, to be effective antimicrobials, interaction with the polar head-group of the model membrane followed by penetration into the hydrophobic regions must occur. The antimicrobial efficacies of the flavonoids were consistent with liposome interaction activities, kaempferol > hesperitin > (+)-catechin hydrate > biochanin A. This study provides a liposome model capable of mimicking the cell membrane of E. coli ATCC 25922. The findings are important in understanding the antibacterial mechanism on cell membranes.

  17. Antimicrobial stewardship in long-term care facilities in Belgium: a questionnaire-based survey of nursing homes to evaluate initiatives and future developments

    Directory of Open Access Journals (Sweden)

    François Kidd

    2016-03-01

    Full Text Available Abstract Background The use of antimicrobials is intense and often inappropriate in long-term care facilities. Antimicrobial resistance has increased in acute and chronic care facilities, including those in Belgium. Evidence is lacking concerning antimicrobial stewardship programmes in chronic care settings. The medical coordinator practicing in Belgian nursing homes is a general practitioner designated to coordinate medical activity. He is likely to be the key position for effective implementation of such programmes. The aim of this study was to evaluate past, present, and future developments of antimicrobial stewardship programmes by surveying medical coordinators working in long-term care facilities in Belgium. Methods We conducted an online questionnaire-based survey of 327 Belgian medical coordinators. The questionnaire was composed of 33 questions divided into four sections: characteristics of the respondents, organisational frameworks for implementation of the antimicrobial stewardship programme, tools to promote appropriate antimicrobial use and priorities of action. Questions were multiple choice, rating scale, or free text. Results A total of 39 medical coordinators (12 % completed the questionnaire. Past or present antimicrobial stewardship initiatives were reported by 23 % of respondents. The possibility of future developments was rated 2.7/5. The proposed key role of medical coordinators was rated <3/5 by 36 % of respondents. General practitioners, nursing staff, and hospital specialists are accepted as important roles. The use of antimicrobial guidelines was reported by only 19 % of respondents. Education was considered the cornerstone for any future developments. Specific diagnostic recommendations were considered useful, but chest x-rays were judged difficult to undertake. The top priority identified was to reduce unnecessary treatment of asymptomatic urinary infections. Conclusions Our study shows that the implementation of

  18. Global Governance Mechanisms to Address Antimicrobial Resistance.

    Science.gov (United States)

    Padiyara, Ponnu; Inoue, Hajime; Sprenger, Marc

    2018-01-01

    Since their discovery, antibiotics, and more broadly, antimicrobials, have been a cornerstone of modern medicine. But the overuse and misuse of these drugs have led to rising rates of antimicrobial resistance, which occurs when bacteria adapt in ways that render antibiotics ineffective. A world without effective antibiotics can have drastic impacts on population health, global development, and the global economy. As a global common good, antibiotic effectiveness is vulnerable to the tragedy of the commons, where a shared limited resource is overused by a community when each individual exploits the finite resource for their own benefit. A borderless threat like antimicrobial resistance requires global governance mechanisms to mitigate its emergence and spread, and it is the responsibility of all countries and relevant multilateral organizations. These mechanisms can be in the form of legally binding global governance mechanisms such as treaties and regulatory standards or nonbinding mechanisms such as political declarations, resolutions, or guidelines. In this article, we argue that while both are effective methods, the strong, swift, and coordinated action needed to address rising rates of antimicrobial resistance will be better served through legally binding governance mechanisms.

