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Sample records for restrained antimicrobial arylamide

  1. Restraining mechanism

    NASA Technical Reports Server (NTRS)

    Hardy, J. C. (Inventor)

    1970-01-01

    A restraining mechanism restraining a pressurized garment so as to limit its ballooning effect is described. A helically wound spring is bonded at its outer periphery to an elongated flat plate which permits the flat plate to bend in a single direction. The flat plate is attached to an inflatable glove to the palm side for restraining the glove from ballooning when inflated.

  2. Intramolecular hydrogen bonds: ab initio Car Parrinello simulations of arylamide torsions

    NASA Astrophysics Data System (ADS)

    Doerksen, Robert J.; Chen, Bin; Klein, Michael L.

    2003-10-01

    Gas-phase, room temperature Car-Parrinello molecular dynamics simulations using the HCTH density functional are reported for the arylamides acetanilide ( 1) and ortho-methylthioacetanilide ( 2). The simulations show that in 1, rotation around the ring-amide bond is relatively unrestricted. By contrast, in 2 the methylthio side chain encourages the amide to be directed with N-H pointing toward S, not to flip by 360°, and furthermore to remain close to coplanar with the benzene ring. Because of an intramolecular N-H⋯S hydrogen bond, the N-H stretch frequency of 2 is red-shifted by ˜78 cm -1 compared to that of 1.

  3. Inhibition of the Mycobacterium tuberculosis enoyl acyl carrier protein reductase InhA by arylamides

    PubMed Central

    He, Xin; Alian, Akram; Ortiz de Montellano, Paul R.

    2007-01-01

    InhA, the enoyl acyl carrier protein reductase (ENR) from Mycobacterium tuberculosis, is one of the key enzymes involved in the type II fatty acid biosynthesis pathway of M. tuberculosis. We report here the discovery, through high-throughput screening, of a series of arylamides as a novel class of potent InhA inhibitors. These direct InhA inhibitors require no mycobacterial enzymatic activation and thus circumvent the resistance mechanism to antitubercular prodrugs such as INH and ETA that is most commonly observed in drug-resistant clinical isolates. The crystal structure of InhA complexed with one representative inhibitor reveals the binding mode of the inhibitor within the InhA active site. Further optimization through a microtiter synthesis strategy followed by in situ activity screening led to the discovery of a potent InhA inhibitor with in vitro IC50 = 90 nM, representing a 34-fold potency improvement over the lead compound. PMID:17723305

  4. Inhibition of the Mycobacterium tuberculosis enoyl acyl carrier protein reductase InhA by arylamides.

    PubMed

    He, Xin; Alian, Akram; Ortiz de Montellano, Paul R

    2007-11-01

    InhA, the enoyl acyl carrier protein reductase (ENR) from Mycobacterium tuberculosis, is one of the key enzymes involved in the type II fatty acid biosynthesis pathway of M. tuberculosis. We report here the discovery, through high-throughput screening, of a series of arylamides as a novel class of potent InhA inhibitors. These direct InhA inhibitors require no mycobacterial enzymatic activation and thus circumvent the resistance mechanism to antitubercular prodrugs such as INH and ETA that is most commonly observed in drug-resistant clinical isolates. The crystal structure of InhA complexed with one representative inhibitor reveals the binding mode of the inhibitor within the InhA active site. Further optimization through a microtiter synthesis strategy followed by in situ activity screening led to the discovery of a potent InhA inhibitor with in vitro IC(50)=90 nM, representing a 34-fold potency improvement over the lead compound. PMID:17723305

  5. Restraining potentially violent patients.

    PubMed

    Splawn, G

    1991-10-01

    People who are emotionally distraught or mentally ill are rarely predictable. A calm, reassuring, but firm and decisive manner is most effective in dealing with out-of-control patients. Staff members should be careful to never position themselves with a potentially violent or distraught patient between them and the door. A room should be emptied of all extraneous, potentially dangerous objects before restraint of a patient. A clear plan of what is to be done and who is to do what is necessary. All staff members should remove glasses, pens, scissors, and other items that are potential weapons before restraining a patient. A humane attitude when restraining patients is extremely important. Sometimes the attitude of those applying restraints can be more traumatic than the actual application of the restraints. It is important that staff members remember that patients who need restraint are not "bad" people. For whatever reason, they have lost the ability to control themselves. These people do not like being out of control; given a choice, they would choose not to be. The staff attitude during this stressful event, which is becoming all too common in the emergency department, can have a tremendous effect on patients who require this procedure. When a patient is restrained in a competent, humane manner, staff members can pride themselves on their skills in dealing successfully with this emergency, just as they can when dealing with a cardiac arrest. Finally, it has been said that you cannot truly understand what another person is going through until you have had the same experience yourself.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1921070

  6. Motion restraining device

    NASA Technical Reports Server (NTRS)

    Ford, A. G. (Inventor)

    1977-01-01

    A motion-restraining device for dissipating at a controlled rate the force of a moving body is discussed. The device is characterized by a drive shaft adapted to be driven in rotation by a moving body connected to a tape wound about a reel mounted on the drive shaft, and an elongated pitman link having one end pivotally connected to the crankshaft and the opposite end thereof connected with the mass through an energy dissipating linkage. A shuttle is disposed within a slot and guided by rectilinear motion between a pair of spaced impact surfaces. Reaction forces applied at impact of the shuttle with the impact surfaces include oppositely projected force components angularly related to the direction of the applied impact forces.

  7. Antimicrobials

    PubMed Central

    Murphy, Eileen F.; Clarke, Siobhan F.; Marques, Tatiana M.; Hill, Colin; Stanton, Catherine; Ross, R. Paul; O’Doherty, Robert M.; Shanahan, Fergus; Cotter, Paul D.

    2013-01-01

    Obesity is associated with a number of serious health consequences, including type 2 diabetes, cardiovascular disease and a variety of cancers among others and has been repeatedly shown to be associated with a higher risk of mortality. The relatively recent discovery that the composition and metabolic activity of the gut microbiota may affect the risk of developing obesity and related disorders has led to an explosion of interest in this distinct research field. A corollary of these findings would suggest that modulation of gut microbial populations can have beneficial effects with respect to controlling obesity. In this addendum, we summarize our recent data, showing that therapeutic manipulation of the microbiota using different antimicrobial strategies may be a useful approach for the management of obesity and metabolic conditions. In addition, we will explore some of the mechanisms that may contribute to microbiota-induced susceptibility to obesity and metabolic diseases. PMID:23018760

  8. Neuromuscular lesions in restrained rabbits.

    PubMed

    Mendlowski, B

    1975-01-01

    Ten of 16 rabbits restrained 6 h daily for 35 days developed focal to diffuse degeneration of the sciatic nerves. Very small necrotic areas also were found in the skeletal muscles of seven of 16 rabbits, but the muscle lesions did not correlate with the nerve changes. PMID:180647

  9. Design, synthesis, and biological evaluation of new arylamide derivatives possessing sulfonate or sulfamate moieties as steroid sulfatase enzyme inhibitors.

    PubMed

    El-Gamal, Mohammed I; Semreen, Mohammad H; Foster, Paul A; Potter, Barry V L

    2016-06-15

    A series of new arylamide derivatives possessing terminal sulfonate or sulfamate moieties was designed and synthesized. The target compounds were tested for in vitro inhibitory effects against the steroid sulfatase (STS) enzyme in a cell-free assay system. The free sulfamate derivative 1j was the most active. It inhibited the enzymatic activity by 72.0% and 55.7% at 20μM and 10μM, respectively. Compound 1j was further tested for STS inhibition in JEG-3 placental carcinoma cells with high STS enzyme activity. It inhibited 93.9% of the enzyme activity in JEG-3 placental carcinoma cells at 20μM with an efficacy near to that of the well-established drug STX64 as reference. At 10μM, 1j inhibited 86.1% of the STS activity of JEG-3. Its IC50 value against the STS enzyme in JEG-3 cells was 0.421μM. Thus, 1j represents an attractive new non-steroidal lead for further optimization. PMID:27143133

  10. Design, synthesis, broad-spectrum antiproliferative activity, and kinase inhibitory effect of triarylpyrazole derivatives possessing arylamides or arylureas moieties.

    PubMed

    Gamal El-Din, Mahmoud M; El-Gamal, Mohammed I; Abdel-Maksoud, Mohammed S; Yoo, Kyung Ho; Oh, Chang-Hyun

    2016-08-25

    A novel series of 1,3,4-triarylpyrazole derivatives possessing terminal arylamide or arylurea terminal moieties has been designed and synthesized. Their in vitro antiproliferative activities were investigated against a panel of 58 cell lines of nine different cancer types at the NCI, USA. The urea analogues 2b, 2c, and 2f as well as the amide derivatives 3e and 3f exerted the highest mean % inhibition values over the 58 cell line panel at 10 μM, and thus were further tested in 5-dose testing mode to determine their GI50, TGI, and LC50 values. The above mentioned compounds have shown stronger antiproliferative activities in terms of potency and efficacy upon comparing their results with Sorafenib as a reference compound. Among them, compounds 2c and 2f possessing 3,4-dichlorophenylurea terminal moiety showed the highest mean %inhibition value of about 99.85 and 104.15% respectively over the 58-cell line panel at 10 μM concentration. Also compounds 2b, 3e, and 3f exhibited mean % inhibition over 80% at 10 μM concentration. The GI50 value of compound 3e over K-562 cancer cell line was 0.75 μM. Accordingly, compound 2f was screened over seven kinases at a single-dose concentration of 10 μM to profile its kinase inhibitory activity. Interestingly, the compound showed highly inhibitory activities (90.44% and 87.71%) against BRAF (V600E) and RAF1 kinases, respectively. Its IC50 value against BRAF (V600E) was 0.77 μM. Compounds 2b, 2c, 2f, 3e, and 3f exerted high selectivity towards cancer cell lines than L132 normal lung cells. PMID:27155467

  11. Apparatus for restraining and transporting dies

    DOEpatents

    Allison, James W.; LaBarre, Timothy L.

    1994-01-01

    Apparatus for restraining and transporting dies in punch press operations is provided. A floatation platen for supporting a die on the platen's upper surface has a plurality of recessed gas exhaust ports on the platen's lower surface. A source of pressurized gas delivers gas to a platen manifold, for delivery to orifices located in the gas exhaust ports. The flow of gas is controlled by a first valve adjacent the gas source and a second valve adjacent the manifold, with the second valve being used to control the gas flow during movement of the die. In this fashion, a die may be moved on a cushion of air from one workstation to a selected second workstation. A moveable hydraulically operated restraining fixture is also provided, for clamping the die in position during the compacting phase, and for releasing the die after completion of the compacting phase by releasing the hydraulic pressure on the restraining fixture. When pressure in the hydraulic cylinders on the restraining fixture is reversed, the restraining fixture will retract so that there is no contact between the die and the restraining fixture, thereby allowing the die to be removed from a first workstation and moved to a second selected workstation.

  12. RESTRAINING SYSTEM FOR PLETHYSMOGRAPHY IN SMALL ANIMALS

    EPA Science Inventory

    A restraining technique for immobilizing awake guinea pigs and rats during physiological measurements is described. The basic device consists of an adjustable acrylic holder that supports the animal in a standing position while restricting movement of the four legs. The holder al...

  13. Reframing and Restraining Directives in the Treatment of Clinical Depression.

    ERIC Educational Resources Information Center

    Swoboda, Joseph S.; And Others

    1990-01-01

    Tested effects of reframing and restraining directives on depression of high- and low-reactant clients (N=74) classified as moderately to severely depressed. Found reframing more effective than restraining or control, and level of reactance had no effect. Restraining did not differ from control. (Author/NB)

  14. Maternal Influences on Daughters' Restrained Eating Behavior

    PubMed Central

    Francis, Lori A.; Birch, Leann L.

    2008-01-01

    This study examined whether mothers' preoccupation with their own weight and eating was linked to daughters' restrained eating behavior. Participants included 173 non-Hispanic, White mother–daughter dyads, measured longitudinally when daughters were ages 5, 7, 9, and 11. Mothers who were preoccupied with their own weight and eating reported higher levels of restricting daughters' intake and encouraging daughters to lose weight over time. Mothers' encouragement of daughters' weight loss was linked to daughters' restrained eating behavior; this relationship was partially mediated by daughters' perception of maternal pressure to lose weight. These findings suggest that mothers' preoccupation with weight and eating, via attempts to influence daughters' weight and eating, may place daughters at risk for developing problematic eating behaviors. PMID:16287400

  15. Maternal influences on daughters' restrained eating behavior.

    PubMed

    Francis, Lori A; Birch, Leann L

    2005-11-01

    This study examined whether mothers' preoccupation with their own weight and eating was linked to daughters' restrained eating behavior. Participants included 173 non-Hispanic, White mother-daughter dyads, measured longitudinally when daughters were ages 5, 7, 9, and 11. Mothers who were preoccupied with their own weight and eating reported higher levels of restricting daughters' intake and encouraging daughters to lose weight over time. Mothers' encouragement of daughters' weight loss was linked to daughters' restrained eating behavior; this relationship was partially mediated by daughters' perception of maternal pressure to lose weight. These findings suggest that mothers' preoccupation with weight and eating, via attempts to influence daughters' weight and eating, may place daughters at risk for developing problematic eating behaviors. PMID:16287400

  16. Restrained optimization of broken-symmetry determinants

    NASA Astrophysics Data System (ADS)

    Herrmann, Carmen; Podewitz, Maren; Reiher, Markus

    The goal of this work is to provide an overview on how Lagrange multipliers can be used in self-consistent-field algorithms for convergence control. In particular, a restrained optimization scheme is proposed with the purpose to guide any set of initial guess molecular orbitals to those of a Slater determinant which (1) has certain expectation values (i.e., molecular properties) within a predefined range and (2) corresponds to a true (local) energy minimum, if such a minimum exists within the property range chosen. The most important practical application of such an algorithm is the calculation of minimum-energy broken-symmetry determinants, which are often used in Kohn-Sham density functional calculations to model antiferromagnetically coupled states. This is achieved by (a) combining a constrained optimization with a subsequent optimization where the constraints are released, i.e., the Lagrange multipliers are set to zero. Alternatively, (b) a modified scheme may be employed, where the constraints are released as soon as the energy starts to rise in the SCF algorithm. Both alternatives are combined with both intermediate and final automatic control of whether the properties of interest are within the desired range. A parameter study using scheme (a) is carried out for a set of small test systems. Applications to a synthetically available trinuclear copper complex and to Crabtree and Brudvig's water-oxidizing complex demonstrate the value and limitations of restrained optimization.

  17. 49 CFR 1103.22 - Restraining clients from improprieties.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Restraining clients from improprieties. 1103.22... Practitioner's Duties and Responsibilities Toward A Client § 1103.22 Restraining clients from improprieties. A practitioner should see that his clients act with the same restraint that the practitioner himself...

  18. Salt restrains maturation in subsalt plays

    SciTech Connect

    Mello, U.T. ); Anderson, R.N.; Karner, G.D. . Lamont-Doherty Earth Observatory)

    1994-01-31

    The thermal positive anomaly associated with the top of salt diapirs has attracted significant attention in modifying the temperature structure and history of a sedimentary basin. Here the authors explore the role of the negative thermal anomaly beneath salt in modifying the maturation history of the source rocks in subsalt sediments. Organic matter maturation is believed to follow temperature dependent chemical reactions. Therefore, any temperature anomaly associated with salt masses affects the nearby maturation of potential source rocks. The level of maturity of source rocks close to salt diapirs will differ from that predicted based on regional trends. The impact of the thermal anomaly on a given point will depend on the duration and distance of the thermal anomaly to this particular point. Consequently, the maturation history of source rocks in salt basins is closely related to the salt motion history, implying that a transient thermal analysis is necessary to evaluate the sure impact on maturation of the thermal anomalies associated with salt diapirism. The paper describes vitrinite kinetics, salt in evolving basins, correlation of salt and temperature, salt dome heat drains, and restrained maturation.

  19. Role of the Conformational Rigidity in the Design of Biomimetic Antimicrobial Compounds

    SciTech Connect

    Ivankin, Andrey; Livne, Liran; Mor, Amram; Caputo, Gregory A.; DeGrado, William F.; Meron, Mati; Lin, Binhua; Gidalevitz, David

    2011-08-16

    A link between structural flexibility of biomimetic antimicrobials and their ability to penetrate into the hydrophobic core and disrupt the integrity of bacterial lipid model membranes has been established using liquid surface X-ray scattering techniques. Results indicate that the modes of interaction of flexible and conformationally restrained antimicrobials with the bacterial membranes are different.

  20. Evolving efficiency of restraining bends within wet kaolin analog experiments

    NASA Astrophysics Data System (ADS)

    Hatem, Alexandra E.; Cooke, Michele L.; Madden, Elizabeth H.

    2015-03-01

    Restraining bends along strike-slip fault systems evolve by both propagation of new faults and abandonment of fault segments. Scaled analog modeling using wet kaolin allows for qualitative and quantitative observations of this evolution. To explore how bend geometry affects evolution, we model bends with a variety of initial angles, θ, from θ = 0° for a straight fault to θ = 30°. High-angle restraining bends (θ ≥ 20°) overcome initial inefficiencies by abandoning unfavorably oriented restraining segments and propagating multiple new, inwardly dipping, oblique-slip faults that are well oriented to accommodate convergence within the bend. Restraining bends with 0° < θ ≤ 15° maintain activity along the restraining bend segment and grow a single new oblique slip fault on one side of the bend. In all restraining bends, the first new fault propagates at ~5 mm of accumulated convergence. Particle Image Velocimetry analysis provides a complete velocity field throughout the experiments. From these data, we quantify the strike-slip efficiency of the system as the percentage of applied plate-parallel velocity accommodated as slip in the direction of plate motion along faults within the restraining bend. Bends with small θ initially have higher strike-slip efficiency compared to bends with large θ. Although they have different fault geometries, all systems with a 5 cm bend width reach a steady strike-slip efficiency of 80% after 50 mm of applied plate displacement. These experimental restraining bends resemble crustal faults in their asymmetric fault growth, asymmetric topographic gradient, and strike-slip efficiency.

  1. Conformationally restrained aromatic analogues of fosmidomycin and FR900098.

    PubMed

    Kurz, Thomas; Schlüter, Katrin; Pein, Miriam; Behrendt, Christoph; Bergmann, Bärbel; Walter, Rolf D

    2007-07-01

    The synthesis and in-vitro antimalarial activity of conformationally restrained bis(pivaloyloxymethyl) ester analogues of the natural product fosmidomycin is presented. In contrast to alpha-aryl-substituted analogues, conformationally restrained aromatic analogues exhibit only moderate in-vitro antimalarial activity against the chloroquine-sensitive strain 3D7 of Plasmodium falciparum. The most active derivative displays an IC(50) value of 47 microM. PMID:17611943

  2. Antimicrobial Stewardship

    PubMed Central

    Doron, Shira; Davidson, Lisa E.