  19. Antimicrobial drugs for treating cholera

    Science.gov (United States)

    Leibovici-Weissman, Ya'ara; Neuberger, Ami; Bitterman, Roni; Sinclair, David; Salam, Mohammed Abdus; Paul, Mical

    2014-01-01

    Background Cholera is an acute watery diarrhoea caused by infection with the bacterium Vibrio cholerae, which if severe can cause rapid dehydration and death. Effective management requires early diagnosis and rehydration using oral rehydration salts or intravenous fluids. In this review, we evaluate the additional benefits of treating cholera with antimicrobial drugs. Objectives To quantify the benefit of antimicrobial treatment for patients with cholera, and determine whether there are differences between classes of antimicrobials or dosing schedules. Search methods We searched the Cochrane Infectious Disease Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL); PubMed; EMBASE; African Index Medicus; LILACS; Science Citation Index; metaRegister of Controlled Trials; WHO International Clinical Trials Registry Platform; conference proceedings; and reference lists to March 2014. Selection criteria Randomized and quasi-randomized controlled clinical trials in adults and children with cholera that compared: 1) any antimicrobial treatment with placebo or no treatment; 2) different antimicrobials head-to-head; or 3) different dosing schedules or different durations of treatment with the same antimicrobial. Data collection and analysis Two reviewers independently applied inclusion and exclusion criteria, and extracted data from included trials. Diarrhoea duration and stool volume were defined as primary outcomes. We calculated mean difference (MD) or ratio of means (ROM) for continuous outcomes, with 95% confidence intervals (CI), and pooled data using a random-effects meta-analysis. The quality of evidence was assessed using the GRADE approach. Main results Thirty-nine trials were included in this review with 4623 participants. Antimicrobials versus placebo or no treatment Overall, antimicrobial therapy shortened the mean duration of diarrhoea by about a day and a half compared to placebo or no treatment (MD -36.77 hours, 95% CI -43

  20. Advances in pharmacovigilance initiatives surrounding antimicrobial resistance-Indian perspective.

    Science.gov (United States)

    Bairy, Laxminarayana Kurady; Nayak, Veena; A, Avinash; Kunder, Sushil Kiran

    2016-08-01

    In recent years the development of antimicrobial resistance has been accelerating, the discovery of new antimicrobial agents has slowed substantially in past decades. This review mainly focuses on the problem of antimicrobial resistance(AMR); the various contributor mechanisms, consequences and future of AMR. The review also highlights the irrational use of antimicrobials, improving their usage and problems associated with pharmacovigilance of antimicrobial resistance. Pharmacovigilance in the form of surveillance of antibiotic use is being done in 90% of the countries worldwide through the WHONET program developed by WHO. However, the data comes from a limited area of the globe. Data from every part of the world is required, so that there is geographical representation of every region. A major hurdle in quantifying the extent of antimicrobial resistance is the fact that there are several known microbes, that may turn out to be resistant to one or more of the several known antimicrobial agents. The global action plan initiated by WHO, if implemented successfully will definitely reduce AMR and will help in evaluating treatment interventions.

  1. Freedom in Action

    NARCIS (Netherlands)

    Miltenburg, N. van

    2015-01-01

    Free will is the capacity to select and execute one really possible action alternative. In recent years this simple libertarian picture of our capacity to freely act has drawn much criticism. Many neuroscientists claim that we do not have a capacity to select alternative courses of action since our

  2. Associations of antimicrobial uses with antimicrobial resistance of fecal Escherichia coli from pigs on 47 farrow-to-finish farms in Ontario and British Columbia

    OpenAIRE

    Akwar, Holy T.; Poppe, Cornelis; Wilson, Jeff; Reid-Smith, Richard J.; Dyck, Monica; Waddington, Josh; Shang, Dayue; McEwen, Scott A.

    2008-01-01

    This study assessed the associations between antimicrobial use and other management practices in pigs and antimicrobial resistance in generic Escherichia coli recovered from feces of weaner and finisher pigs on 39 purposefully selected farrow-to-finish farms in Ontario and 8 in British Columbia. Antimicrobials (n = 13), most frequently penicillins and tetracycline, were administered to different age groups of pigs on study farms through various routes of administration. Logistic regression wa...

  3. Ribociclib (LEE011): Mechanism of Action and Clinical Impact of This Selective Cyclin-Dependent Kinase 4/6 Inhibitor in Various Solid Tumors.