    2011-01-01

    Antimicrobial resistance is increasing; however, antimicrobial drug development is slowing. Now more than ever before, antimicrobial stewardship is of the utmost importance as a way to optimize the use of antimicrobials to prevent the development of resistance and improve patient outcomes. This review describes the why, what, who, how, when, and where of antimicrobial stewardship. Techniques of stewardship are summarized, and a plan for implementation of a stewardship program is outlined. PMID:22033257

  3. Ironic processes in the eating behaviour of restrained eaters.

    PubMed

    Boon, Brigitte; Stroebe, Wolfgang; Schut, Henk; Ijntema, Richta

    2002-02-01

    Theory. The present study examines the processes underlying the disinhibition of the eating behaviour of restrained eaters following negative emotions. Based on Herman and Polivy's (1984) Boundary Model and Wegner's Ironic Process Theory (1994), the limited capacity hypothesis is formulated, suggesting that overeating in restrained eaters results from cognitive capacity limitations. Predictions were that (1) impairment of cognitive capacity during eating will lead to overeating in restrained but not in unrestrained eaters and that (2) this difference should only emerge with food perceived to be high in calories.METHOD: The hypotheses were tested in an experiment with a 2 (restrained/unrestrained) x 2 (distraction yes/no) x 2 (perceived calories high/low) design, in which subjects consumed ice-cream in a taste test situation. Ice-cream consumption was the dependent variable.RESULTS: A second-order interaction was found: as predicted, in the high calorie condition restrained eaters ate the same amount as unrestrained eaters when not distracted, but considerably more when distracted. There was also an unexpected main effect of distraction, which indicated that restrained as well as unrestrained eaters ate more if distracted than if not distracted.DISCUSSION: The restraintxdistractionxperceived calories interaction can be explained by both the Ironic Process Theory and the Boundary Model; and the limited capacity hypothesis appears to be confirmed. The overall main effect of distraction remains puzzling. Two speculative views for the latter effect are offered. PMID:14596713

  4. Antimicrobial peptides

    PubMed Central

    2014-01-01

    With increasing antibiotics resistance, there is an urgent need for novel infection therapeutics. Since antimicrobial peptides provide opportunities for this, identification and optimization of such peptides have attracted much interest during recent years. Here, a brief overview of antimicrobial peptides is provided, with focus placed on how selected hydrophobic modifications of antimicrobial peptides can be employed to combat also more demanding pathogens, including multi-resistant strains, without conferring unacceptable toxicity. PMID:24758244

  5. Keeping guns out of the hands of abusers: handgun purchases and restraining orders.

    PubMed

    Vittes, Katherine A; Sorenson, Susan B

    2008-05-01

    Persons under certain domestic violence restraining orders are prohibited by federal law from purchasing and possessing a firearm. We used administrative data from California to link 794426 restraining orders with 1388724 handgun purchase applications. We found that restrained persons were not a less law-abiding group in general, but they appeared to be repeatedly or serially abusive to intimate partners, and their handgun purchase rates were highest after their restraining orders expired. PMID:18381985

  6. Are Temporary Restraining Orders More Likely to Be Issued When Applications Mention Firearms?

    ERIC Educational Resources Information Center

    Vittes, Katherine A.; Sorenson, Susan B.

    2006-01-01

    Restraining orders, an important legal intervention for victims of domestic violence, have broad potential for injury prevention. Using data from one of the busiest restraining order clinics in the nation, the authors examined 1,354 applicants' descriptions of abuse. Most (89.2%) applicants were issued a restraining order. A total of 16.0% of…

  7. Ulcers in restrained rats: Study of protective substances

    NASA Technical Reports Server (NTRS)

    Buche, L.; Gallaire, D.

    1980-01-01

    The genesis of ulcers in restrained rats is discussed through an investigation of the relationship between the protective effects of nervous system effectual substances examined vis-a-vis ulcers in restrained rats and their elective or secondary pharmacologic effects. The substances used were capable of either peripheral parasympatholytic, sympatholytic, ganglioplegic, spasmolytic effects or central, hypnotic, tranquilizing, neuroleptic, analgesic effects. The regular and considerable protection observed with parasympatholytics (atropine sulfate, benzylonium bromide, dihexyverine, J.L. 1344) and a ganglioplegic (pentamethonium) is a function of their anticholinergic properties. It is of less importance with dibenamine, a sympatholytic action on the adrenergic receptors. Among the central depressive substances tested (hypnotics, tranquilizers, neuroleptics, analgesic), phenobarbital at a nonhypnotic dose, and dextromoramide at a nonanalgesic dose, show antiulcerous effects, which are found with chlorpromazine only at cataleptogenic doses.

  8. Antimicrobial stewardship

    PubMed Central

    Chung, Gladys W.; Wu, Jia En; Yeo, Chay Leng; Chan, Douglas; Hsu, Li Yang

    2013-01-01

    Antimicrobial stewardship is an emerging field currently defined by a series of strategies and interventions aimed toward improving appropriate prescription of antibiotics in humans in all healthcare settings. The ultimate goal is the preservation of current and future antibiotics against the threat of antimicrobial resistance, although improving patient safety and reducing healthcare costs are important concurrent aims. Prospective audit and feedback interventions are probably the most widely practiced of all antimicrobial stewardship strategies. Although labor-intensive, they are more easily accepted by physicians compared with formulary restriction and preauthorization strategies and have a higher potential for educational opportunities. Objective evaluation of antimicrobial stewardship is critical for determining the success of such programs. Nonetheless, there is controversy over which outcomes to measure and there is a pressing need for novel study designs that can objectively assess antimicrobial stewardship interventions despite the limitations inherent in the structure of most such programs. PMID:23302793

  9. Dieting and restrained eating as prospective predictors of weight gain.

    PubMed

    Lowe, Michael R; Doshi, Sapna D; Katterman, Shawn N; Feig, Emily H

    2013-01-01

    Research in normal weight individuals paradoxically suggests that measures of attempted eating restriction might represent robust predictors of weight gain. This review examined the extent to which measures of dieting (e.g., self-reported weight loss dieting in the past year) and dietary restraint (e.g., the Cognitive Restraint scale from the Three-Factor Eating Questionnaire) have prospectively predicted weight change. We located and reviewed 25 prospective studies containing 40 relevant comparisons. Studies were limited to those in which participants were non-obese (with a mean BMI between 18.5 and 30) and averaged at least 12 years old. Neither measure predicted future weight loss. Fifteen of the 20 comparisons (75%) that examined measures of dieting significantly predicted future weight gain whereas only 1 of 20 (5%) that examined restrained eating measures did so. Two plausible explanations for these findings are that: (1) dieters and restrained eaters do not differ in terms of an underlying proneness toward weight gain, but restrained eating represents a more effective means of preventing it; and (2) normal weight individuals who diet do so because they are resisting a powerful predisposition toward weight gain which dieting ultimately fails to prevent. Recent dieting in non-obese individuals may be a valuable proxy of susceptibility to weight gain. This easily assessed characteristic could identify individuals for whom obesity prevention interventions would be particularly appropriate. PMID:24032024

  10. Antimicrobial Polymer

    DOEpatents

    McDonald, William F.; Wright, Stacy C.; Taylor, Andrew C.

    2004-09-28

    A polymeric composition having antimicrobial properties and a process for rendering the surface of a substrate antimicrobial are disclosed. The polymeric composition comprises a crosslinked chemical combination of (i) a polymer having amino group-containing side chains along a backbone forming the polymer, (ii) an antimicrobial agent selected from metals, metal alloys, metal salts, metal complexes and mixtures thereof, and (iii) a crosslinking agent containing functional groups capable of reacting with the amino groups. In one example embodiment, the polymer is a polyamide formed from a maleic anhydride or maleic acid ester monomer and alkylamines thereby producing a polyamide having amino substituted alkyl chains on one side of the polyamide backbone; the crosslinking agent is a phosphine having the general formula (A).sub.3 P wherein A is hydroxyalkyl; and the metallic antimicrobial agent is selected from chelated silver ions, silver metal, chelated copper ions, copper metal, chelated zinc ions, zinc metal and mixtures thereof.

  11. Antimicrobial Resistance

    MedlinePlus

    ... antibiotic are known as methicillin-resistant S. aureus or MRSA. Antibiotics and other antimicrobial drugs first became widely ... factors for infection are known as community-associated MRSA (CA-MRSA). Recently, several cases overseas and in ...

  12. Geomorpho-tectonic evolution of the Jamaican restraining bend

    NASA Astrophysics Data System (ADS)

    Domínguez-González, Leomaris; Andreani, Louis; Stanek, Klaus P.; Gloaguen, Richard

    2015-01-01

    This work applies recent advances in tectonic geomorphology in order to understand the geomorphic evolution of the Jamaican restraining bend located along the Caribbean-Gonâve-North American plate boundary. We propose a classification of landscapes according to their erosional stages. The approach is mainly based on the combination of two DEM-based geomorphic indices: the hypsometric integral which highlights elevated surfaces, and the surface roughness which increases when the relief is incised by the drainage network. River longitudinal profiles were also analyzed as the drainage network responds quickly to base-level change triggered by external forcing such as tectonics. Anomalies in river profiles (knickpoints and convex segments) were mapped using stream length-gradient (SL) and normalized steepness (ksn) indices. The results provide new insights for understanding the complex evolution of the Jamaican restraining bend. Three main morphotectonic regions were identified in Jamaica: (1) the Blue Mountain-Wagwater unit located at the eastern tip of the island, (2) the Jamaican highlands plateau which covers most of the northern and central areas and (3) the tilted block province located along the southern part of Jamaica. Each region has a specific morphological signature which marks a different stage in the Late Miocene to present evolution of the Jamaican restraining bend. The evolution of the bend is mainly associated with the western propagation of major E-trending strike-slip faults and NW-trending thrusts. In the western and central parts of Jamaica the present-day motion between the Caribbean plate and the Gonâve microplate is broadly distributed along several structures, while in the easternmost part of the island this motion seems to be almost completely accommodated along the Blue Mountain range and the Plantain-Garden Fault.

  13. Transverse Vibrations of Single Bellows Expansion Joint Restrained Against Rotation

    SciTech Connect

    Kameswara, Rao C.; Radhakrishna, M.

    2002-07-01

    The paper presents the results of investigation of transverse vibrations of single bellows expansion joint restrained against rotation on either end. A theoretical model is developed based on the Bernoulli-Euler beam theory and includes added mass of the fluid flowing inside the pipe-bellow-pipe assembly. Neglecting effects of shear and rotary inertia an exact frequency equation is derived for the transverse vibrations of single bellows expansion joint including the effects of end elastic restraints against rotation. Numerical results are presented for an example bellow showing the effects of variation of elastic restraints and internal pressure on the first four modes of vibration. (authors)

  14. Transverse Vibrations of Double Bellows Expansion Joint Restrained Against Rotation

    SciTech Connect

    Kameswara, Rao C.; Radhakrishna, M.

    2002-07-01

    The paper presents the results of investigation of transverse vibrations of double bellows expansion joint restrained against rotation on either end. A theoretical model is developed based on the Bernoulli-Euler beam theory and includes added mass of the fluid flowing inside the pipe-bellow-pipe assembly. Neglecting effect of shear, an exact frequency equation is derived for the transverse vibrations of double bellows expansion joint including the effects of end elastic restraints against rotation. Numerical results are presented for an example bellow showing the effects of variation of elastic restraints and internal pressure on the first two modes of vibration. (authors)

  15. Thermal Behavior of Cylindrical Buckling Restrained Braces at Elevated Temperatures

    PubMed Central

    Talebi, Elnaz; Tahir, Mahmood Md.; Yasreen, Airil

    2014-01-01

    The primary focus of this investigation was to analyze sequentially coupled nonlinear thermal stress, using a three-dimensional model. It was meant to shed light on the behavior of Buckling Restraint Brace (BRB) elements with circular cross section, at elevated temperature. Such bracing systems were comprised of a cylindrical steel core encased in a strong concrete-filled steel hollow casing. A debonding agent was rubbed on the core's surface to avoid shear stress transition to the restraining system. The numerical model was verified by the analytical solutions developed by the other researchers. Performance of BRB system under seismic loading at ambient temperature has been well documented. However, its performance in case of fire has yet to be explored. This study showed that the failure of brace may be attributed to material strength reduction and high compressive forces, both due to temperature rise. Furthermore, limiting temperatures in the linear behavior of steel casing and concrete in BRB element for both numerical and analytical simulations were about 196°C and 225°C, respectively. Finally it is concluded that the performance of BRB at elevated temperatures was the same as that seen at room temperature; that is, the steel core yields prior to the restraining system. PMID:24526915

  16. Thermal behavior of cylindrical buckling restrained braces at elevated temperatures.

    PubMed

    Talebi, Elnaz; Tahir, Mahmood Md; Zahmatkesh, Farshad; Yasreen, Airil; Mirza, Jahangir

    2014-01-01

    The primary focus of this investigation was to analyze sequentially coupled nonlinear thermal stress, using a three-dimensional model. It was meant to shed light on the behavior of Buckling Restraint Brace (BRB) elements with circular cross section, at elevated temperature. Such bracing systems were comprised of a cylindrical steel core encased in a strong concrete-filled steel hollow casing. A debonding agent was rubbed on the core's surface to avoid shear stress transition to the restraining system. The numerical model was verified by the analytical solutions developed by the other researchers. Performance of BRB system under seismic loading at ambient temperature has been well documented. However, its performance in case of fire has yet to be explored. This study showed that the failure of brace may be attributed to material strength reduction and high compressive forces, both due to temperature rise. Furthermore, limiting temperatures in the linear behavior of steel casing and concrete in BRB element for both numerical and analytical simulations were about 196°C and 225°C, respectively. Finally it is concluded that the performance of BRB at elevated temperatures was the same as that seen at room temperature; that is, the steel core yields prior to the restraining system. PMID:24526915

  17. Strategy of restraining ripple error on surface for optical fabrication.

    PubMed

    Wang, Tan; Cheng, Haobo; Feng, Yunpeng; Tam, Honyuen

    2014-09-10

    The influence from the ripple error to the high imaging quality is effectively reduced by restraining the ripple height. A method based on the process parameters and the surface error distribution is designed to suppress the ripple height in this paper. The generating mechanism of the ripple error is analyzed by polishing theory with uniform removal character. The relation between the processing parameters (removal functions, pitch of path, and dwell time) and the ripple error is discussed through simulations. With these, the strategy for diminishing the error is presented. A final process is designed and demonstrated on K9 work-pieces using the optimizing strategy with magnetorheological jet polishing. The form error on the surface is decreased from 0.216λ PV (λ=632.8  nm) and 0.039λ RMS to 0.03λ PV and 0.004λ RMS. And the ripple error is restrained well at the same time, because the ripple height is less than 6 nm on the final surface. Results indicate that these strategies are suitable for high-precision optical manufacturing. PMID:25321688

  18. Spatial learning in the restrained American cockroach Periplaneta americana.

    PubMed

    Kwon, Hyung-Wook; Lent, David D; Strausfeld, Nicholas J

    2004-01-01

    Spatial learning abilities were tested in restrained cockroaches by observing antennal projection responses towards the positions of a learned visual cue perceived monocularly by one eye in the context of a second stimulus provided to the contralateral eye. Memory of the position of the conditioning stimulus relative to the contralateral reference stimulus was tested by altering the relative positions of the two stimuli. Memory of the conditioning stimulus is retained if the angle between the conditioning stimulus and the contralateral reference stimulus is maintained. The results suggest that during learning the insect recognizes spatial relationships between the conditioning stimulus and the contralateral reference stimulus. Possible mechanisms, such as retinotopic matching versus angular matching, are discussed. PMID:14668321

  19. Dynamic modelling of mechanical systems with opposing restrained preloaded stiffnesses

    NASA Astrophysics Data System (ADS)

    Rogers, R. J.; Garland, P.; Oliver, M.

    2004-07-01

    Preloaded springs are used in many mechanical systems such as suspension systems and linkages, as well as household items such as clothing clasps. Usually, the preload has no effect on small amplitude dynamic responses which occur about the mean preloaded position. However if the system has opposing preloaded elastic elements, where unloading is limited by restraints such as central rods which preserve the preload, then the preload has a dramatic effect on a system's dynamic response. When such a system is set into free oscillation, the period of motion steadily decreases as the amplitude diminishes. Until now the authors have not seen this behavior described elsewhere. The present work is motivated by the modelling of joysticks which are used to actuate hydraulic systems in a wide variety of mobile construction and forestry equipment. Their use for long periods of time may lead to repetitive strain injuries in an operator's upper limbs, neck and back. In order to assess the total force required to move a joystick, the stiffness, damping and inertia characteristics must be determined. A mathematical model for joystick dynamics is presented and the effect of restrained spring preloads on the changing period of free vibration is explained. In addition, procedures to estimate the non-symmetric non-linear damping from experimental data are described. By simulating the dynamic response in MATLAB TM, the damping is fine-tuned by comparing the joystick's simulated free oscillation response with its experimental response. Finally, the torque waveform required to perform a simple joystick motion is estimated. The methods developed in this paper could be applied to any lumped-parameter mechanical system where there are opposing restrained preloaded elastic elements.