    Science.gov (United States)

    Tripathy, Debu; Bardia, Aditya; Sellers, William R

    2017-07-01

    The cyclin D-cyclin-dependent kinase (CDK) 4/6-p16-retinoblastoma (Rb) pathway is commonly disrupted in cancer, leading to abnormal cell proliferation. Therapeutics targeting this pathway have demonstrated antitumor effects in preclinical and clinical studies. Ribociclib is a selective, orally bioavailable inhibitor of CDK4 and CDK6, which received FDA approval in March 2017 and is set to enter the treatment landscape alongside other CDK4/6 inhibitors, including palbociclib and abemaciclib. Here, we describe the mechanism of action of ribociclib and review preclinical and clinical data from phase I, II, and III trials of ribociclib across different tumor types, within the context of other selective CDK4/6 inhibitors. The pharmacokinetics, pharmacodynamics, safety, tolerability, and clinical responses with ribociclib as a single agent or in combination with other therapies are discussed, and an overview of the broad portfolio of ongoing clinical trials with ribociclib across a wide range of indications is presented. On the basis of the available data, ribociclib has a manageable tolerability profile and therapeutic potential for a variety of cancer types. Its high selectivity makes it an important partner drug for other targeted therapies, and it has been shown to enhance the clinical activity of existing anticancer therapies and delay the development of treatment resistance, without markedly increasing toxicity. Ongoing trials of doublet and triplet targeted therapies containing ribociclib seek to identify optimal CDK4/6-based targeted combination regimens for various tumor types and advance the field of precision therapeutics in oncology. Clin Cancer Res; 23(13); 3251-62. ©2017 AACR . ©2017 American Association for Cancer Research.

  4. Antiproliferative and antimicrobial efficacy of the compounds isolated from the roots of Oenothera biennis L.

    Science.gov (United States)

    Singh, Shilpi; Dubey, Vijaya; Singh, Dhananjay Kumar; Fatima, Kaneez; Ahmad, Ateeque; Luqman, Suaib

    2017-09-01

    Oenothera biennis L., commonly known as evening primrose, harbours the flavonoids, steroids, tannins, fatty acids and terpenoids responsible for a diverse range of biological activity, such as antitumour, anti-arthritic and anti-inflammatory effects. In addition to the previous reports from aerial parts of this plant, studies related to antiproliferative or antimicrobial activity from the roots are warranted. To investigate antiproliferative and antimicrobial activity of compounds/mixture (1-8) isolated and characterized from the roots of O. biennis L. A possible mechanism of antiproliferative activity was also studied by targeting ornithine decarboxylase (ODC) and cathepsin D (CATD). Antiproliferative efficacy of the compounds/mixture was examined in selected cancer cell lines along with their probable mechanism of action. The antimicrobial activity was also studied against selected microbes (bacteria and fungi). Antiproliferative potential was evaluated by MTT assay against selected cell lines. The mechanism of action was studied spectrophotometrically by targeting ODC and CATD using both an in-vitro and an in-silico approach. The antimicrobial efficiency was analysed using the disc diffusion and broth dilution methods. Oenotheralanosterol B (3) and the mixture of oenotheralanosterol A and oenotheralanosterol B (4) exhibited antiproliferative activity against breast, hepatic, prostate and leukaemia cancer cell lines as well as in mouse macrophages (IC 50 8.35-49.69 μg/ml). Oenotheralanosterol B (3) and the mixture of oenotheralanosterol A and oenotheralanosterol B (4) displayed a strong molecular interaction with succinate dehydrogenase (binding energy -6.23 and -6.84 kcal/mol and Ki 27.03 and 9.6 μm, respectively). Oenotheralanosterol A (1), oenotheralanosterol B (3) and mixture of oenotheralanosterol A and oenotheralanosterol B (4) potently inhibited the ODC activity with IC 50 ranging from 4.65 ± 0.35 to 19.06 ± 4.16 μg/ml and also showed a

  5. Self-stratifying antimicrobial coatings

    NARCIS (Netherlands)

    Yagci, M.B.