  20. Altered regional homogeneity and efficient response inhibition in restrained eaters.

    PubMed

    Dong, D; Lei, X; Jackson, T; Wang, Y; Su, Y; Chen, H

    2014-04-25

    Restrained eaters (REs) characterized by less efficient response inhibition are at risk for future onset of binge eating and bulimic pathology. Previous imaging studies investigating REs have been based on task-related functional magnetic resonance imaging (fMRI) and little is known about resting-state neural activity underlying restrained eating. To illuminate this issue, we investigated resting-state fMRI differences between REs (n=22) and unrestrained eaters (UREs) (n=30) using regional homogeneity (ReHo) analysis, which measures the temporal synchronization of spontaneous fluctuations. Samples were equated on body mass index (BMI) and caloric deprivation levels (i.e., 14±2.1h since last evening meal) before undergoing fMRI. Correlation analyses were performed between the ReHo index of identified regions and response inhibition based on stop-signal reaction time (SSRT) within each sample. Compared with UREs, REs showed more ReHo in brain regions associated with food reward (i.e., orbitofrontal cortex (OFC), dorsal-lateral prefrontal cortex (dlPFC)), attention (i.e., lingual gyrus, cuneus, inferior parietal lobule) and somatosensory functioning (i.e., paracentral lobule, anterior insula). In addition, ReHo values for the left dlPFC and left anterior insula, respectively, were negatively and positively correlated with SSRT among REs but not UREs. In concert with previous studies, these results suggest altered local synchronization may help to explain why dieting to maintain or lose weight often fails or increases risk for binge eating among REs. PMID:24513387

  1. Body Dissatisfaction Mediates the Relationship between Self-Esteem and Restrained Eating in Female Undergraduates

    ERIC Educational Resources Information Center

    Gianini, Loren M.; Smith, Jane Ellen

    2008-01-01

    The purpose of the current study was to examine the eating behavior, self-esteem, and social anxiety of restrained and non-restrained eaters exposed to an interpersonal stressor. Sixty female undergraduate students completed questionnaires and took part in a stressor and taste test. Results indicated that self-esteem was not predictive of eating…

  2. Young Adolescent Batterers: A Profile of Restraining Order Defendants in Massachusetts.

    ERIC Educational Resources Information Center

    Cochran, Donald; And Others

    Research indicates a national trend of increasing violence among the juvenile population. This study examines and profiles adolescent restraining order defendants in one state. The study includes all adolescent defendants between the ages of 11 and 17 who had a restraining order issued against them during a 10-month period. This study examined the…

  3. High-restrained eaters only overeat when they are also impulsive.

    PubMed

    Jansen, Anita; Nederkoorn, Chantal; van Baak, Lydia; Keirse, Catharine; Guerrieri, Ramona; Havermans, Remco

    2009-02-01

    Recent work shows that the inability to inhibit basic motor responses (like pressing a button) is related to overeating, weight gain and overweight. In the present study it was tested whether this inability to inhibit motor responses--or impulsivity--can differentiate between successful and unsuccessful restrained eaters. A typical preload and food exposure paradigm was used and it was hypothesized that only the high-restrained eaters that are simultaneously inefficient inhibitors of prepotent motor responses would overeat when confronted with tempting foods. In line with the hypothesis, the data show that overeating follows from an interaction between restraint and impulsivity; high-restrained eaters only overate when they were also impulsive. It is concluded that being restrained per se is not a determinant of overeating. Being a restrained eater only bears the risk of overeating in case of coexisting impulsivity. PMID:19038379

  4. Are temporary restraining orders more likely to be issued when applications mention firearms?

    PubMed

    Vittes, Katherine A; Sorenson, Susan B

    2006-06-01

    Restraining orders, an important legal intervention for victims of domestic violence, have broad potential for injury prevention. Using data from one of the busiest restraining order clinics in the nation, the authors examined 1,354 applicants' descriptions of abuse. Most (89.2%) applicants were issued a restraining order. A total of 16.0% of applicants mentioned a firearm in their descriptions of abuse; doing so was not associated with restraining order issuance. About 1 in 20 applicants, even if issued a restraining order, would not be protected by the federal firearm purchase and possession prohibitions because they had not lived with or had a child with the defendant. However, the proportion of these individuals who report threatened or actual use of firearms against them is similar to that of other applicants. Federal and, when relevant, state law should be modified to include these persons. PMID:16679496

  5. Seismic Energy Demand of Buckling-Restrained Braced Frames

    SciTech Connect

    Choi, Hyunhoon; Kim, Jinkoo

    2008-07-08

    In this study seismic analyses of steel structures were carried out to examine the effect of ground motion characteristics and structural properties on energy demands using 60 earthquake ground motions recorded in different soil conditions, and the results were compared with those of previous works. Analysis results show that ductility ratios and the site conditions have significant influence on input energy. The ratio of hysteretic to input energy is considerably influenced by the ductility ratio and the strong motion duration. It is also observed that as the predominant periods of the input energy spectra are significantly larger than those of acceleration response spectra used in the strength design, the strength demand on a structure designed based on energy should be checked especially in short period structures. For that reason framed structures with buckling-restrained-braces (BRBs) were designed in such a way that all the input energy was dissipated by the hysteretic energy of the BRBs, and the results were compared with those designed by conventional strength-based design procedure.

  6. Folate Deficiency Could Restrain Decidual Angiogenesis in Pregnant Mice

    PubMed Central

    Li, Yanli; Gao, Rufei; Liu, Xueqing; Chen, Xuemei; Liao, Xinggui; Geng, Yanqing; Ding, Yubin; Wang, Yingxiong; He, Junlin

    2015-01-01

    The mechanism of birth defects induced by folate deficiency was focused on mainly in fetal development. Little is known about the effect of folate deficiency on the maternal uterus, especially on decidual angiogenesis after implantation which establishes vessel networks to support embryo development. The aim of this study was to investigate the effects of folate deficiency on decidual angiogenesis. Serum folate levels were measured by electrochemiluminescence. The status of decidual angiogenesis was examined by cluster designation 34 (CD34) immunohistochemistry and the expression of angiogenic factors, including vascular endothelial growth factor A (VEGFA), placental growth factor (PLGF), and VEGF receptor 2 (VEGFR2) were also tested. Serum levels of homocysteine (Hcy), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), progesterone (P4), and estradiol (E2) were detected by Enzyme-linked immunosorbent assay. The folate-deficient mice had a lower folate level and a higher Hcy level. Folate deficiency restrained decidual angiogenesis with significant abnormalities in vascular density and the enlargement and elongation of the vascular sinus. It also showed a reduction in the expressions of VEGFA, VEGFR2, and PLGF. In addition, the serum levels of P4, E2, LH, and PRL were reduced in folate-deficient mice, and the expression of progesterone receptor (PR) and estrogen receptor α (ERα) were abnormal. These results indicated that folate deficiency could impaire decidual angiogenesis and it may be related to the vasculotoxic properties of Hcy and the imbalance of the reproductive hormone. PMID:26247969

  7. Full scale tests of all-steel buckling restrained braces

    NASA Astrophysics Data System (ADS)

    Ma, Ning; Wu, Bin; Li, Hui; Ou, Jinping; Yang, Weibiao

    2009-03-01

    Buckling-restrained braces (BRBs) are widely used seismic response-controlling members with excellent energy dissipation capacity without buckling at design deformation. However, the property of all-steel BRBs with cruciform cross section encased in a square steel tube remains insufficiently studied. In this paper, the properties of this kind of BRBs, which were used in two office buildings in Beijing, were examined by full-scale test. First, initial design was done according to the client's requirement. Then, two full-scale specimens were tested under uniaxial quasi-static cyclic loading. The test results indicate that there should be no welding in yielding portion of the core. Finally, the full-scale subassemblage test was done with an improved BRB and gusset plates installed in a frame. The result shows that the brace exhibited high energy dissipation capacity and stable hysteretic characteristic. According to the results from above tests, some important issues are summarized to provide advices for practical applications.

  8. Seismic Energy Demand of Buckling-Restrained Braced Frames

    NASA Astrophysics Data System (ADS)

    Choi, Hyunhoon; Kim, Jinkoo

    2008-07-01

    In this study seismic analyses of steel structures were carried out to examine the effect of ground motion characteristics and structural properties on energy demands using 60 earthquake ground motions recorded in different soil conditions, and the results were compared with those of previous works. Analysis results show that ductility ratios and the site conditions have significant influence on input energy. The ratio of hysteretic to input energy is considerably influenced by the ductility ratio and the strong motion duration. It is also observed that as the predominant periods of the input energy spectra are significantly larger than those of acceleration response spectra used in the strength design, the strength demand on a structure designed based on energy should be checked especially in short period structures. For that reason framed structures with buckling-restrained-braces (BRBs) were designed in such a way that all the input energy was dissipated by the hysteretic energy of the BRBs, and the results were compared with those designed by conventional strength-based design procedure.

  9. Food Antimicrobials Nanocarriers

    PubMed Central

    Blanco-Padilla, Adriana; Soto, Karen M.; Hernández Iturriaga, Montserrat

    2014-01-01

    Natural food antimicrobials are bioactive compounds that inhibit the growth of microorganisms involved in food spoilage or food-borne illness. However, stability issues result in degradation and loss of antimicrobial activity. Nanoencapsulation allows protection of antimicrobial food agents from unfavorable environmental conditions and incompatibilities. Encapsulation of food antimicrobials control delivery increasing the concentration of the antimicrobials in specific areas and the improvement of passive cellular absorption mechanisms resulted in higher antimicrobial activity. This paper reviews the present state of the art of the nanostructures used as food antimicrobial carriers including nanoemulsions, nanoliposomes, nanoparticles, and nanofibers. PMID:24995363

  10. Main Factors to Restrain the Development of Library and Their Countermeasures

    ERIC Educational Resources Information Center

    Jiang, Qian; Zhang, Yonghong

    2011-01-01

    From many aspects such as the resource construction, the talent group, and the mechanism and system, main factors to restrain the development of college library are analyzed, and corresponding countermeasures are proposed in this article.

  11. Restraining Loose Equipment Aboard the International Space Station: The Payload Equipment Restraint System

    NASA Technical Reports Server (NTRS)

    Smith, Kenneth A.; Reynolds, D. W.; Vanhooser, Teresa (Technical Monitor)

    2002-01-01

    As the International Space Station (ISS) grows, so do the supplies and equipment needed to support its daily operations. Each day many items must be unstowed and relocated to various worksites so they are readily available to the crew. Due to the lack of gravity, these items may become loose and float away if not restrained. The Payload Equipment Restraint System was developed to meet the new and unique challenge of restrain no loose equipment aboard the ISS.

  12. Restrained eating predicts effortful self-control as indicated by heart rate variability during food exposure.

    PubMed

    Geisler, Fay C M; Kleinfeldt, Anne; Kubiak, Thomas

    2016-01-01

    When confronted with food, restrained eaters have to inhibit the pursuit of the short-term goal of enjoying their food for the sake of the long-term goal of controlling their weight. Thus, restrained eating creates a self-control situation. In the present study we investigated the initiation of effortful self-control by food cues in accordance with the level of restrained eating. We expected that a preceding act of self-control would moderate the association between restrained eating and effortful self-control initiated by food cues. Participants (N=111) were randomly assigned to a task requiring self-control or a task not requiring self-control. Subsequently, participants were exposed to palatable food, and effortful self-control was measured via heart rate variability (HRV). Restrained eating was associated with enhanced HRV during food exposure after exercising self-control but not after not exercising self-control. The results indicate that maintaining dieting goals results in food cues initiating effortful self-control after a preceding act of self-control. We suggest considering the effect of acts of self-control when modeling the initial steps on the path from food cues to unsuccessful restrained eating. PMID:26500202

  13. Antimicrobial peptides.

    PubMed

    Zhang, Ling-Juan; Gallo, Richard L

    2016-01-11

    Antimicrobial peptides and proteins (AMPs) are a diverse class of naturally occurring molecules that are produced as a first line of defense by all multicellular organisms. These proteins can have broad activity to directly kill bacteria, yeasts, fungi, viruses and even cancer cells. Insects and plants primarily deploy AMPs as an antibiotic to protect against potential pathogenic microbes, but microbes also produce AMPs to defend their environmental niche. In higher eukaryotic organisms, AMPs can also be referred to as 'host defense peptides', emphasizing their additional immunomodulatory activities. These activities are diverse, specific to the type of AMP, and include a variety of cytokine and growth factor-like effects that are relevant to normal immune homeostasis. In some instances, the inappropriate expression of AMPs can also induce autoimmune diseases, thus further highlighting the importance of understanding these molecules and their complex activities. This Primer will provide an update of our current understanding of AMPs. PMID:26766224

  14. Antimicrobial Drugs in Fighting against Antimicrobial Resistance

    PubMed Central

    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.e., mutation and horizontal gene transfer of resistance determinants), the community level resistance (i.e., bilofilms and persisters) is also an issue causing antimicrobial therapy difficulties. Therefore, anti-resistance and antibiofilm strategies have currently become research hotspot to combat antimicrobial resistance. Although metallic nanoparticles can both kill bacteria and inhibit biofilm formation, the toxicity is still a big challenge for their clinical applications. In conclusion, rational use of the existing antimicrobials and combinational use of new strategies fighting against antimicrobial resistance are powerful warranties to preserve potent antimicrobial drugs for both humans and animals. PMID:27092125

  15. Acquired differences in brain responses among monozygotic twins discordant for restrained eating.

    PubMed

    Schur, Ellen A; Kleinhans, Natalia M; Goldberg, Jack; Buchwald, Dedra S; Polivy, Janet; Del Parigi, Angelo; Maravilla, Kenneth R

    2012-01-18

    We studied whether self-reported intent to exert cognitive control over eating was associated with differences in brain response to food cues, independent of genetic background. Subjects were ten pairs of identical twins in which one twin was a restrained eater and the co-twin was unrestrained, as classified by the Herman and Polivy Restraint Scale. Before and after ingestion of a milkshake, we used functional magnetic resonance imaging to measure brain response to photographs of objects, "fattening" food, and "non-fattening" food. At baseline, restrained eaters had greater activation in the left amygdala and the right thalamus in response to fattening food cues than did their unrestrained co-twins. When restrained eaters drank a milkshake, activation in response to fattening food photographs decreased across multiple brain areas, whereas activation induced by non-fattening food photographs increased. As compared to their unrestrained co-twins, restrained eaters who drank a milkshake had greater decreases in activation by fattening food images in the left amygdala and occipital lobe, and greater increases in activation by non-fattening food images in the medial orbitofrontal cortex. Because of the discordant monozygotic twin study design, the findings provide a rigorous level of support for the hypothesis that adopting an intention to restrain eating alters brain response to food cues. PMID:21945867

  16. Antimicrobial Treatments and Efficacy

    EPA Science Inventory

    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...

  17. Animation of Antimicrobial Resistance

    MedlinePlus

    ... major obstacles to understanding the issue of antimicrobial resistance is that the subject material appears abstract and is complex. This video was designed to make the concept of antimicrobial resistance more real and understandable to veterinarians, livestock producers, ...

  18. Disarming batterers through restraining orders: the promise and the reality in California.

    PubMed

    Seave, Paul L

    2006-06-01

    Laws that prohibit persons under a domestic violence restraining order from purchasing or possessing a firearm are a primary way to keep guns out of the hands of batterers. In July 2005, the California Attorney General's Task Force on the Local Criminal Justice Response to Domestic Violence issued a report called Keeping the Promise: Victim Safety and Batterer Accountability. The report focused, in part, on the extent to which California's domestic violence restraining order system succeeds in disarming batterers. Restraining orders are the principal means by which the criminal justice system can accomplish this objective. The Task Force found that criminal justice agencies and the courts performed poorly in this area. The report strongly recommended that a more strategic, collaborative use of laws already on the books could significantly improve performance, without much additional expense. What follows is a summary of those finding and recommendations. PMID:16679495

  19. That swimsuit becomes you: sex differences in self-objectification, restrained eating, and math performance.

    PubMed

    Fredrickson, B L; Roberts, T A; Noll, S M; Quinn, D M; Twenge, J M

    1998-07-01

    Objectification theory (B. L. Fredrickson & T. Roberts, 1997) posits that American culture socializes women to adopt observers' perspectives on their physical selves. This self-objectification is hypothesized to (a) produce body shame, which in turn leads to restrained eating, and (b) consume attentional resources, which is manifested in diminished mental performance. Two experiments manipulated self-objectification by having participants try on a swimsuit or a sweater. Experiment 1 tested 72 women and found that self-objectification increased body shame, which in turn predicted restrained eating. Experiment 2 tested 42 women and 40 men and found that these effects on body shame and restrained eating replicated for women only. Additionally, self-objectification diminished math performance for women only. Discussion centers on the causes and consequences of objectifying women's bodies. PMID:9686464

  20. Buckling analysis of fully anisotropic plates containing cutouts and elastically restrained edges

    NASA Technical Reports Server (NTRS)

    Jones, Kevin M.; Klang, Eric C.

    1992-01-01

    An analysis is developed which combines the Ritz and collocation methods for the stability solution of an anisotropic plate with a cutout and elastically restrained edges. Results are presented which agree closely with experiment for isotropic and orthotropic materials. Results are also given for restrained anisotropic plates with circular holes loaded in compression and shear. Difference is noted in the critical buckling loads between displacement and stress loaded panels as hole size is increased. Clamping is also seen to affect the trends in buckling associated with hole size.

  1. Intraoperative brachial plexus injury during emergence following movement with arms restrained: a preventable complication?

    PubMed Central

    Chandler, Mark H; DiMatteo, Laura; Hasenboehler, Erik A; Temple, Michael

    2007-01-01

    Background Despite considerable analysis and preventive strategies, brachial plexus injuries remain fairly common in the perioperative setting. These injuries range from brief periods of numbness or discomfort in the immediate postoperative period to, in rare cases, profound, prolonged losses of sensation and function. We present a case of an orthopedic surgery patient who suffered a brachial plexus injury while under anesthesia after trying to sit upright with his arms restrained. Case presentation After the uneventful placement of an intramedullary tibial nail, an 18 year old patient tried to sit upright with his arms restrained while still under the influence of anesthesia. In the immediate postoperative period, the patient complained of a profound loss of sensation in his left arm and an inability to flex his left elbow, suppinate his arm, or abduct and rotate his shoulder. Neurological examination and subsequent studies revealed a C5-6 brachial plexus injury. The patient underwent range of motion physical therapy and, over the next three months, regained the full function and sensation of his left arm. Conclusion Restraining arms during general anesthesia to prevent injury remains a wise practice. However, to avoid injuring the brachial plexus while the arms are restrained, extra caution must be used to prevent unexpected patient movement and to ensure gentle emergence. PMID:18271944

  2. Disarming Batterers through Restraining Orders: The Promise and the Reality in California

    ERIC Educational Resources Information Center

    Seave, Paul L.

    2006-01-01

    Laws that prohibit persons under a domestic violence restraining order from purchasing or possessing a firearm are a primary way to keep guns out of the hands of batterers. In July 2005, the California Attorney General's Task Force on the Local Criminal Justice Response to Domestic Violence issued a report called Keeping the Promise: Victim Safety…

  3. USDA Data on Antimicrobial Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimicrobial susceptibility testing remains an important tool as investigators devise ways to arrest the development of antimicrobial resistance, particularly in food borne bacteria. In 1996, the Food and Drug Administration (FDA) initiated the National Antimicrobial Resistance Monitoring System -...

  4. Antimicrobial (Drug) Resistance

    MedlinePlus

    ... Antimicrobial (Drug) Resistance Antibiotic-Resistant Mycobacterium tuberculosis (TB) Methicillin-Resistant Staphylococcus aureus (MRSA) Vancomycin-Resistant Enterococci (VRE) Multidrug-Resistant Neisseria ...