    2012-01-01

    Today, antimicrobial polymers/coatings are widely used in various areas, such as biomedical devices, pharmaceuticals, hospital buildings, textiles, food processing, and contact lenses, where sanitation is needed. Such wide application facilities have made antimicrobial materials very attractive for

  6. Antimicrobial stewardship: Limits for implementation

    NARCIS (Netherlands)

    Sinha, Bhanu

    2014-01-01

    Antibiotic stewardship programme (ASP) is a multifaceted approach to improve patients' clinical outcomes, prevent the emergence of antimicrobial resistance, and reduce hospital costs by prudent and focused antimicrobial use. Development of local treatment guidelines according to local ecology, rapid

  7. General principles of antimicrobial therapy.

    Science.gov (United States)

    Leekha, Surbhi; Terrell, Christine L; Edson, Randall S

    2011-02-01

    Antimicrobial agents are some of the most widely, and often injudiciously, used therapeutic drugs worldwide. Important considerations when prescribing antimicrobial therapy include obtaining an accurate diagnosis of infection; understanding the difference between empiric and definitive therapy; identifying opportunities to switch to narrow-spectrum, cost-effective oral agents for the shortest duration necessary; understanding drug characteristics that are peculiar to antimicrobial agents (such as pharmacodynamics and efficacy at the site of infection); accounting for host characteristics that influence antimicrobial activity; and in turn, recognizing the adverse effects of antimicrobial agents on the host. It is also important to understand the importance of antimicrobial stewardship, to know when to consult infectious disease specialists for guidance, and to be able to identify situations when antimicrobial therapy is not needed. By following these general principles, all practicing physicians should be able to use antimicrobial agents in a responsible manner that benefits both the individual patient and the community.

  8. Structural, physicochemical characterization and antimicrobial ...

    Indian Academy of Sciences (India)

    Structural, physicochemical characterization and antimicrobial activities of a new Tetraaqua ... Antimicrobial activity of 1 was tested. ... was prepared as good quality yellow single crystals .... at 540 nm. Increase of OD was compared to control.

  9. CHEMICAL COMPOSITION, ANTIMICROBIAL AND ANTIOXYDANT ...

    African Journals Online (AJOL)

    VOUNDI

    2016-04-20

    Apr 20, 2016 ... antimicrobial activities of some spices' essential oils on ... antimicrobial effect of their essential oils on some food pathogenic bacteria, namely, Staphylococcus aureus ...... by Origanum compactum essential oil. J. Appl.

  10. Study of antimicrobial property of some hypoglycemic drugs

    Directory of Open Access Journals (Sweden)

    Arun Kumar Dash

    2011-01-01

    Full Text Available In the present work, a comparative antimicrobial study of different hypoglycemic drugs (Metformin, Phenformin, and Rosiglitazone was carried out. The main objective was to ascertain the antimicrobial activity by using "non-antibiotics" as the test substances. The antimicrobial activity was carried out against different bacteria and fungi namely Bacillus liceniformis, Escherichia coli, Proteus vulgaris, Pseudomonas aeruginosa, Shigella flexneri, Bacillus subtilis, Staphylococcus aureus subspp., and Staphylococcus epidermidis by using disc diffusion method and agar dilution method. Ciprofloxacin was taken as the standard antibiotic. The entire procedure was carried out in an aseptic area under the laminar flow by inoculating the bacterial strain to the agar media in which the drug solution was added. Different concentrations (300 and 400 μg/ml of the standard antibiotic and selected drugs were subjected for minimum inhibitory concentration, and zone of inhibition tests and the antimicrobial activity of the selected drugs were determined.

  11. Antimicrobial effectiveness of bioactive packaging materials from edible chitosan and casein polymers: assessment on carrot, cheese, and salami.