  5. Reworking of structural inheritance at strike-slip restraining-bends: templates from sandbox analogue models

    NASA Astrophysics Data System (ADS)

    Nestola, Yago; Storti, Fabrizio; Cavozzi, Cristian; Magistroni, Corrado; Meda, Marco; Piero Righetti, Fabrizio

    2016-04-01

    Structural inheritance plays a fundamental role during crustal deformation because pre-existing fault and shear zones typically provide weakness zone suitable to fail again when affected by a new regional stress field. Re-activation of structural inheritance is expected to unavoidably increase the complexity of structural architectures, whose geometric and kinematic patterns can significantly deviate from what expected in newly deformed crustal sectors. Availability of templates from analogue models can provide a very effective tool to help unraveling such a structural complexity. For this purpose, we simulated the reworking of a set of basement hosted pre-existing fault zones at strike-slip restraining fault bends. In the models, the mechanical stratigraphy consists of a basement, made of a mixture of dry kaolin and sand to slightly increase cohesion, and a sedimentary cover made by pure dry sand. Inherited fault zones are confined to the basement and coated by a thin veneer of silicone putty. In the experimental programme, the geometry of the left-lateral restraining bend is maintained the same, with a bending angle of 30° of the restraining fault segment. The strike of the inherited fault zones, measured counterclockwise with respect to that of the master strike-slip fault zone outside the restraining bend, was 0°, 30°, and 60° in different experiments, respectively. An end member experiment without inheritance was also run for comparison. Our experimental results show that the angle that the inherited fault zones make with the restraining bend plays a fundamental role in governing the deformation pattern. When structural inheritance is near parallel to the master strike-slip fault zone, synthetic shears form and severely compartmentalize the transpressional pop-up anticline growing on top of the restraining bend. Fault-bounded blocks undergo sinistral escape during transpression. On the other hand, when structural inheritance makes a high angle to the

  6. Antimicrobial Peptides in 2014

    PubMed Central

    Wang, Guangshun; Mishra, Biswajit; Lau, Kyle; Lushnikova, Tamara; Golla, Radha; Wang, Xiuqing

    2015-01-01

    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. PMID:25806720

  7. Antimicrobial use: Alternatives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For over fifty years, antimicrobials have been used in food animal production to maintain animal health and to increase productivity. The resulting increase in antimicrobial resistance among enteric bacteria has created two principal concerns: 1) the prevalence of drug-resistant pathogens leaves th...

  8. Antimicrobial peptides in 2014.

    PubMed

    Wang, Guangshun; Mishra, Biswajit; Lau, Kyle; Lushnikova, Tamara; Golla, Radha; Wang, Xiuqing

    2015-01-01

    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. PMID:25806720

  9. Selective attention to food and body shape words in dieters and restrained nondieters.

    PubMed

    Green, M W; Rogers, P J

    1993-12-01

    The current study investigated the presence of an attentional bias towards the processing of body shape and food-related material amongst noneating disordered women. Subjects carried out a computer-based Stroop color-naming task in which they had to name the colors of food-related words, body shape-related words, and two sets of matched neutral words. Significant color-naming disruptions of both food and body shape-related material were found for highly restrained eaters, irrespective of whether they were currently dieting. There were no reliable differences in color-naming times found for low to medium restrained eaters. Procedural differences probably account for the failure of previous studies to reveal such effects in nonclinical groups. PMID:8293036

  10. Stromal elements act to restrain, rather than support, pancreatic ductal adenocarcinoma

    PubMed Central

    Rhim, Andrew D.; Oberstein, Paul E.; Thomas, Dafydd H.; Mirek, Emily T.; Palermo, Carmine F.; Sastra, Steve A.; Dekleva, Erin N.; Saunders, Tyler; Becerra, Claudia P; Tattersall, Ian W.; Westphalen, C. Benedikt; Kitajewski, Jan; Fernandez-Barrena, Maite G.; Fernandez-Zapico, Martin E.; Iacobuzzio-Donahue, Christine; Olive, Kenneth P.; Stanger, Ben Z.

    2014-01-01

    SUMMARY Sonic hedgehog (Shh), a soluble ligand overexpres sed by neoplastic cells in pancreatic ductal adenocarcinoma (PDAC), drives formation of a fibroblast-rich desmoplastic stroma. To better understand its role in malignant progression, we deleted Shh in a well-defined mouse model of PDAC. As predicted, Shh-deficient tumors had reduced stromal content. Surprisingly, such tumors were more aggressive and exhibited undifferentiated histology, increased vascularity, and heightened proliferation – features that were fully recapitulated in control mice treated with a Smoothened inhibitor. Furthermore, administration of VEGFR blocking antibody selectively improved survival of Shh-deficient tumors, indicating that Hedgehog-driven stroma suppresses tumor growth in part by restraining tumor angiogenesis. Together, these data demonstrate that some components of the tumor stroma can act to restrain tumor growth. PMID:24856585

  11. Relationship of Dieting and Restrained Eating to Self-Reported Caloric Intake in Female College Freshmen

    PubMed Central

    Goldstein, Stephanie P.; Katterman, Shawn N.; Lowe, Michael R.

    2012-01-01

    Evidence indicates that restrained eaters do not eat less than unrestrained eaters in the natural environment. However, no study has examined caloric intake in those who are currently dieting to lose, or avoid gaining, weight. The current study examined caloric intake using 24-hour food recalls among individuals dieting to lose weight, dieting to avoid weight gain, restrained nondieters, and unrestrained nondieters. Participants were 246 female college students participating in a weight gain prevention trial. The predicted significant difference in caloric intake across the four groups was found for beverage but not for food intake. Results reinforce past literature indicating that dieting/restraint status does not reflect hypo-caloric intake in naturalistic settings. PMID:23557829

  12. Investigation on frictional characteristics and drawbead restraining force of steel with/without coating

    NASA Astrophysics Data System (ADS)

    Chen, Lianfeng; Zheng, Tianran; Chen, Qing; Zhang, Jun

    2013-12-01

    Advanced high strength steels (AHSS) are used more and more in automotive industry for increasing crashworthiness and weight reduction. Improving metal flow and reduce friction are important to forming the part and decrease part reject rates of AHSS. The present study focused on friction characteristics and drawbead restraining force of Dual Phase (DP) steels with or without coating, such as DP980, DP780, DP590, DP780+Z, DP780+ZF, DP590+Z, using experimental approach. The effect of material properties, temperature, sliding velocity, surface roughness, dry and lubricant on friction behavior of DP steels is investigated. The contrast of DP steels with mild IF steel is carried out. The restraining force draw through different radius of drawbead is evaluated. This study is benefit to the set up of technique parameters during sheet metal forming simulation.

  13. Relationship of dieting and restrained eating to self-reported caloric intake in female college freshmen.

    PubMed

    Goldstein, Stephanie P; Katterman, Shawn N; Lowe, Michael R

    2013-04-01

    Evidence indicates that restrained eaters do not eat less than unrestrained eaters in the natural environment. However, no study has examined caloric intake in those who are currently dieting to lose, or avoid gaining, weight. The current study examined caloric intake using 24-hour food recalls among individuals dieting to lose weight, dieting to avoid weight gain, restrained nondieters, and unrestrained nondieters. Participants were 246 female college students participating in a weight gain prevention trial. The predicted significant difference in caloric intake across the four groups was found for beverage but not for food intake. Results reinforce past literature indicating that dieting/restraint status does not reflect hypo-caloric intake in naturalistic settings. PMID:23557829

  14. Alternative Antimicrobial Approach: Nano-Antimicrobial Materials

    PubMed Central

    Beyth, Nurit; Houri-Haddad, Yael; Domb, Avi; Khan, Wahid; Hazan, Ronen

    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 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. PMID:25861355

  15. Absolute Binding Free Energy Calculations Using Molecular Dynamics Simulations with Restraining Potentials

    PubMed Central

    Wang, Jiyao; Deng, Yuqing; Roux, Benoît

    2006-01-01

    The absolute (standard) binding free energy of eight FK506-related ligands to FKBP12 is calculated using free energy perturbation molecular dynamics (FEP/MD) simulations with explicit solvent. A number of features are implemented to improve the accuracy and enhance the convergence of the calculations. First, the absolute binding free energy is decomposed into sequential steps during which the ligand-surrounding interactions as well as various biasing potentials restraining the translation, orientation, and conformation of the ligand are turned “on” and “off.” Second, sampling of the ligand conformation is enforced by a restraining potential based on the root mean-square deviation relative to the bound state conformation. The effect of all the restraining potentials is rigorously unbiased, and it is shown explicitly that the final results are independent of all artificial restraints. Third, the repulsive and dispersive free energy contribution arising from the Lennard-Jones interactions of the ligand with its surrounding (protein and solvent) is calculated using the Weeks-Chandler-Andersen separation. This separation also improves convergence of the FEP/MD calculations. Fourth, to decrease the computational cost, only a small number of atoms in the vicinity of the binding site are simulated explicitly, while all the influence of the remaining atoms is incorporated implicitly using the generalized solvent boundary potential (GSBP) method. With GSBP, the size of the simulated FKBP12/ligand systems is significantly reduced, from ∼25,000 to 2500. The computations are very efficient and the statistical error is small (∼1 kcal/mol). The calculated binding free energies are generally in good agreement with available experimental data and previous calculations (within ∼2 kcal/mol). The present results indicate that a strategy based on FEP/MD simulations of a reduced GSBP atomic model sampled with conformational, translational, and orientational restraining

  16. Peak and end effects on remembered enjoyment of eating in low and high restrained eaters.

    PubMed

    Robinson, Eric; Blissett, Jackie; Higgs, Suzanne

    2011-08-01

    Memory is likely to be important in food choice because many food likes and dislikes are learnt. Evidence suggests that the final few moments of an experience ('end effect') and the most intense moments of an experience ('peak effect') have a disproportionately large influence on hedonic memories. In Study 1 we examined whether the end effect bias is applicable to remembered enjoyment of a food and whether this holds true for restrained and unrestrained eaters. One hundred and four participants ate the same yoghurt but half the participants experienced a pleasant end and half a bland end (control condition). Although both the 'pleasant ending' and control group had a similar online enjoyment of the yoghurt, unrestrained eaters who experienced a pleasant end remembered it to have been significantly more enjoyable than those in the control condition. No end effect was observed for restrained eaters. In Study 2 we examined predictors of remembered enjoyment of a multi-item meal. Forty-six participants consumed and rated 5 buffet style food items as part of a lunch time meal. For unrestrained eaters, remembered enjoyment of the meal was only predicted by 'peak' online enjoyment of the most liked item. Participant's enjoyment of the first, last and least liked items did not predict remembered enjoyment. For restrained eaters, remembered enjoyment was not predicted by any of the four predictor variables. These results suggest that for unrestrained eaters key moments in eating experiences have disproportionately large influence on remembered enjoyment of eating. PMID:21570432

  17. Experimental Tests of a Real Building Seismically Retrofitted by Special Buckling-Restrained Braces

    SciTech Connect

    D'Aniello, Mario; Della Corte, Gaetano; Mazzolani, Federico M.

    2008-07-08

    Buckling Restrained Braces (BRBs), differently from conventional braces, do not exhibit appreciable difference between the tensile and compression capacity and no strength degradation of brace capacity under compressive and cyclic loading. Since lateral and local buckling behaviour modes are restrained, large inelastic capacities are attainable. Hence, BRBs may represent an efficient and reliable solution for reducing the seismic vulnerability of buildings. Results of experimental tests on the response of a real two-story reinforced concrete (RC) building equipped with BRBs are presented and discussed. The considered BRBs are a special 'only-steel' version of the more common 'unbonded braces'. In particular, two different BRBs have been tested. Both of them are detachable 'only-steel' devices, consisting in a rectangular steel plate and a restraining steel sleeve. The latter is composed by two omega shapes which are bolted together. The main characteristic of the braces consists in the possibility to hide them within the space between the facing and the backing of masonry infill walls commonly used for RC buildings.

  18. 3-D Coupled FE Analysis and Experimental Validation of Restrained Welding to Control Angular Distortion

    NASA Astrophysics Data System (ADS)

    Damale, A. V.; Nandurkar, K. N.

    2012-10-01

    Welding induced distortion is one of the critical defects in the welded structures. Angular distortion is most pronounced which badly affects the welded structures. Non-uniform heating during welding develops this angular distortion. Various methods are available to control/minimize the welding distortions. One of the methods available to control this distortion is restraining, in which clamping pressure is applied on the deforming edges of the plates. In the present study, a 3-dimensional coupled transient thermal analysis is done for simulating the restraining phenomenon of welding. The developed transient thermal heat source was used to simulate the arc welding phenomenon. The element birth and death technique was used for simulating filler material deposition. Thermal model was verified by comparing the macrograph of Finite Element Analysis (FEA) model and the weld and verification of structural model was done by comparing the measured and predicted angular distortions. Experimental and Finite Element (FE) analysis is done for both conventional welding and welding under restraining pressure. Transient thermal and non-linear structural analyses were carried out in order to predict angular distortions. The Finite Element Method analysis and experimental verification is done for manual metal arc welding process.

  19. Experimental Tests of a Real Building Seismically Retrofitted by Special Buckling-Restrained Braces

    NASA Astrophysics Data System (ADS)

    D'Aniello, Mario; Corte, Gaetano Della; Mazzolani, Federico M.

    2008-07-01

    Buckling Restrained Braces (BRBs), differently from conventional braces, do not exhibit appreciable difference between the tensile and compression capacity and no strength degradation of brace capacity under compressive and cyclic loading. Since lateral and local buckling behaviour modes are restrained, large inelastic capacities are attainable. Hence, BRBs may represent an efficient and reliable solution for reducing the seismic vulnerability of buildings. Results of experimental tests on the response of a real two-story reinforced concrete (RC) building equipped with BRBs are presented and discussed. The considered BRBs are a special `only-steel' version of the more common `unbonded braces'. In particular, two different BRBs have been tested. Both of them are detachable "only-steel" devices, consisting in a rectangular steel plate and a restraining steel sleeve. The latter is composed by two omega shapes which are bolted together. The main characteristic of the braces consists in the possibility to hide them within the space between the facing and the backing of masonry infill walls commonly used for RC buildings.

  20. Antimicrobial Peptides in Reptiles

    PubMed Central

    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

  1. Fast Disinfecting Antimicrobial Surfaces

    PubMed Central

    Madkour, Ahmad E.; Dabkowski, Jeffery M.; Nüsslein, Klaus; Tew, Gregory N.

    2013-01-01

    Silicon wafers and glass surfaces were functionalized with facially amphiphilic antimicrobial copolymers using the “grafting from” technique. Surface initiated atom transfer radical polymerization (ATRP) was used to grow poly(butylmethacrylate)-co-poly(Boc-aminoethyl methacrylate) from the surfaces. Upon Boc-deprotection, these surfaces became highly antimicrobial and killed S. aureus and E. coli 100% in less than 5 min. The molecular weight and grafting density of the polymer were controlled by varying the polymerization time and initiator surface density. Antimicrobial studies showed that the killing efficiency of these surfaces was independent of polymer layer thickness or grafting density within the range of surfaces studied. PMID:19177651

  2. Antimicrobial activity of isopteropodine.

    PubMed

    García, Rubén; Cayunao, Cesia; Bocic, Ronny; Backhouse, Nadine; Delporte, Carle; Zaldivar, Mercedes; Erazo, Silvia

    2005-01-01

    Bioassay-directed fractionation for the determination of antimicrobial activity of Uncaria tomentosa, has led to the isolation of isopteropodine (0.3%), a known Uncaria pentacyclic oxindol alkaloid that exhibited antibacterial activity against Gram positive bacteria. PMID:16042336

  3. Novel antimicrobial textiles

    NASA Astrophysics Data System (ADS)

    Cho, Unchin

    2003-10-01

    Many microorganisms can survive, and perhaps proliferate on textiles, generating adverse effects such as: disease transmission, odor generation, pH changes, staining, discoloration and loss of performance. These adverse effects may threaten users' health, deteriorate textile properties and degrade service quality. It may, therefore, be desirable to incorporate antimicrobials on textiles for controlling the growth of microorganisms. This dissertation focuses on the development of antimicrobial fibers and fabrics by integration of antimicrobials with these textiles. The applications of hydantoin-based halamines were mainly investigated in the research. The typical process is that hydantoin containing compounds are grafted onto textiles and transformed to halamine by chlorination. Hydantoin-based halamines are usually chloramines that release chlorine (Cl+) via cleavage of the -NCl functional group which attacks and kills microbes. The antimicrobial behavior is rechargeable many times by rinsing the fiber or fabric with chlorine-containing solution. Some quaternary ammonium type antimicrobials were also investigated in this research. The choice of integrating techniques is dependant on both the textile and antimicrobial compounds. In this dissertation, the nine approaches were studied for incorporating antimicrobial with various textiles: (1) co-extrusion of fibers with halamine precursor additive; (2) grafting of the quaternary ammonium compounds onto ethylene-co-acrylic acid fiber for creating quaternary ammonium type antimicrobial fiber; (3) entrapment of the additives in thermally bonded bicomponent nonwoven fabrics; (4) attaching antimicrobial additives to surfaces with latex adhesive coating; (5) grafting of antimicrobial compounds onto rubber latex via UV exposure; (6) reaction of halamine with needle-punched melamine formaldehyde nonwoven fabric and laminates; (7) coating melamine resin onto tent fabrics and laminates; (8) synthesis of super absorbent polymer

  4. Antimicrobial Compounds in Tears

    PubMed Central

    McDermott, Alison M.

    2013-01-01

    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. PMID:23880529

  5. Denali in a box: analog experiments modeled after a natural setting provide insight on gentle restraining bend deformation

    NASA Astrophysics Data System (ADS)

    Fendick, Anne; Bemis, Sean; Toeneboehn, Kevin; Cooke, Michele; Benowitz, Jeff

    2016-04-01

    Despite restraining bends along strike-slip faults creating zones of focused uplift, the relative contributions from parameters such as fault geometry and scale, obliquity, rheological contrasts, and deformation rates are not well-constrained. Similarities between simple analog models (conducted with homogenous materials) and natural restraining bend systems (typically associated with heterogeneous crust) suggest that there are first-order controls on restraining bend deformation that operate independent of heterogeneity in the upper crust. To investigate these controls we examine the Mount McKinley restraining bend (MMRB) of the Denali fault system in south-central Alaska. The MMRB is associated with an ~18 degree bend in the Denali fault and exhibits strongly asymmetric topography and rock uplift. The viscous relaxation time and the ratio of crustal thickness to the restraining bend stepover distance are scaled within the analog model to that of the MMRB. We compare uplift patterns, localization of deformation, formation of new faults, and displacement fields for the model set up and the natural bend to understand the influence of different variables on the overall system to determine what controls the deformation. As shown in previous analog model studies, asymmetric topography characteristically forms with restraining bend angles of <20°. In our model, a continuous, through-going fault within the restraining bend accompanies a narrow zone of deformation on one side of the bend and a broader zone of deformation the opposite side. However, the active thrust faults of the MMRB are purely dip-slip, whereas the thrust faults formed in the model appear to be oblique-slip. The geometry and slip rates of active faults in the MMRB, as well as preliminary thermochronometric data, suggest that the restraining bend itself is migrating relative to previously deformed deposits. Conventional understanding of restraining bends is that fixed bends produce the highest

  6. A comparative study of pi-arene-bridged lanthanum arylamide and aryloxide dimers. Solution behavior, exchange mechanisms, and X-ray crystal structures of La2(NH-2,6-iPr2C6H3)6, La(NH-2,6-iPr2C6H3)3(THF)3, and La(NH-2,6-iPr2C6H3)3(py)2.

    PubMed

    Giesbrecht, Garth R; Gordon, John C; Clark, David L; Hay, P Jeffrey; Scott, Brian L; Tait, C Drew

    2004-05-26

    Reaction of 3 equiv of 2,6-diisopropylaniline with La[N(SiMe(3))(2)](3) produces the dimeric species La(2)(NHAr)(6) (1). X-ray crystallography reveals a centrosymmetric structure, where the dimeric unit is bridged by intermolecular eta(6)-arene interactions of a unique arylamide ligand attached to an adjacent metal center. Exposure of 1 to THF results in formation of the monomeric tris-THF adduct La(NHAr)(3)(THF)(3) (2), which was shown by X-ray crystallography to maintain a fac-octahedral structure in the solid state. (1)H NMR spectroscopy illustrates that the binding of THF to 1 to form 2 is reversible and removal of THF under vacuum regenerates dimeric 1. Addition of pyridine to 1 yields the monomeric bis-pyridine adduct La(NHAr)(3)(py)(2) (3), which exhibits a distorted trigonal-bipyramidal La metal center. Solution (1)H NMR, IR, and Raman spectroscopy indicate that the pi-arene-bridged dimeric structure of 1 is maintained in solution. Variable-temperature (1)H NMR spectroscopic investigations of 1 are consistent with a monomer-dimer equilibrium at elevated temperature. In contrast, variable-temperature (1)H NMR spectroscopic investigations of the aryloxide analogue La(2)(OAr)(6) (4) show that the bridging and terminal aryloxide groups exchange by a mechanism in which the dimeric nature of the compound is retained. Density functional theory (DFT) calculations were carried out on model compounds La(2)(OC(6)H(5))(6), La(2)(NHC(6)H(5))(6), and (C(6)H(5)R)La(XC(6)H(5))(3), where X = O or NH and R = H, OH, or NH(2). The formation of eta(6)-arene interactions is energetically favored over monomeric LaX(3) (X = OPh or NHPh) with the aryloxide pi-arene interaction being stronger than the arylamide pi-arene interaction. Calculation of vibrational frequencies reveals the origin of the observed IR spectral behavior of both La(2)(OC(6)H(5))(6) and La(2)(NHC(6)H(5))(6), with the higher energy nu(C=C) stretch due to terminal ligands and the lower energy stretch associated

  7. Distributed and Localized Deformation Along the Lebanese Restraining Bend from Geomorphic Observations and Modeling

    NASA Astrophysics Data System (ADS)

    Goren, L.; Castelltort, S.; Klinger, Y.

    2014-12-01

    The Dead Sea Fault System changes its orientation across Lebanon and forms a restraining bend. The oblique deformation along the Lebanese restraining bend is characterized by a complex suite of tectonic structures, among which, the Yammouneh Fault (YF), is believed to be the main strand that relays deformation from the southern section to the northern section of the Dead Sea Fault System. However, uncertainties regarding slip rates and strain partitioning in Lebanon still prevail. Here, we use morphometric analysis together with analytical and numerical models to constrain rates and modes of distributed and localized deformation along the Lebanese restraining bend.The rivers that drain the western flank of Mount Lebanon show a consistent counterclockwise rotation with respect to an expected orogen perpendicular orientation. Moreover, a pattern of divide disequilibrium in between these rivers emerges from an application of the χ mapping technique, which aims at estimating the degree of geometrical and topological disequilibrium in river networks. These geometrical patterns are compatible with simulation results using a landscape evolution model, which imposes a distributed velocity field along a domain that represents the western flank of Mount Lebanon. We further develop an analytical model that relates the river orientation to a set of kinematic parameters that represents a combined pure and simple shear strain field, and we find the parameters that best explain the present orientation of the western Lebanon rivers. Our results indicate that distributed deformation to the west of the YF takes as much as 30% of the relative Arabia-Sinai plate velocity since the late Miocene, and that the average slip rate along the YF during the same time interval has been 3.8-4.4 mm/yr. The theoretical model can further explain the inferred rotation from Paleomagnetic measurements.

  8. Vanillin restrains non-enzymatic glycation and aggregation of albumin by chemical chaperone like function.

    PubMed

    Awasthi, Saurabh; Saraswathi, N T

    2016-06-01

    Vanillin a major component of vanilla bean extract is commonly used a natural flavoring agent. Glycation is known to induce aggregation and fibrillation of globular proteins such as albumin, hemoglobin. Here we report the inhibitory potential of vanillin toward early and advanced glycation modification and amyloid like aggregation of albumin based on the determination of both early and advanced glycation and conformational changes in albumin using circular dichroism. Inhibition of aggregation and fibrillation of albumin was determined based on amyloid specific dyes i.e., Congo red and Thioflavin T and microscopic imaging. It was evident that vanillin restrains glycation of albumin and exhibits protective effect toward its native conformation. PMID:26893056

  9. Safeguarding the integrity of science communication by restraining 'rational cheating' in peer review.

    PubMed

    Barroga, Edward F

    2014-11-01

    Peer review is the pillar of the integrity of science communication. It is often beset with flaws as well as accusations of unreliability and lack of predictive validity. 'Rational cheating' by reviewers is a threat to the validity of peer review. It may diminish the value of good papers by unfavourable appraisals of the reviewers whose own works have lower scientific merits. This article analyzes the mechanics and defects of peer review and focuses on rational cheating in peer review, its implications, and options to restrain it. PMID:25408573

  10. DisVis: quantifying and visualizing accessible interaction space of distance-restrained biomolecular complexes

    PubMed Central

    van Zundert, G.C.P.; Bonvin, A.M.J.J.

    2015-01-01

    Summary: We present DisVis, a Python package and command line tool to calculate the reduced accessible interaction space of distance-restrained binary protein complexes, allowing for direct visualization and quantification of the information content of the distance restraints. The approach is general and can also be used as a knowledge-based distance energy term in FFT-based docking directly during the sampling stage. Availability and implementation: The source code with documentation is freely available from https://github.com/haddocking/disvis. Contact: a.m.j.j.bonvin@uu.nl Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26026169

  11. Column strength of tubes elastically restrained against rotation at the ends

    NASA Technical Reports Server (NTRS)

    Osgood, William R

    1938-01-01

    Report presents the results of a study made of the effects of known end restraint on commercially available round and streamline tubing of chromium-molybdenum steel, duralumin, stainless steel, and heat-treated chromium-molybdenum steel; and a more accurate method than any previously available, but still a practical method, was developed for designing compression members in riveted or welded structures, particularly aircraft. Two hundred specimens were tested as short, medium-length, and long columns with freely supported ends or elastically restrained ends. Tensile and compressive tests were made on each piece of original tubing from which column specimens were cut.

  12. Neotectonics of Hispaniola - Plate motion, sedimentation, and seismicity at a restraining bend

    NASA Technical Reports Server (NTRS)

    Mann, P.; Matumoto, T.; Burke, K.

    1984-01-01

    The question as to the extent to which earthquake mechanisms define plate motion is addressed in view of the pattern of Neogene faulting, volcanism, and sedimentation in Hispaniola. The structure of two fault systems that approximately define the northern and southern coasts of the island suggest an east-west trend in relative plate motion, which is consistent with previous findings. The intervening area consists of en echelon mountain ranges thrust up at the restraining bend from the early Miocene. A Pleistocene volcanic province within this area is interpreted as defining a diffuse extensional fault termination of the southern strike-slip fault zone.

  13. A twin study of differences in the response of plasma ghrelin to a milkshake preload in restrained eaters

    PubMed Central

    Myhre, Rachel; Kratz, Mario; Goldberg, Jack; Polivy, Janet; Melhorn, Susan; Buchwald, Dedra; Cummings, David E.; Schur, Ellen A.

    2014-01-01

    Background Genetic, physiological, and psychological factors can affect food intake, but twin studies can distinguish inherited from environmental contributors. We examined the influence of attempted cognitive control of eating (“restrained eating”) on levels of appetite-regulating hormones. Methods Sixteen female, monozygotic twin pairs, discordant for Restraint Scale score (i.e., one twin a restrained eater with score > 15 whereas the co-twin was unrestrained), were selected from the University of Washington Twin Registry. Serial plasma ghrelin concentrations were monitored during meals and a preload study paradigm involving intake of a milkshake followed by an ad libitum ice cream “taste test.” Results Body weight, body mass index, resting energy expenditure, and fasting leptin levels were very similar between restrained and unrestrained twins. In a preload study, twins ate similar amounts of ice cream shortly after drinking identical milkshakes (mean ±SD; restrained 239 ±158 vs. unrestrained 228 ±132 kilocalories; P = 0.83). However, ghrelin concentrations during the preload study were significantly higher (P = 0.03) in restrained twins than in their unrestrained co-twins. Regardless of restraint status, ghrelin levels prior to the preload study were prospectively and positively associated with ice cream intake (P = 0.001). Conclusions Compared to their unrestrained co-twins, restrained twins had higher endogenous ghrelin levels during a preload study, but ate similar amounts. This finding is consistent with exertion of cognitive control relative to the state of physiologic appetite stimulation. Moreover, these findings in twins suggest that higher ghrelin levels result from restrained eating behavior and not from genetic predisposition. PMID:24534168

  14. Restrained expression, a method to overproduce toxic membrane proteins by exploiting operator-repressor interactions.

    PubMed

    Narayanan, Anoop; Ridilla, Marc; Yernool, Dinesh A

    2011-01-01

    A major rate-limiting step in determining structures of membrane proteins is heterologous protein production. Toxicity often associated with rapid overexpression results in reduced biomass along with low yields of target protein. Mitigation of toxic effects was achieved using a method we call "restrained expression," a controlled reduction in the frequency of transcription initiation by exploiting the infrequent transitions of Lac repressor to a free state from its complex with the lac-operator site within a T7lac promoter that occur in the absence of the inducer isopropyl β-D-1-thiogalactopyranoside. In addition, production of the T7 RNA polymerase that drives transcription of the target is limited using the tightly regulated arabinose promoter in Escherichia coli strain BL21-AI. Using this approach, we can achieve a 200-fold range of green fluorescent protein expression levels. Application to members of a family of ion pumps results in 5- to 25-fold increases in expression over the benchmark BL21(DE3) host strain. A viral ion channel highly toxic to E. coli can also be overexpressed. In comparative analyses, restrained expression outperforms commonly used E. coli expression strategies. The mechanism underlying improved target protein yield arises from minimization of protein aggregation and proteolysis that reduce membrane integrity and cell viability. This study establishes a method to overexpress toxic proteins. PMID:21031485

  15. Cilengitide restrains the osteoclast-like bone resorbing activity of myeloma plasma cells.

    PubMed

    Tucci, Marco; Stucci, Stefania; Felici, Claudia; Cafforio, Paola; Resta, Leonardo; Rossi, Roberta; Silvestris, Franco

    2016-04-01

    Cilengitide (CLG) is an inhibitor of both αv β3 and αv β5 integrins, with a defined anti-tumour effect in glioblastoma. Pre-clinical studies demonstrate its ability to restrain the bone resorbing property of metastatic osteotropic tumours and we have previously shown that the disablement of αv β3 in multiple myeloma (MM) plasma cells results in exhaustion of their in vitro osteoclast (OC)-like activity on bone substrate. Here, we investigated the effect of CLG on this functional property of MM cells. Both αv β3 and αv β5 were measured on primary marrow MM cells from 19 patients, and the effect of CLG on proliferation, apoptosis and adhesion was investigated in parallel with MM cell lines and OCs from healthy donors. In addition, the effect of CLG on the capability of malignant plasma cells to produce erosive lacunae on calcium phosphate was explored in relation to the activation of intracellular kinases of molecular pathways of both integrins. Ultrastructural microscopy was used to evaluate the morphological changes in MM cells due to the effect of CLG on cell adhesion. The data from our study demonstrate that CLG restrains the bone resorbing function of MM cells by disabling their adhesion properties. Further investigations in pre-clinical studies of osteotropic tumours are warranted. PMID:26728969

  16. A nonlinear theory for spinning anisotropic beams using restrained warping functions

    NASA Technical Reports Server (NTRS)

    Ie, C. A.; Kosmatka, J. B.

    1993-01-01

    A geometrically nonlinear theory is developed for spinning anisotropic beams having arbitrary cross sections. An assumed displacement field is developed using the standard 3D kinematics relations to describe the global beam behavior supplemented with an additional field that represents the local deformation within the cross section and warping out of the cross section plane. It is assumed that the magnitude of this additional field is directly proportional to the local stress resultants. In order to take into account the effects of boundary conditions, a restraining function is introduced. This function plays the role of reducing the amount of free warping deformation throughout the field due to the restraint of the cross section(s) at the end(s) of the beam, e.g., in the case of a cantilever beam. Using a developed ordering scheme, the nonlinear strains are calculated to the third order. The FEM is developed using the weak form variational formulation. Preliminary interesting numerical results have been obtained that indicate the role of the restraining function in the case of a cantilever beam with circular cross section. These results are for the cases of a tip displacement (static) and free vibration studies for both isotropic and anisotropic materials with varied fiber orientations.

  17. Thoracic injuries to contained and restrained occupants in single-vehicle pure rollover crashes.

    PubMed

    Bambach, M R; Grzebieta, R H; McIntosh, A S

    2013-01-01

    Around one in three contained and restrained seriously injured occupants in single-vehicle pure rollover crashes receive a serious injury to the thorax. With dynamic rollover test protocols currently under development, there is a need to understand the nature and cause of serious thoracic injuries incurred in rollover events. This will allow decisions to be made with regards to adoption of a suitable crash test dummy and appropriate thoracic injury criteria in such protocols. Valid rollover occupant protection test protocols will lead to vehicle improvements that will reduce the high trauma burden of vehicle rollover crashes. This paper presents an analysis of contained and restrained occupants involved in single-vehicle pure rollover crashes that occurred in the United States between 2000 and 2009 (inclusive). Serious thoracic injury typology and causality are determined. A logistic regression model is developed to determine associations between the incidence of serious thoracic injury and the human, vehicle and environmental characteristics of the crashes. Recommendations are made with regards to the appropriate assessment of potential thoracic injury in dynamic rollover occupant protection crash test protocols. PMID:23200447

  18. Neurofeedback reduces overeating episodes in female restrained eaters: a randomized controlled pilot-study.

    PubMed

    Schmidt, Jennifer; Martin, Alexandra

    2015-12-01

    Overeating episodes, despite of intentions to control weight, are a common problem among women. Recurring episodes of overeating and dietary failure have been reported to result in higher Body Mass Indexes and to induce severe distress even in non-clinical groups. Based on findings from physiological research on eating behavior and craving, as well as previous biofeedback studies, we derived a cue exposure based EEG neurofeedback protocol to target overeating episodes. The treatment was evaluated in a randomized controlled trial, comparing a neurofeedback group (NFG; n = 14) with a waiting list control group (WLG; n = 13) in a sub-clinical sample of female restrained eaters. At post-treatment, the number of weekly overeating episodes and subsequent distress were significantly reduced in the NFG compared to the WLG (p < .01; r > .50). In a 3 month follow-up, effects in the NFG remained stable. As secondary outcomes, perceived dieting success was enhanced after the treatment. At follow-up, additional beneficial effects on trait food craving were observed. Altogether, we found preliminary evidence for the cue exposure neurofeedback against overeating episodes in female restrained eaters, although specific effects and underlying mechanisms still have to be explored in future research. PMID:26164414

  19. Bcl6 Sets a Threshold for Antiviral Signaling by Restraining IRF7 Transcriptional Program

    PubMed Central

    Xu, Feng; Kang, Yanhua; Zhuang, Ningtong; Lu, Zhe; Zhang, Hang; Xu, Dakang; Ding, Yina; Yin, Hongping; Shi, Liyun

    2016-01-01

    The coordination of restraining and priming of antiviral signaling constitute a fundamental aspect of immunological functions. However, we currently know little about the molecular events that can translate the pathogenic cues into the appropriate code for antiviral defense. Our present study reports a specific role of B cell lymphoma (Bcl)6 as a checkpoint in the initiation of the host response to cytosolic RNA viruses. Remarkably, Bcl6 specifically binds to the interferon-regulatory factor (IRF)7 loci and restrains its transcription, thereby functioning as a negative regulator for interferon (IFN)-β production and antiviral responses. The signal-controlled turnover of the Bcl6, most likely mediated by microRNA-127, coordinates the antiviral response and inflammatory sequelae. Accordingly, de-repression of Bcl6 resulted in a phenotypic conversion of macrophages into highly potent IFN-producing cells and rendered mice more resistant to pathogenic RNA virus infection. The failure to remove the Bcl6 regulator, however, impedes the antiviral signaling and exaggerates viral pneumonia in mice. We thus reveal a novel key molecular checkpoint to orchestrate antiviral innate immunity. PMID:26728228

  20. The relation of hedonic hunger and restrained eating to lateralized frontal activation.

    PubMed

    Winter, S R; Feig, E H; Kounios, J; Erickson, B; Berkowitz, S; Lowe, M R

    2016-09-01

    Asymmetrical alpha activation in the prefrontal cortex (frontal asymmetry) in electroencephalography (EEG) has been related to eating behavior. Prior studies linked dietary restraint with right frontal asymmetry [1] and disinhibition with left frontal asymmetry [2]. The current study simultaneously assessed restrained eating and hedonic hunger (drive for food reward in the absence of hunger) in relation to frontal asymmetry. Resting-state EEG and measures of restrained eating (Revised Restraint Scale; RRS) and hedonic hunger (Power of Food Scale; PFS) were assessed in 61 non-obese adults. Individually, hedonic hunger predicted left asymmetry. However, PFS and RRS were correlated (r=0.48, p<0.05) and there was a significant interaction between PFS and RRS on frontal asymmetry, p<0.01. Results indicated that those high in hedonic hunger exhibited left asymmetry irrespective of RRS scores; among those low in PFS, only those high in RRS showed right asymmetry. Results were consistent with literature linking avoidant behaviors (restraint) with right-frontal asymmetry and approach behaviors (binge eating) with left-frontal asymmetry. It appears that a strong drive toward palatable foods predominates at a neural level even when restraint is high. Findings suggest that lateralized frontal activity is an indicator of motivation both to consume and to avoid consuming highly palatable foods. PMID:27133731

  1. Ductility demands on buckling-restrained braced frames under earthquake loading

    NASA Astrophysics Data System (ADS)

    Fahnestock, Larry A.; Sause, Richard; Ricles, James M.; Lu, Le-Wu

    2003-12-01

    Accurate estimates of ductility demands on buckling-restrained braced frames (BRBFs) are crucial to performance-based design of BRBFs. An analytical study on the seismic behavior of BRBFs has been conducted at the ATLSS Center, Lehigh University to prepare for an upcoming experimental program. The analysis program DRAIN-2DX was used to model a one-bay, four-story prototype BRBF including material and geometric nonlinearities. The buckling-restrained brace (BRB) model incorporates both isotropic and kinematic hardening. Nonlinear static pushover and time-history analyses were performed on the prototype BRBF. Performance objectives for the BRBs were defined and used to evaluate the time-history analysis results. Particular emphasis was placed on global ductility demands and ductility demands on the BRBs. These demands were compared with anticipated ductility capacities. The analysis results, along with results from similar previous studies, are used to evaluate the BRBF design provisions that have been recommended for codification in the United States. The results show that BRB maximum ductility demands can be as high as 20 to 25. These demands significantly exceed those anticipated by the BRBF recommended provisions. Results from the static pushover and time-history analyses are used to demonstrate why the ductility demands exceed those anticipated by the recommended provisions. The BRB qualification testing protocol contained in the BRBF recommended provisions is shown to be inadequate because it requires only a maximum ductility demand of at most 7.5. Modifications to the testing protocol are recommended.