    Science.gov (United States)

    Moreira, Maria del Rosario; Pereda, Mariana; Marcovich, Norma E; Roura, Sara I

    2011-01-01

    Antimicrobial packaging is one of the most promising active packaging systems for controlling spoilage and pathogenic microorganisms. In this work, the intrinsic antimicrobial properties of chitosan (CH) were combined with the excellent thermoplastic and film-forming properties of sodium caseinate (SC) to prepare SC/CH film-forming solutions and films. The antimicrobial effectiveness of SC, CH, and SC/CH coatings on the native microfloras of cheese, salami, and carrots was evaluated. In vitro assays through the test tube assay indicated that the most significant antimicrobial effect was achieved by CH and SC/CH solutions on carrot and cheese native microfloras. SC film-forming solutions did not exert antimicrobial activity on any of the native microflora studied. SC, CH, and SC/CH films stored in controlled environments showed that the retention of the antimicrobial action was observed until 5-d storage, at 65% relative humidity in both temperatures (10 °C and 20 °C). In vivo assays were also performed with SC, CH, and SC/CH applied as coatings or wrappers on the 3 food substrates. CH and SC/CH applied at both immersion and wrapper exerted a significant bactericidal action on mesophilic, psychrotrophic, and yeasts and molds counts, showing the 3 microbial populations analyzed a significant reduction (2.0 to 4.5 log CFU/g). An improvement of the bactericidal properties of the CH/SC blend respect to those of the neat CH film is reported. The ionic interaction between both macromolecules enhances its antimicrobial properties. Practical Application: The continuous consumer interest in high quality and food safety, combined with environmental concerns has stimulated the development and study of biodegradable coatings that avoid the use of synthetic materials. Among them, edible coatings, obtained from generally recognized as safe (GRAS) materials, have the potential to reduce weight loss, respiration rate, and improve food appearance and integrity. They can be used in

  12. Antimicrobial and modulation effects of selected Ghanaian ...

    African Journals Online (AJOL)

    The ethanol extracts of the three plants studied here are good modulators as they reduced the MIC of ciprofloxacin and ketoconazole by factors that are comparable to that of reserpine. However the exact compounds and their exact mechanism of modulation require further investigation. Keywords: Anti-infective, modulation, ...

  13. Antimicrobial activities of some selected Nigerian mushrooms ...

    African Journals Online (AJOL)

    ... were either weakly inhibited or not inhibited at all. The minimum inhibitory concentration (MIC) ranged between 1.25 and 9.00mg/ml for bacteria and between 10.50 and 17.50mg/ml for fungi. These results are discussed in relation to therapeutic value of the studied mushrooms. African Journal of Biomedical Research Vol.

  14. Antimicrobial activity of selected corticolous macrolichens | Prashith ...

    African Journals Online (AJOL)

    Science, Technology and Arts Research Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 4, No 3 (2015) >. Log in or Register to get access to full text downloads.

  15. Antimicrobial Peptides (AMPs

    Directory of Open Access Journals (Sweden)

    Mehrzad Sadredinamin

    2016-04-01

    Full Text Available Antimicrobial peptides (AMPs are extensive group of molecules that produced by variety tissues of invertebrate, plants, and animal species which play an important role in their immunity response. AMPs have different classifications such as; biosynthetic machines, biological sources, biological functions, molecular properties, covalent bonding patterns, three dimensional structures, and molecular targets.These molecules have multidimensional properties including antimicrobial activity, antiviral activity, antifungal activity, anti-parasite activity, biofilm control, antitumor activity, mitogens activity and linking innate to adaptive immunity that making them promising agents for therapeutic drugs. In spite of this advantage of AMPs, their clinical developments have some limitation for commercial development. But some of AMPs are under clinical trials for the therapeutic purpose such as diabetic foot ulcers, different bacterial infections and tissue damage. In this review, we emphasized on the source, structure, multidimensional properties, limitation and therapeutic applications of various antimicrobial peptides.