  2. Mathematical modeling and full-scale shaking table tests for multi-curve buckling restrained braces

    NASA Astrophysics Data System (ADS)

    Tsai, C. S.; Lin, Yungchang; Chen, Wenshin; Su, H. C.

    2009-09-01

    Buckling restrained braces (BRBs) have been widely applied in seismic mitigation since they were introduced in the 1970s. However, traditional BRBs have several disadvantages caused by using a steel tube to envelope the mortar to prevent the core plate from buckling, such as: complex interfaces between the materials used, uncertain precision, and time consumption during the manufacturing processes. In this study, a new device called the multi-curve buckling restrained brace (MC-BRB) is proposed to overcome these disadvantages. The new device consists of a core plate with multiple neck portions assembled to form multiple energy dissipation segments, and the enlarged segment, lateral support elements and constraining elements to prevent the BRB from buckling. The enlarged segment located in the middle of the core plate can be welded to the lateral support and constraining elements to increase buckling resistance and to prevent them from sliding during earthquakes. Component tests and a series of shaking table tests on a full-scale steel structure equipped with MC-BRBs were carried out to investigate the behavior and capability of this new BRB design for seismic mitigation. The experimental results illustrate that the MC-BRB possesses a stable mechanical behavior under cyclic loadings and provides good protection to structures during earthquakes. Also, a mathematical model has been developed to simulate the mechanical characteristics of BRBs.

  3. Buckling Behavior of Long Anisotropic Plates Subjected to Elastically Restrained Thermal Expansion

    NASA Technical Reports Server (NTRS)

    Nemeth, Michael P.

    2002-01-01

    An approach for synthesizing buckling results for, and behavior of, thin balanced and unbalanced symmetric laminates that are subjected to uniform heating or cooling and elastically restrained against thermal expansion or contraction is presented. This approach uses a nondimensional analysis for infinitely long, flexurally anisotropic plates that are subjected to combined mechanical loads and is based on useful nondimensional parameters. In addition, stiffness-weighted laminate thermal-expansion parameters and compliance coefficients are derived that are used to determine critical temperatures in terms of physically intuitive mechanical-buckling coefficients. The effects of membrane orthotropy and membrane anisotropy are included in the general formulation. Many results are presented for some common laminates that are intended to facilitate a structural designer's transition to the use of generic buckling design curves. Several curves that illustrate the fundamental parameters used in the analysis are presented, for nine contemporary material systems, that provide physical insight into the buckling response in addition to providing useful design data. Examples are presented that demonstrate the use of generic design curves. The analysis approach and generic results indicate the effects and characteristics of elastically restrained laminate thermal expansion or contraction, membrane orthotropy and anisotropy, and flexural orthotropy and anisotropy in a very general and unifying manner.

  4. Collision-avoidance behaviors of minimally restrained flying locusts to looming stimuli

    PubMed Central

    Chan, R. WM.; Gabbiani, F.

    2013-01-01

    SUMMARY Visually guided collision avoidance is of paramount importance in flight, for instance to allow escape from potential predators. Yet, little is known about the types of collision-avoidance behaviors that may be generated by flying animals in response to an impending visual threat. We studied the behavior of minimally restrained locusts flying in a wind tunnel as they were subjected to looming stimuli presented to the side of the animal, simulating the approach of an object on a collision course. Using high-speed movie recordings, we observed a wide variety of collision-avoidance behaviors including climbs and dives away from – but also towards – the stimulus. In a more restrained setting, we were able to relate kinematic parameters of the flapping wings with yaw changes in the trajectory of the animal. Asymmetric wing flapping was most strongly correlated with changes in yaw, but we also observed a substantial effect of wing deformations. Additionally, the effect of wing deformations on yaw was relatively independent of that of wing asymmetries. Thus, flying locusts exhibit a rich range of collision-avoidance behaviors that depend on several distinct aerodynamic characteristics of wing flapping flight. PMID:23364572

  5. The effects of emotion regulation on the desire to overeat in restrained eaters.

    PubMed

    Svaldi, Jennifer; Tuschen-Caffier, Brunna; Lackner, Helmut K; Zimmermann, Sabine; Naumann, Eva

    2012-10-01

    The aim of the present study was to test whether emotion regulation (ER) strategies are underlying processes in the link between negative emotions and the desire to overeat (DTE) in high restrained eaters (HR). Forty-eight female HR and 46 female low restrained eaters (LR) watched three sadness inducing film clips. Thereby, participants were randomly assigned to and trained in one of three conditions while watching the first two clips: to suppress upcoming emotions, to accept upcoming emotions or to reappraise the situation. After that, they participated in an experiment in which the learned ER strategy was implemented while watching the third sadness inducing film clip. DTE and sadness were assessed prior to and at the end of each clip. Additionally, physiological measures of the sympathetic and parasympathetic branch were obtained. In the HR group emotion acceptance and suppression lead to a significant increase of the DTE from baseline to post-film, while there was no change in DTE in the reappraisal condition. However, psychophysiological measures were not moderated by ER strategies. The results are discussed in terms of the limited resource model. PMID:22580220

  6. Make up your mind about food: A healthy mindset attenuates attention for high-calorie food in restrained eaters.

    PubMed

    Werthmann, Jessica; Jansen, Anita; Roefs, Anne

    2016-10-01

    Attention bias for food could be a cognitive pathway to overeating in obesity and restrained eating. Yet, empirical evidence for individual differences (e.g., in restrained eating and body mass index) in attention bias for food is mixed. We tested experimentally if temporarily induced health versus palatability mindsets influenced attention bias for food, and whether restrained eating moderated this relation. After manipulating mindset (health vs. palatability) experimentally, food-related attention bias was measured by eye-movements (EM) and response latencies (RL) during a visual probe task depicting high-calorie food and non-food. Restrained eating was assessed afterwards. A significant interaction of mindset and restrained eating on RL bias emerged, β = 0.36, t(58) = 2.05, p = 0.045: A health mindset - as compared to a palatability mindset - attenuated attention bias for high-caloric food only in participants with higher eating restraint. No effects were observed on EM biases. The current results demonstrate that state differences in health versus palatability mindsets can cause attenuated attention bias for high-calorie food cues in participants with higher eating restraint. Our findings add to emerging evidence that state differences in mindsets can bias attention for food, above the influence of trait differences. PMID:27174250

  7. General principles of antimicrobial therapy.

    PubMed

    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. PMID:21282489

  8. Antimicrobial Peptides from Fish

    PubMed Central

    Masso-Silva, Jorge A.; Diamond, Gill

    2014-01-01

    Antimicrobial peptides (AMPs) are found widely distributed through Nature, and participate in the innate host defense of each species. Fish are a great source of these peptides, as they express all of the major classes of AMPs, including defensins, cathelicidins, hepcidins, histone-derived peptides, and a fish-specific class of the cecropin family, called piscidins. As with other species, the fish peptides exhibit broad-spectrum antimicrobial activity, killing both fish and human pathogens. They are also immunomodulatory, and their genes are highly responsive to microbes and innate immuno-stimulatory molecules. Recent research has demonstrated that some of the unique properties of fish peptides, including their ability to act even in very high salt concentrations, make them good potential targets for development as therapeutic antimicrobials. Further, the stimulation of their gene expression by exogenous factors could be useful in preventing pathogenic microbes in aquaculture. PMID:24594555

  9. Antimicrobials in periodontal maintenance.

    PubMed

    Jorgensen, M G; Slots, J

    2001-01-01

    Mechanical and chemical antimicrobial intervention is the mainstay of preventive periodontal therapy. Successful periodontal maintenance care depends upon the ability of oral health care professionals to combat periodontal infections, and patient compliance with prescribed follow-up care. Since tooth brushing, flossing, and oral rinsing do not reach pathogens present in furcations and at the depths of deep periodontal pockets, adequate oral hygiene should include subgingival treatment with home irrigators or other appropriate self-care remedies in patients with these conditions. Povidone-iodine for professional use and diluted bleach for self-care are inexpensive and valuable antimicrobial agents in periodontal maintenance. The present article outlines the prudent use of antimicrobial therapy in periodontal maintenance. PMID:11603305

  10. PROGRAMS FOR MONITORING ANTIMICROBIAL RESISTANCE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Use of antimicrobials has increased in both human and veterinary medicine and the emergence of resistance to antimicrobials has become a global problem. This is due, in part, to the widespread availability of antimicrobials and the efficacy they impart in control of certain infectious diseases. An...

  11. Antimicrobial Graft Copolymer Gels.

    PubMed

    Harvey, Amanda C; Madsen, Jeppe; Douglas, C W Ian; MacNeil, Sheila; Armes, Steven P

    2016-08-01

    In view of the growing worldwide rise in microbial resistance, there is considerable interest in designing new antimicrobial copolymers. The aim of the current study was to investigate the relationship between antimicrobial activity and copolymer composition/architecture to gain a better understanding of their mechanism of action. Specifically, the antibacterial activity of several copolymers based on 2-(methacryloyloxy)ethyl phosphorylcholine [MPC] and 2-hydroxypropyl methacrylate (HPMA) toward Staphylococcus aureus was examined. Both block and graft copolymers were synthesized using either atom transfer radical polymerization or reversible addition-fragmentation chain transfer polymerization and characterized via (1)H NMR, gel permeation chromatography, rheology, and surface tensiometry. Antimicrobial activity was assessed using a range of well-known assays, including direct contact, live/dead staining, and the release of lactate dehydrogenase (LDH), while transmission electron microscopy was used to study the morphology of the bacteria before and after the addition of various copolymers. As expected, PMPC homopolymer was biocompatible but possessed no discernible antimicrobial activity. PMPC-based graft copolymers comprising PHPMA side chains (i.e. PMPC-g-PHPMA) significantly reduced both bacterial growth and viability. In contrast, a PMPC-PHPMA diblock copolymer comprising a PMPC stabilizer block and a hydrophobic core-forming PHPMA block did not exhibit any antimicrobial activity, although it did form a biocompatible worm gel. Surface tensiometry studies and LDH release assays suggest that the PMPC-g-PHPMA graft copolymer exhibits surfactant-like activity. Thus, the observed antimicrobial activity is likely to be the result of the weakly hydrophobic PHPMA chains penetrating (and hence rupturing) the bacterial membrane. PMID:27409712

  12. Getting a bigger slice of the pie. Effects on eating and emotion in restrained and unrestrained eaters.

    PubMed

    Polivy, Janet; Herman, C Peter; Deo, Rajbir

    2010-12-01

    Manipulated perceptions of the portion size of food influence subsequent eating by restrained and unrestrained eaters. In the present study, all participants were served a same-sized slice of pizza. For one-third of participants, their slice appeared larger than the slice being served to another ostensible participant, another third perceived their slice as smaller, and the final third did not see a second slice. All participants then proceeded to "taste and rate" cookies in an ad lib eating opportunity. A significant interaction reflected the fact that when the pizza slice was perceived as large, restrained eaters tended to eat more cookies whereas unrestrained eaters tended to eat less cookies. Emotion data suggest that the differential responses of restrained and unrestrained eaters to the belief that they have overeaten relative to another eater influenced their subsequent dissimilar ad lib eating behavior. PMID:20691231

  13. A regulatory focus perspective on eating behavior: how prevention and promotion focus relates to emotional, external, and restrained eating

    PubMed Central

    Pfattheicher, Stefan; Sassenrath, Claudia

    2014-01-01

    By applying regulatory focus theory (RFT) to the context of eating behavior, the present research examines the relations between individual differences in the two motivational orientations as conceptualized in RFT, that is, prevention-focused and promotion-focused self-regulation and emotional, external, and restrained eating. Building on a representative study conducted in the Netherlands (N = 4,230), it is documented that individual differences in prevention focus are positively related to emotional eating whereas negligible associations are found in regards to external and restrained eating. Individual differences in promotion focus are positively related to external eating whereas negligible associations are found in regards to emotional and restrained eating. In relating RFT to different eating styles we were able to document significant relations of basic self-regulatory orientations with regard to essential daily behavior associated with health and well-being. The implications for changing eating styles are discussed. PMID:25477840

  14. The effect of brand and caloric information on flavor perception and food consumption in restrained and unrestrained eaters.

    PubMed

    Cavanagh, Kevin V; Kruja, Blina; Forestell, Catherine A

    2014-11-01

    The goal of the current study was to determine whether provision of brand and caloric information affects sensory perception and consumption of a food in restrained (n=84) and unrestrained eaters (n=104). Using a between-subjects 2 × 2 × 3 design, female restrained and unrestrained eaters were asked to taste and rate a cookie that was labeled with a brand associated with healthful eating (Kashi(®)) or one associated with unhealthful eating (Nabisco(®)). Additionally, some participants were presented with a nutrition label alongside the brand name indicating that one serving contained 130 calories (Low-Calorie Condition), or 260 calories (High-Calorie Condition). The remaining participants were not shown a nutrition label (No Label Condition). Results indicated that those in the No Label or the High-Calorie Condition perceived the healthful branded cookie to have a better flavor than those who received the unhealthful branded cookie regardless of their restraint status. However, restrained eaters in the No Label Condition consumed more of the healthful than the unhealthful branded cookie, whereas those in the Low-Calorie Condition consumed more of the unhealthful than the healthful branded cookie. In contrast, unrestrained eaters ate more of the healthful branded cookie regardless of the caloric information provided. Thus, although restrained and unrestrained eaters' perceptions are similarly affected by branding and caloric information, brands and caloric information interact to affect restrained eaters' consumption. This study reveals that labeling foods as low calorie may create a halo effect which may lead to over-consumption of these foods in restrained eaters. PMID:24979333

  15. Gun Violence Restraining Orders: Alternative or Adjunct to Mental Health-Based Restrictions on Firearms?

    PubMed

    Frattaroli, Shannon; McGinty, Emma E; Barnhorst, Amy; Greenberg, Sheldon

    2015-06-01

    The gun violence restraining order (GVRO) is a new tool for preventing gun violence. Unlike traditional approaches to prohibiting gun purchase and possession, which rely on a high threshold (adjudication by criminal justice or mental health systems) before intervening, the GVRO allows family members and intimate partners who observe a relative's dangerous behavior and believe it may be a precursor to violence to request a GVRO through the civil justice system. Once issued by the court, a GVRO authorizes law enforcement to remove any guns in the respondent's possession and prohibits the respondent from purchasing new guns. In September 2014, California's governor signed AB1014 into law, making California the first U.S. state to enact a GVRO law. This article describes the GVRO and the rationale behind the concept, considers case examples to assess the potential impact of the GVRO as a strategy for preventing gun violence, and reviews the content of the California law. PMID:25990840

  16. Restraining order for dendritic cells: all quiet on the fetal front.

    PubMed

    Chakraborty, Rana; Pulendran, Bali

    2009-07-01

    The paradoxical ability to launch effective immunity against pathogens while avoiding the horror autotoxicus of autoimmunity is one of the most remarkable features of the mammalian immune system. This assumes a particular evolutionary significance at the maternal/fetal interface, where avoidance of immune reactivity to the fetus is vital to the propagation of the species itself. Several mechanisms of suppressing maternal immunity against the fetus have been described. The article by Collins et al. in this issue of the JCI describes a novel mechanism of avoiding immune surveillance in which the migratory capacity of dendritic cells at the maternal/fetal interface is restrained (see the related article beginning on page 2062). PMID:19603541

  17. Conditioned lick behavior and evoked responses using whisker twitches in head restrained rats.

    PubMed

    Topchiy, Irina A; Wood, Rachael M; Peterson, Breeanne; Navas, Jinna A; Rojas, Manuel J; Rector, David M

    2009-01-30

    To examine whisker barrel evoked response potentials in chronically implanted rats during behavioral learning with very fast response times, rats must be calm while immobilized with their head restrained. We quantified their behaviors during training with an ethogram and measured each individual animals' progress over the training period. Once calm under restraint, rats were conditioned to differentiate between a reward and control whisker twitch, then provide a lick response when presented with the correct stimulus, rewarded by a drop of water. Rats produced the correct licking response (after reward whisker twitch), and learned not to lick after a control whisker was twitched. By implementing a high-density 64-channel electrocorticogram (ECoG) electrode array, we mapped the barrel field of the somatosensory cortex with high spatial and temporal resolution during conditioned lick behaviors. In agreement with previous reports, we observe a larger evoked response after training, probably related to mechanisms of cortical plasticity. PMID:18718491

  18. Non-restrained measurement of Young's modulus for soft tissue using a photoacoustic technique

    NASA Astrophysics Data System (ADS)

    Wadamori, Naoki

    2014-09-01

    A miniaturized sensor was developed to determine the Young's modulus of tumors based on photoacoustic spectroscopy. The sensor had a chamber height of 5.3 mm and diameter of 5.8 mm; thus, this device is smaller than conventional endoscopes, the outer diameters of which are typically about 10 mm. A non-restrained methodology for determining the Young's modulus of tumors was proposed based on the resonance frequency of the photoacoustic signal. The proposed approach was applied to silicone rubbers with six different Young's moduli (30, 64, 123, 224, 396, and 574 kPa) and showed good resolution (±2 kPa) and high reproducibility. These results show that the photoacoustic technique can be applied to mechanically characterize soft tissue by diagnostic endoscopy.

  19. Rupture termination at restraining bends: The last great earthquake on the Altyn Tagh Fault

    NASA Astrophysics Data System (ADS)

    Elliott, Austin J.; Oskin, Michael E.; Liu-Zeng, Jing; Shao, Yanxiu

    2015-04-01

    Strike-slip rupture propagation falters where changes in fault strike increase Coulomb failure stress. Numerical models of this phenomenon offer predictions of rupture extent based on bend geometry, but have not been verified with field data. To test model predictions of rupture barriers, we examine rupture extent along a section of the sinistral Altyn Tagh Fault punctuated by three major double bends. We measure 3-8 m offsets and map >95 km of continuous scarps that define the most recent surface rupture. We document the eastern terminus of this rupture within the Aksay bend, where an undeformed Pleistocene alluvial fan we mapped and dated overlaps the fault. We conclude, based on this geomorphologic evidence, that multiple Holocene ruptures have stopped in the Aksay bend. Our field data validate model predictions of rupture termination at a >18° restraining bend and support use of geometric parameters to define expected earthquake sizes in seismic hazard models.

  20. Total Synthesis and Selective Activity of a NewClass of Conformationally Restrained Epothilones

    PubMed Central

    Alhamadsheh, Mamoun M.; Gupta, Shuchi; Hudson, Richard A.; Perera, Lalith

    2009-01-01

    Stereoselective total syntheses of two novel conformationally restrained epothilone analogues are described. Evans asymmetric alkylation, Brown allylation, and a diastereoselective aldol reaction served as the key steps in the stereoselective synthesis of one of the two key fragments of the convergent synthetic approach.Enzyme resolution was employed to obtain the second fragment as a single enantiomer. The molecules were assembled by esterification, followed by ring-closing metathesis. In preliminary cytotoxicity studies, one of the analogues showed strong and selective growth inhibitory activity against two leukemia cell lines over solid human tumor cell lines. The precise biological mechanism of action and high degree of selectivity of this analogue remain to be examined. PMID:17955508

  1. Buckling Behavior of Long Anisotropic Plates Subjected to Elastically Restrained Thermal Expansion and Contraction

    NASA Technical Reports Server (NTRS)

    Nemeth, Michael P.

    2004-01-01

    An approach for synthesizing buckling results for thin balanced and unbalanced symmetric laminates that are subjected to uniform heating or cooling and elastically restrained against thermal expansion or contraction is presented. This approach uses a nondimensional analysis for infinitely long, flexural anisotropic plates that are subjected to combined mechanical loads. In addition, stiffness-weighted laminate thermal-expansion parameters and compliance coefficients are derived that are used to determine critical temperatures in terms of physically intuitive mechanical-buckling coefficients. Many results are presented for some common laminates that are intended to facilitate a structural designer s transition to the use of the generic buckling design curves. Several curves that illustrate the fundamental parameters used in the analysis are presented, for nine contemporary material systems, that provide physical insight into the buckling response in addition to providing useful design data. Examples are presented that demonstrate the use of the generic design curves.

  2. Antimicrobial Tolerance in Biofilms.

    PubMed

    Stewart, Philip S

    2015-06-01

    The tolerance of microorganisms in biofilms to antimicrobial agents is examined through a meta-analysis of literature data. A numerical tolerance factor comparing the rates of killing in the planktonic and biofilm states is defined to provide a quantitative basis for the analysis. Tolerance factors for biocides and antibiotics range over three orders of magnitude. This variation is not explained by taking into account the molecular weight of the agent, the chemistry of the agent, the substratum material, or the speciation of the microorganisms. Tolerance factors do depend on the areal cell density of the biofilm at the time of treatment and on the age of the biofilm as grown in a particular experimental system. This suggests that there is something that happens during biofilm maturation, either physical or physiological, that is essential for full biofilm tolerance. Experimental measurements of antimicrobial penetration times in biofilms range over orders of magnitude, with slower penetration (>12 min) observed for reactive oxidants and cationic molecules. These agents are retarded through the interaction of reaction, sorption, and diffusion. The specific physiological status of microbial cells in a biofilm contributes to antimicrobial tolerance. A conceptual framework for categorizing physiological cell states is discussed in the context of antimicrobial susceptibility. It is likely that biofilms harbor cells in multiple states simultaneously (e.g., growing, stress-adapted, dormant, inactive) and that this physiological heterogeneity is an important factor in the tolerance of the biofilm state. PMID:26185072

  3. [Antimicrobial prophylaxis in surgery].

    PubMed

    Stastník, Miloslav

    2004-04-01

    Antimicrobial prophylaxis is an important factor influencing the risk of infection at the spot of surgical interventions (SSI). SSIs are the most important nosocomial infections of hospitalized surgical patients; they are responsible for increases of 10 to 20 % in the total costs of treatment. The efficacy of antimicrobial prophylaxis hinges on four basic factors. The first is a correctly indicated prophylaxis (in surgical operations with a confirmed reduction of SSI risk after prophylaxis and/or in cases of surgical operations, where a possible early or organ SSI could have tragic consequences). The second factor is the choice of the best possible antimicrobial for a specific indication. The third factor is the best possible time for the administration of prophylaxis (in most indications at the beginning of anaesthesia). The fourth factor influencing the efficacy of prophylaxis is its administration for only the absolutely minimum time period necessary (in most indications best is a single administration, possibly including a second peroperative ATB dose). The high rate of errors in the actual practice of prophylaxis and the confirmed efficacy of implementing local recommendations indicate that it is absolutely necessary to define national and local recommendations for antimicrobial prophylaxis, to ensure that surgeons adhere to these recommendations and to initiate SSI surveillance in the Czech Republic. PMID:15146385

  4. Endolysins as antimicrobials.

    PubMed

    Nelson, Daniel C; Schmelcher, Mathias; Rodriguez-Rubio, Lorena; Klumpp, Jochen; Pritchard, David G; Dong, Shengli; Donovan, David M

    2012-01-01

    Peptidoglycan (PG) is the major structural component of the bacterial cell wall. Bacteria have autolytic PG hydrolases that allow the cell to grow and divide. A well-studied group of PG hydrolase enzymes are the bacteriophage endolysins. Endolysins are PG-degrading proteins that allow the phage to escape from the bacterial cell during the phage lytic cycle. The endolysins, when purified and exposed to PG externally, can cause "lysis from without." Numerous publications have described how this phenomenon can be used therapeutically as an effective antimicrobial against certain pathogens. Endolysins have a characteristic modular structure, often with multiple lytic and/or cell wall-binding domains (CBDs). They degrade the PG with glycosidase, amidase, endopeptidase, or lytic transglycosylase activities and have been shown to be synergistic with fellow PG hydrolases or a range of other antimicrobials. Due to the coevolution of phage and host, it is thought they are much less likely to invoke resistance. Endolysin engineering has opened a range of new applications for these proteins from food safety to environmental decontamination to more effective antimicrobials that are believed refractory to resistance development. To put phage endolysin work in a broader context, this chapter includes relevant studies of other well-characterized PG hydrolase antimicrobials. PMID:22748813

  5. Antimicrobial Tolerance in Biofilms

    PubMed Central

    Stewart, Philip S.

    2015-01-01

    The tolerance of microorganisms in biofilms to antimicrobial agents is examined through a meta-analysis of literature data. A numerical tolerance factor comparing the rates of killing in the planktonic and biofilm states is defined to provide a quantitative basis for the analysis. Tolerance factors for biocides and antibiotics range over three orders of magnitude. This variation is not explained by taking into account the molecular weight of the agent, the chemistry of the agent, the substratum material, or the speciation of the microorganisms. Tolerance factors do depend on the areal cell density of the biofilm at the time of treatment and on the age of the biofilm as grown in a particular experimental system. This suggests that there is something that happens during biofilm maturation, either physical or physiological, that is essential for full biofilm tolerance. Experimental measurements of antimicrobial penetration times in biofilms range over orders of magnitude, with slower penetration (>12 min) observed for reactive oxidants and cationic molecules. These agents are retarded through the interaction of reaction, sorption, and diffusion. The specific physiological status of microbial cells in a biofilm contributes to antimicrobial tolerance. A conceptual framework for categorizing physiological cell states is discussed in the context of antimicrobial susceptibility. It is likely that biofilms harbor cells in multiple states simultaneously (e.g., growing, stress-adapted, dormant, inactive) and that this physiological heterogeneity is an important factor in the tolerance of the biofilm state. PMID:26185072

  6. Multidimensional signatures in antimicrobial peptides

    PubMed Central

    Yount, Nannette Y.; Yeaman, Michael R.

    2004-01-01

    Conventional analyses distinguish between antimicrobial peptides by differences in amino acid sequence. Yet structural paradigms common to broader classes of these molecules have not been established. The current analyses examined the potential conservation of structural themes in antimicrobial peptides from evolutionarily diverse organisms. Using proteomics, an antimicrobial peptide signature was discovered to integrate stereospecific sequence patterns and a hallmark three-dimensional motif. This striking multidimensional signature is conserved among disulfide-containing antimicrobial peptides spanning biological kingdoms, and it transcends motifs previously limited to defined peptide subclasses. Experimental data validating this model enabled the identification of previously unrecognized antimicrobial activity in peptides of known identity. The multidimensional signature model provides a unifying structural theme in broad classes of antimicrobial peptides, will facilitate discovery of antimicrobial peptides as yet unknown, and offers insights into the evolution of molecular determinants in these and related host defense effector molecules. PMID:15118082

  7. Head Excursion of Restrained Human Volunteers and Hybrid III Dummies in Steady State Rollover Tests

    PubMed Central

    Moffatt, Edward; Hare, Barry; Hughes, Raymond; Lewis, Lance; Iiyama, Hiroshi; Curzon, Anne; Cooper, Eddie

    2003-01-01

    Seatbelts provide substantial benefits in rollover crashes, yet occupants still receive head and neck injuries from contacting the vehicle roof interior when the roof exterior strikes the ground. Prior research has evaluated rollover restraint performance utilizing anthropomorphic test devices (dummies), but little dynamic testing has been done with human volunteers to learn how they move during rollovers. In this study, the vertical excursion of the head of restrained dummies and human subjects was measured in a vehicle being rotated about its longitudinal roll axis at roll rates from 180-to-360 deg/sec and under static inversion conditions. The vehicle’s restraint design was the commonly used 3-point seatbelt with continuous loop webbing and a sliding latch plate. This paper presents an analysis of the observed occupant motion and provides a comparison of dummy and human motion under similar test conditions. Thirty-five tests (eighteen static and seventeen dynamic) were completed using two different sizes of dummies and human subjects in both near and far-side roll directions. The research indicates that far-side rollovers cause the restrained test subjects to have greater head excursion than near-side rollovers, and that static inversion testing underestimates head excursion for far-side occupants. Human vertical head excursion of up to 200 mm was found at a roll rate of 220 deg/sec. Humans exhibit greater variability in head excursion in comparison to dummies. Transfer of seatbelt webbing through the latch plate did not correlate directly with differences in head excursion. PMID:12941241

  8. PTEN inhibits PREX2-catalyzed activation of RAC1 to restrain tumor cell invasion

    PubMed Central

    Mense, Sarah M.; Barrows, Douglas; Hodakoski, Cindy; Steinbach, Nicole; Schoenfeld, David; Su, William; Hopkins, Benjamin D.; Su, Tao; Fine, Barry; Hibshoosh, Hanina; Parsons, Ramon

    2016-01-01

    The tumor suppressor PTEN restrains cell migration and invasion by a mechanism that is independent of inhibition of the PI3K pathway and decreased activation of the kinase AKT. PREX2, a widely distributed GEF that activates the GTPase RAC1, binds to and inhibits PTEN. We used mouse embryonic fibroblasts and breast cancer cell lines to show that PTEN suppresses cell migration and invasion by blocking PREX2 activity. In addition to metabolizing the phosphoinositide PIP3, PTEN inhibited PREX2-induced invasion by a mechanism that required the tail domain of PTEN, but not its lipid phosphatase activity. Fluorescent nucleotide exchange assays revealed that PTEN inhibited the GEF activity of PREX2 toward RAC1. PREX2 is a frequently mutated GEF in cancer, and examination of human tumor data showed that PREX2 mutation was associated with high PTEN expression. Therefore, we tested whether cancer-derived somatic PREX2 mutants, which accelerate tumor formation of immortalized melanocytes, were inhibited by PTEN. The three stably expressed, somatic PREX2 cancer mutants that we tested were resistant to PTEN-mediated inhibition of invasion but retained the ability to inhibit the lipid phosphatase activity of PTEN. In vitro analysis showed that PTEN did not block the GEF activity of two PREX2 cancer mutants and had a reduced binding affinity for the third. Thus, PTEN antagonized migration and invasion by restraining PREX2 GEF activity, and PREX2 mutants are likely selected in cancer to escape PTEN-mediated inhibition of invasion. PMID:25829446

  9. Restrained Ion Population Transfer: A Novel Ion Transfer Method for Mass Spectrometry.

    SciTech Connect

    Kaiser, Nathan K.; Skulason, Gunnar; Weisbrod, Chad R.; Wu, Si; Zhang, Kai; Prior, David C.; Buschbach, Michael A.; Anderson, Gordon A.; Bruce, James E.

    2008-06-30

    With modern Fourier transform ion cyclotron resonance (ICR) mass spectrometers, ions are created and accumulated exterior to the mass analyzer. The ion accumulation event takes place in a region of higher pressure which allows ions to be thermally cooled before being given kinetic energy and accelerated toward the ICR cell where they are to be decelerated and re-trapped. When gated trapping is used to collect ions in the ICR cell for analysis, mass discrimination can occur due to time-of-flight effects. Also, trapping ions with large axial kinetic energy can decrease the performance of the ICR instrument when compared to the analysis of thermally-cooled ions located at the trap center. Therefore, it is desirable to limit the energy imparted in the ions within the ICR cell as well as minimize time-of-flight effects. The approach presented here for ion transfer called restrained ion population transfer or RIPT provides complete axial control of an ion population throughout the entire transfer sequence from the accumulation region to the ICR cell. This is accomplished by utilization of a number of quadrupole segments arranged in series with independent control of the dc bias voltage applied to each segment of the quadrupole ion guide. This approach circumvents problems associated with time-of-flight effects and minimizes the energy imparted to the ions allowing transfer of the cooled ion packet from the ion accumulation region to the ICR cell. Initial data are presented to illustrate feasibility of restrained ion population transfer. RIPT was also modeled with SIMION 7.0 and simulation results that support our feasibility studies of the ions transfer process are presented.

  10. Differences in Thoracic Injury Causation Patterns Between Seat Belt Restrained Children and Adults

    PubMed Central

    Arbogast, Kristy B.; Locey, Caitlin M.; Zonfrillo, Mark R.

    2012-01-01

    The objective of this research was to delineate age-based differences in specific thoracic injury diagnoses for seat belt restrained rear seat occupants and describe the associated injury causation in order to provide insight into how the load of the seat belt is transferred to occupants of various sizes. Using data from the Crash Investigation Research and Engineering Network (CIREN), 20 cases of rear seated, lap and shoulder belt restrained occupants with AIS2+ thoracic injuries in frontal crashes were reviewed. Seven were children and adolescents age 8–15 years, 5 were 16–24 years, 3 were 25–54 years, and 5 were 55+ years. Six of the seven 8–15 year olds sustained injuries to the lung in the form of pulmonary contusion or pneumothorax. Only three of the seven sustained a skeletal (sternum or rib) fracture; only one of these three involved multiple ribs bilaterally. In contrast, four of the five 16–24 year olds sustained at least one rib fracture - often multiple and bilateral. The adult cohort (25+ years) was involved in predominantly more minor crashes; however they all sustained complex rib fractures – seven of the eight involved multiple ribs, four of the eight were also bilateral. Belt compression – either from the shoulder belt or the lap belt – was identified as the primary cause of the thoracic injuries. Often, there was clear evidence of the location of belt loading from AIS 1 chest contusions or abrasions. These findings have implications for age-based thoracic injury criteria suggesting that that different metrics may be needed for different age groups. PMID:23169131

  11. Effect of Restraining Devices on Facial Fractures in Motor Vehicle Collisions.

    PubMed

    Hwang, Kun; Kim, Joo Ho

    2015-09-01

    The aim of this systematic review is to summarize and critically evaluate the evidence for or against the effectiveness of restraining devices on facial fractures in motor vehicle collisions (MVCs).In a PubMed search, the search terms "facial bone fracture and seat belt," "facial bone fracture and air bag," and "facial bone fracture and restraining" were used. The authors abstracted the odds ratio (OR) and 95% confidence intervals (CIs) from each study. Weighted mean differences and 95% CIs were also calculated. The statistical analysis was performed with Review Manager (The Nordic Cochrane Centre).The authors found 30 potentially relevant articles, of which 6 articles met our inclusion criteria. Five studies were subgrouped, and a meta-analysis of these data suggested beneficial effects of seat belts on decreasing facial fractures in MVCs (n = 15,768,960, OR, 0.46, 95% CI = 0.35-0.60). Three studies were subgrouped, and a meta-analysis of these data suggested that there were beneficial effects of seat belts and air bags on decreasing facial fractures in MVCs (n = 15,768,021, OR, 0.59, 95% CI = 0.47-0.74). Four studies were subgrouped, and a meta-analysis of these data suggested there were no significant effects of an air bag on decreasing facial fracture in MVCs (n = 15,932,259, OR, 1.00, 95% CI = 0.72-1.39).A seat belt alone (OR, 0.46) or a seat belt and an air bag (OR, 0.59) were effective to decrease facial fractures in MVCs. However, air bags alone had no significant effect (OR, 1.00). In using air bags, seat belt should be applied together to prevent facial fractures in motor vehicle injuries. PMID:26267585

  12. Triclosan antimicrobial polymers

    PubMed Central

    Petersen, Richard C.

    2016-01-01

    Triclosan antimicrobial molecular fluctuating energies of nonbonding electron pairs for the oxygen atom by ether bond rotations are reviewed with conformational computational chemistry analyses. Subsequent understanding of triclosan alternating ether bond rotations is able to help explain several material properties in Polymer Science. Unique bond rotation entanglements between triclosan and the polymer chains increase both the mechanical properties of polymer toughness and strength that are enhanced even better through secondary bonding relationships. Further, polymer blend compatibilization is considered due to similar molecular relationships and polarities. With compatibilization of triclosan in polymers a more uniform stability for nonpolar triclosan in the polymer solid state is retained by the antimicrobial for extremely low release with minimum solubility into aqueous solution. As a result, triclosan is projected for long extended lifetimes as an antimicrobial polymer additive. Further, triclosan rapid alternating ether bond rotations disrupt secondary bonding between chain monomers in the resin state to reduce viscosity and enhance polymer blending. Thus, triclosan is considered for a polymer additive with multiple properties to be an antimicrobial with additional benefits as a nonpolar toughening agent and a hydrophobic wetting agent. The triclosan material relationships with alternating ether bond rotations are described through a complete different form of medium by comparisons with known antimicrobial properties that upset bacterial cell membranes through rapid fluctuating mechanomolecular energies. Also, triclosan bond entanglements with secondary bonding can produce structural defects in weak bacterial lipid membranes requiring pliability that can then interfere with cell division. Regarding applications with polymers, triclosan can be incorporated by mixing into a resin system before cure, melt mixed with thermoplastic polymers that set on cooling

  13. Starch-based Antimicrobial Films Incorporated with Lauric Acid and Chitosan

    NASA Astrophysics Data System (ADS)

    Salleh, E.; Muhamad, I. I.