  16. Antimicrobial agents are societal drugs: how should this influence prescribing?

    Science.gov (United States)

    Sarkar, Paul; Gould, Ian M

    2006-01-01

    This paper is concerned with how those who prescribe antimicrobials should consider the wider repercussions of their actions. It is accepted that in an ecological system, pressure will cause evolution; this is also the case with antimicrobials, the result being the development of resistance and the therapeutic failure of drugs. To an extent, this can be ameliorated through advances by the pharmaceutical industry, but that should not stop us from critically appraising our use and modifying our behavior to slow this process down. Up to 50% of prescribing in human medicine and 80% in veterinary medicine and farming has been considered questionable. The Alliance for the Prudent Use of Antimicrobials (APUA) was approached by the WHO to review the situation. Their recommendations include decreasing the prescribing of antibacterials for nonbacterial infections. In the UK, there has been an initiative called "the path of least resistance". This encourages general practitioners to avoid prescribing or reduce the duration of prescriptions for conditions such as upper respiratory tract infections and uncomplicated urinary tract infections; this approach has been successful. Another recommendation is to reduce the prescribing of broad-spectrum antibacterials. In UK hospitals, the problems identified with the inappropriate use of antibacterials are insufficient training in infectious disease, difficulty in selecting empirical antibacterial therapy, poor use of available microbiological information, the fear of litigation and the fact that the majority of antibacterials are prescribed by the least experienced doctors. With close liaison between the laboratories and clinicians, and the development of local protocols, this can be addressed. Another recommendation is to tighten the use of antibacterial prophylaxis and to improve patient compliance. Through a combination of improved education for doctors and patients, and improved communication skills, these problems can be

  17. Screening of antimicrobial potential of in vitro calli and adult leaf ...

    African Journals Online (AJOL)

    pc

    2013-02-27

    Feb 27, 2013 ... varying inhibitory action against the test organisms. ... methods could lead to maintain bioactive potential of plants and to formulate antimicrobial drugs of .... aerogenes (Gram negative bacteria) and a fungus, Candida albicans ...

  18. Antimicrobial Drugs in the Home

    Centers for Disease Control (CDC) Podcasts

    Survey participants in the United Kingdom admitted keeping leftover antimicrobial drugs for future use and taking them without medical advice. Dr. J. Todd Weber, director of CDC's Office of Antimicrobial Resistance, advises against the practice, which can be dangerous and can promote antimicrobial drug resistance.

  19. Global trends in antimicrobial use in food animals

    Science.gov (United States)

    Van Boeckel, Thomas P.; Brower, Charles; Gilbert, Marius; Grenfell, Bryan T.; Levin, Simon A.; Robinson, Timothy P.; Teillant, Aude; Laxminarayan, Ramanan

    2015-01-01

    Demand for animal protein for human consumption is rising globally at an unprecedented rate. Modern animal production practices are associated with regular use of antimicrobials, potentially increasing selection pressure on bacteria to become resistant. Despite the significant potential consequences for antimicrobial resistance, there has been no quantitative measurement of global antimicrobial consumption by livestock. We address this gap by using Bayesian statistical models combining maps of livestock densities, economic projections of demand for meat products, and current estimates of antimicrobial consumption in high-income countries to map antimicrobial use in food animals for 2010 and 2030. We estimate that the global average annual consumption of antimicrobials per kilogram of animal produced was 45 mg⋅kg−1, 148 mg⋅kg−1, and 172 mg⋅kg−1 for cattle, chicken, and pigs, respectively. Starting from this baseline, we estimate that between 2010 and 2030, the global consumption of antimicrobials will increase by 67%, from 63,151 ± 1,560 tons to 105,596 ± 3,605 tons. Up to a third of the increase in consumption in livestock between 2010 and 2030 is imputable to shifting production practices in middle-income countries where extensive farming systems will be replaced by large-scale intensive farming operations that routinely use antimicrobials in subtherapeutic doses. For Brazil, Russia, India, China, and South Africa, the increase in antimicrobial consumption will be 99%, up to seven times the projected population growth in this group of countries. Better understanding of the consequences of the uninhibited growth in veterinary antimicrobial consumption is needed to assess its potential effects on animal and human health. PMID:25792457

  20. Evaluation of antimicrobial and anti-inflammatory activities of seed extracts from six Nigella species.

    Science.gov (United States)

    Landa, Premysl; Marsik, Petr; Havlik, Jaroslav; Kloucek, Pavel; Vanek, Tomas; Kokoska, Ladislav

    2009-04-01

    Seed extracts from six species of the genus Nigella (Family Ranunculaceae)-Nigella arvensis, Nigella damascena, Nigella hispanica, Nigella nigellastrum, Nigella orientalis, and Nigella sativa-obtained by successive extraction with n-hexane, chloroform, and methanol, were tested for their antimicrobial activity against 10 strains of pathogenic bacteria and yeast using the microdilution method as well as for anti-inflammatory properties by in vitro cyclooxygenase (COX)-1 and COX-2 assay. Chemical characterization of active extracts was carried out including free and fixed fatty acid analysis. Comparison of antimicrobial activity showed that N. arvensis chloroform extract was the most potent among all species tested, inhibiting Gram-positive bacterial and yeast strains with minimum inhibitory concentration (MIC) values ranging from 0.25 to 1 mg/mL. With the exception of selective inhibitory action of n-hexane extract of N. orientalis on growth of Bacteroides fragilis (MIC = 0.5 mg/mL), we observed no antimicrobial activity for other Nigella species. Anti-inflammatory screening revealed that N. sativa, N. orientalis, N. hispanica, N. arvensis n-hexane, and N. hispanica chloroform extracts had strong inhibitory activity (more than 80%) on COX-1 and N. orientalis, N. arvensis, and N. hispanica n-hexane extracts were most effective against COX-2, when the concentration of extracts was 100 microg/mL in both COX assays. In conclusion, N. arvensis, N. orientalis, and N. hispanica seeds, for the first time examined for antimicrobial and anti-inflammatory effects, revealed their significant activity in one or both assays.

  1. Reinforcing the membrane-mediated mechanism of action of the anti-tuberculosis candidate drug thioridazine with molecular simulations

    DEFF Research Database (Denmark)

    Kopec, Wojciech; Khandelia, Himanshu

    2014-01-01

    Thioridazine is a well-known dopamine-antagonist drug with a wide range of pharmacological properties ranging from neuroleptic to antimicrobial and even anticancer activity. Thioridazine is a critical component of a promising multi-drug therapy against M. tuberculosis. Amongst the various propose......-membrane interactions, and reinforce the wider, emerging view of action of many small, bioactive compounds....... mechanisms of action, the cell membrane-mediated one is peculiarly tempting due to the distinctive feature of phenothiazine drug family to accumulate in selected body tissues. In this study, we employ long-scale molecular dynamics simulations to investigate the interactions of three different concentrations...

  2. The antimicrobial resistance crisis: causes, consequences, and management.

    Science.gov (United States)

    Michael, Carolyn Anne; Dominey-Howes, Dale; Labbate, Maurizio

    2014-01-01

    The antimicrobial resistance (AMR) crisis is the increasing global incidence of infectious diseases affecting the human population, which are untreatable with any known antimicrobial agent. This crisis will have a devastating cost on human society as both debilitating and lethal diseases increase in frequency and scope. Three major factors determine this crisis: (1) the increasing frequency of AMR phenotypes among microbes is an evolutionary response to the widespread use of antimicrobials; (2) the large and globally connected human population allows pathogens in any environment access to all of humanity; and (3) the extensive and often unnecessary use of antimicrobials by humanity provides the strong selective pressure that is driving the evolutionary response in the microbial world. Of these factors, the size of the human population is least amenable to rapid change. In contrast, the remaining two factors may be affected, so offering a means of managing the crisis: the rate at which AMR, as well as virulence factors evolve in microbial world may be slowed by reducing the applied selective pressure. This may be accomplished by radically reducing the global use of current and prospective antimicrobials. Current management measures to legislate the use of antimicrobials and to educate the healthcare world in the issues, while useful, have not comprehensively addressed the problem of achieving an overall reduction in the human use of antimicrobials. We propose that in addition to current measures and increased research into new antimicrobials and diagnostics, a comprehensive education program will be required to change the public paradigm of antimicrobial usage from that of a first line treatment to that of a last resort when all other therapeutic options have failed.

  3. Th