    2010-03-01

    Antimicrobial (AM) packaging is one of the most promising active packaging systems. Starch-based film is considered an economical material for antimicrobial packaging. This study aimed at the development of food packaging based on wheat starch incorporated with lauric acid and chitosan as antimicrobial agents. The purpose is to restrain or inhibit the growth of spoilage and/or pathogenic microorganisms that are contaminating foods. The antimicrobial effect was tested on B. substilis and E. coli. Inhibition of bacterial growth was examined using two methods, i.e. zone of inhibition test on solid media and liquid culture test (optical density measurements). The control and AM films (incorporated with chitosan and lauric acid) were produced by casting method. From the observations, AM films exhibited inhibitory zones. Interestingly, a wide clear zone on solid media was observed for B. substilis growth inhibition whereas inhibition for E. coli was not as effective as B. substilis. From the liquid culture test, the AM films clearly demonstrated a better inhibition against B. substilis than E. coli.

  14. Critical Compressive Stress for Flat Rectangular Plates Supported Along All Edges and Elastically Restrained Against Rotation along the Unloaded Edges

    NASA Technical Reports Server (NTRS)

    Lundquist, Eugene E; Stowell, Elbridge Z

    1942-01-01

    A chart is presented for the values of the coefficient in the formula for the critical compressive stress at which buckling may be expected to occur in flat rectangular plates supported along all edges and, in addition, elastically restrained against rotation along the unloaded edges. The mathematical derivations of the formulas required in the construction of the chart are given.

  15. Can We Prevent Antimicrobial Resistance by Using Antimicrobials Better?

    PubMed Central

    Soothill, Germander; Hu, Yanmin; Coates, Anthony

    2013-01-01

    Since their development over 60 years ago, antimicrobials have become an integral part of healthcare practice worldwide. Recently, this has been put in jeopardy by the emergence of widespread antimicrobial resistance, which is one of the major problems facing modern medicine. In the past, the development of new antimicrobials kept us one step ahead of the problem of resistance, but only three new classes of antimicrobials have reached the market in the last thirty years. A time is therefore approaching when we may not have effective treatment against bacterial infections, particularly for those that are caused by Gram-negative organisms. An important strategy to reduce the development of antimicrobial resistance is to use antimicrobials more appropriately, in ways that will prevent resistance. This involves a consideration of the pharmacokinetic and pharmacodynamics properties of antimicrobials, the possible use of combinations, and more appropriate choice of antimicrobials, which may include rapid diagnostic testing and antimicrobial cycling. Examples given in this review include Mycobacterium tuberculosis, Gram-negative and Gram-positive organisms. We shall summarise the current evidence for these strategies and outline areas for future development. PMID:25437042

  16. Substandard/Counterfeit Antimicrobial Drugs

    PubMed Central

    Kelesidis, Theodoros

    2015-01-01

    SUMMARY Substandard/counterfeit antimicrobial drugs are a growing global problem. The most common substandard/counterfeit antimicrobials include beta-lactams (among antibiotics) and chloroquine and artemisin derivatives (among antimalarials). The most common type of substandard/counterfeit antimicrobial drugs have a reduced amount of the active drug, and the majority of them are manufactured in Southeast Asia and Africa. Counterfeit antimicrobial drugs may cause increased mortality and morbidity and pose a danger to patients. Here we review the literature with regard to the issue of substandard/counterfeit antimicrobials and describe the prevalence of this problem, the different types of substandard/counterfeit antimicrobial drugs, and the consequences for the individuals and global public health. Local, national, and international initiatives are required to combat this very important public health issue. PMID:25788516

  17. Antimicrobial Resistance in Agriculture

    PubMed Central

    Thanner, Sophie; Drissner, David

    2016-01-01

    ABSTRACT In this article, the current knowledge and knowledge gaps in the emergence and spread of antimicrobial resistance (AMR) in livestock and plants and importance in terms of animal and human health are discussed. Some recommendations are provided for generation of the data required in order to develop risk assessments for AMR within agriculture and for risks through the food chain to animals and humans. PMID:27094336

  18. Antimicrobial polypeptide multilayer nanocoatings.

    PubMed

    Rudra, Jai S; Dave, Komal; Haynie, Donald T

    2006-01-01

    A multilayer coating (or film) of nanometer-thick layers can be made by sequential adsorption of oppositely charged polyelectrolytes on a solid support. The method is known as layer-by-layer assembly (LBL). No special apparatus is required for LBL and nanofilms can be prepared under mild, physiological conditions. A multilayer nanofilm in which at least one of the constituent species is a polypeptide is a polypeptide multilayer nanofilm. The present work was aimed at assessing whether polypeptide multilayer nanofilms with specific antimicrobial properties could be prepared by incorporation of a known antimicrobial agent in the film structure, in this case the edible protein hen egg white lysozyme (HEWL). The chicken enzyme is widely employed as a human food preservative. An advantage of LBL in this context is that the nanofilm is fabricated directly on the surface of interest, eliminating the need to incorporate the antimicrobial in other packaging materials. Here, nanofilms were made of poly(L-glutamic acid) (PLGA), which is highly negatively charged in the mildly acidic pH range, and HEWL, which has a high net positive charge at acidic pH. We show that PLGA/HEWL nanofilms inhibit growth of the model microbe Microccocus luteus in the surrounding liquid medium. The amount of HEWL released from PLGA/HEWL films depends on the number of HEWL layers and therefore on the total quantity of HEWL in the films. This initial study provides a sketch of the scope for further development of LBL in the area of antimicrobial polypeptide multilayer films. Potential applications of such films include strategies for food preservation and coatings for implant devices. PMID:17176751

  19. Motor Vehicle Crash–Related Injury Causation Scenarios for Spinal Injuries in Restrained Children and Adolescents

    PubMed Central

    ZONFRILLO, MARK R.; LOCEY, CAITLIN M.; SCARFONE, STEVEN R.; ARBOGAST, KRISTY B.

    2016-01-01

    Objective Motor vehicle crash (MVC)-related spinal injuries result in significant morbidity and mortality in children. The objective was to identify MVC-related injury causation scenarios for spinal injuries in restrained children. Methods This was a case series of occupants in MVCs from the Crash Injury Research and Engineering Network (CIREN) data set. Occupants aged 0–17 years old with at least one Abbreviated Injury Scale (AIS) 2+ severity spinal injury in vehicles model year 1990+ that did not experience a rollover were included. Unrestrained occupants, those not using the shoulder portion of the belt restraint, and those with child restraint gross misuse were excluded. Occupants with preexisting comorbidities contributing to spinal injury and occupants with limited injury information were also excluded. A multidisciplinary team retrospectively reviewed each case to determine injury causation scenarios (ICSs). Crash conditions, occupant and restraint characteristics, and injuries were qualitatively summarized. Results Fifty-nine cases met the study inclusion criteria and 17 were excluded. The 42 occupants included sustained 97 distinct AIS 2+ spinal injuries (27 cervical, 22 thoracic, and 48 lumbar; 80 AIS-2, 15 AIS-3, 1 AIS-5, and 1 AIS-6), with fracture as the most common injury type (80%). Spinal-injured occupants were most frequently in passenger cars (64%), and crash direction was most often frontal (62%). Mean delta-V was 51.3 km/h ± 19.4 km/h. The average occupant age was 12.4 ± 5.3 years old, and 48% were 16- to 17-year-olds. Thirty-six percent were right front passengers and 26% were drivers. Most occupants were lap and shoulder belt restrained (88%). Non-spinal AIS 2+ injuries included those of the lower extremity and pelvis (n = 56), head (n = 43), abdomen (n = 39), and thorax (n = 36). Spinal injury causation was typically due to flexion or lateral bending over the lap and or shoulder belt or child restraint harness, compression by occupant

  20. Assessment of Prone Positioning of Restrained, Seated Crewmembers in a Post Landing Stable 2 Orion Configuration

    NASA Technical Reports Server (NTRS)

    Barr, Yael; Fogarty, Jennifer

    2010-01-01

    During the Orion landing and recovery subsystem design review, June 2009, it was noted that the human system and various vehicle systems, the environmental control and life support (ECLSS) and guidance, navigation and control (GN&C) systems for example, are negatively affected by Orion assuming a stable 2 (upside down; Figure A) configuration post landing. The stable 2 configuration is predicted to occur about 50% of the time based on Apollo landing data and modeling of the current capsule. The stable 2 configuration will be countered by an active up-righting system (crew module up-righting system; CMUS). Post landing balloons will deploy and inflate causing the vehicle to assume or maintain the stable 1 (up-right; Figure B) configuration. During the design review it was proposed that the up-righting system could be capable of righting the vehicle within 60 seconds. However, this time limit posed a series of constraints on the design which made it less robust than desired. The landing and recovery subsystem team requested an analysis of Orion vehicle systems as well as the human system with regard to the effect of stable 2 in order to determine if an up-righting response time greater than 60 seconds could be tolerated. The following report focuses on the assessment of the human system in the posture assumed when Orion is in the stable 2 configuration. Stable 2 will place suited, seated, and restrained crewmembers in a prone (facedown), head-up position for a period of time dependent on the functionality of the up-righting systems, ability of the crew to release themselves from the seat and restraints, and/or time to arrival of rescue forces. Given that the Orion seat and restraint system design is not complete and therefore, not available for evaluation, Space Medicine assessed how long a healthy but deconditioned crewmember could stay in this prone, restrained position and the physiological consequences of this posture by researching terrestrial analogs and

  1. Buckling Behavior of Long Anisotropic Plates Subjected to Fully Restrained Thermal Expansion

    NASA Technical Reports Server (NTRS)

    Nemeth, Michael P.

    2003-01-01

    An approach for synthesizing buckling results and behavior for thin, balanced and unbalanced symmetric laminates that are subjected to uniform heating or cooling and which are fully-restrained against thermal expansion or contraction is presented. This approach uses a nondimensional analysis for infinitely long, flexurally anisotropic plates that are subjected to combined mechanical loads and is based on useful nondimensional parameters. In addition, stiffness-weighted laminate thermal-expansion parameters are derived and used to determine critical temperature changes in terms of physically intuitive mechanical buckling coefficients. The effects of membrane orthotropy and anisotropy are included. Many results are presented for some common laminates that are intended to facilitate a structural designer's transition to the use of the generic buckling design curves that are presented in the paper. Several generic buckling design curves are presented that provide physical insight into buckling response and provide useful design data. Examples are presented that demonstrate the use of generic design curves. The analysis approach and generic results indicate the effects and characteristics of laminate thermal expansion, membrane orthotropy and anisotropy, and flexural orthotropy and anisotropy in a very general, unifying manner.

  2. A Novel Restraining Device for Small Animal Imaging Exams: Validation in Rabbits

    PubMed Central

    Barbosa, Carlos Henrique; Carvalho, Antonio Carlos; de Souza, Sérgio; Machado, Fernanda; Guedes, Fábio; Monteiro, André; Schanaider, Alberto

    2015-01-01

    Objective. To develop, validate, and patent a Restraining Device for Small Animal Imaging Exams (RDSAIE) that allows exams to be comfortably conducted without risks to animals and professionals. Methods. A RDSAIE with a mobile cover and shelf was built with transparent acrylic material. A total of six anesthetized rabbits were used to perform the following imaging exams of the skull: Cone Beam Computed Tomography, Magnetic Resonance Imaging, and Scintigraphy. Results. The device showed great functionality and full visibility of the animal behavior, which remained fully stabilized and immobilized in either the horizontal or vertical position without the need for a person to remain in the test room to assist them. The procedures were performed without difficulty, and images of good resolution and without artifacts were obtained. Conclusion. The RDSAIE is comfortable, safe, efficient, and ergonomic. It allows the easy placement of animals in different body positions, including the vertical, the maintenance of postural stability, and full visibility. It may be constructed for animals heavier than 4 kg and it is adaptable for translational studies in anima nobile. PMID:26114109

  3. Uterine Prx2 restrains decidual differentiation through inhibiting lipolysis in mice.

    PubMed

    Jiang, Yufei; Kong, Shuangbo; He, Bo; Wang, Bingyan; Wang, Haibin; Lu, Jinhua

    2016-08-01

    Uterine decidualization, characterized as extensive stromal cell proliferation, differentiation and polyploidization, is a crucial event for successful pregnancy and is tightly regulated by many different molecules and pathways. Prx2, an evolutionarily conserved homeobox transcription factor expressed in both embryos and adults, plays an important role during mesenchymal cell differentiation. However, it remains unclear what the exact function of Prx2 is in the uterine stromal cells, one type of mesenchymal cells. In the present study, employing in vivo and in vitro stromal cell decidualization models, combining adenovirus-mediated overexpression of Prx2, we found that the expression of Prx2 is initiated in the uterine stromal cells once the blastocyst attached to the epithelium and is always detected around the differentiated decidual zone in the anti-mesometrium of the uterus during post-implantation uterine development. Also, overexpression of Prx2 disturbed stromal-decidual differentiation, which is reflected by the decreased expression of decidual/trophoblast prolactin-related protein (Dtprp), the marker for uterine decidualization in mice. Further, we demonstrate that Prx2 overexpression disturbs lipolysis, leading to lipid droplets accumulation in uterine stromal cells, partially mediated by downregulated expression of adipocyte triglyceride lipase. Collectively, these data indicate that uterine Prx2 restrains uterine decidual differentiation through regulating lipid metabolism. PMID:26987819

  4. Proline oxidase–adipose triglyceride lipase pathway restrains adipose cell death and tissue inflammation

    PubMed Central

    Lettieri Barbato, D; Aquilano, K; Baldelli, S; Cannata, S M; Bernardini, S; Rotilio, G; Ciriolo, M R

    2014-01-01

    The nutrient-sensing lipolytic enzyme adipose triglyceride lipase (ATGL) has a key role in adipose tissue function, and alterations in its activity have been implicated in many age-related metabolic disorders. In adipose tissue reduced blood vessel density is related to hypoxia state, cell death and inflammation. Here we demonstrate that adipocytes of poorly vascularized enlarged visceral adipose tissue (i.e. adipose tissue of old mice) suffer from limited nutrient delivery. In particular, nutrient starvation elicits increased activity of mitochondrial proline oxidase/dehydrogenase (POX/PRODH) that is causal in triggering a ROS-dependent induction of ATGL. We demonstrate that ATGL promotes the expression of genes related to mitochondrial oxidative metabolism (peroxisome proliferator-activated receptor-α, peroxisome proliferator-activated receptor-γ coactivator-1α), thus setting a metabolic switch towards fat utilization that supplies energy to starved adipocytes and prevents cell death, as well as adipose tissue inflammation. Taken together, these results identify ATGL as a stress resistance mediator in adipocytes, restraining visceral adipose tissue dysfunction typical of age-related metabolic disorders. PMID:24096872

  5. Apoptosis is triggered when prosurvival Bcl-2 proteins cannot restrain Bax.

    PubMed

    Fletcher, Jamie I; Meusburger, Sarina; Hawkins, Christine J; Riglar, David T; Lee, Erinna F; Fairlie, W Douglas; Huang, David C S; Adams, Jerry M

    2008-11-25

    A central issue in the control of apoptosis is whether its essential mediators Bax and Bak must be restrained by Bcl-2-like prosurvival relatives to prevent their damaging mitochondria and unleashing apoptosis. The issue is particularly vexed for Bax, which is largely a cytosolic monomer in unstressed cells. To determine whether Bax regulation requires its binding by prosurvival relatives, we replaced a conserved aspartate in its BH3 interaction domain with arginine. Bax D68R functioned and behaved like wild-type Bax in localization and activation but had greatly impaired binding to the prosurvival family members. Nevertheless, Bcl-x(L) remained able to block apoptosis induced by Bax D68R. Whereas cells with sufficient Bcl-x(L) tolerated expression of Bax D68R, it provoked apoptosis when Bcl-x(L) was absent, downregulated, or inactivated. Moreover, Bax D68R rendered membrane bound by a C-terminal anchor mutation overwhelmed endogenous Bcl-x(L) and killed cells. These unexpected results suggest that engagement of Bax by its prosurvival relatives is a major barrier to its full activation. We propose that the Bcl-2-like proteins must capture the small proportion of Bax molecules with an exposed BH3 domain, probably on the mitochondrial membrane, to prevent Bax-imposed cell death, but that Bcl-x(L) also controls Bax by other mechanisms. PMID:18981409

  6. Early age damage quantification of actively restrained concrete using inverse analysis

    NASA Astrophysics Data System (ADS)

    Albanna, Ali

    Early-age cracking can be a significant problem in concrete pavements, floors, and bridge decks. Cracking occurs when the volumetric changes associated with drying, hydration, and temperature reduction are prevented. Good knowledge about the characteristics of early age concrete is necessary to achieve reliable crack control. Volumetric changes due to shrinkage depend on the type of concrete and its components. It has been found that light weight aggregates can work as internal reservoir to supply the concrete matrix with water that is needed during the early age; this process is called internal curing. Also fibers can give more ductility to the concrete and produce less shrinkage. There is a need to better understand the effects of early age uniaxial restraint on long term concrete mechanical performance. In this study, two types of concrete were studied (high performance fiber reinforced concrete and ordinary concrete) under actively restrained loading conditions to assess the effect on the long term fracture toughness and energy. Single edge notched specimens having dimensions of 250 mm x 150 mm x 75 mm and a notch to depth ratio of 0.33 were caste and used in both direct tension and three point bending. The direct tension tests were carried out on a direct tension loading frame constructed in house that was supplied with two mechanical jacks and load cell.

  7. A Long Noncoding RNA lincRNA-EPS Acts as a Transcriptional Brake to Restrain Inflammation.

    PubMed

    Atianand, Maninjay K; Hu, Wenqian; Satpathy, Ansuman T; Shen, Ying; Ricci, Emiliano P; Alvarez-Dominguez, Juan R; Bhatta, Ankit; Schattgen, Stefan A; McGowan, Jason D; Blin, Juliana; Braun, Joerg E; Gandhi, Pallavi; Moore, Melissa J; Chang, Howard Y; Lodish, Harvey F; Caffrey, Daniel R; Fitzgerald, Katherine A

    2016-06-16

    Long intergenic noncoding RNAs (lincRNAs) are important regulators of gene expression. Although lincRNAs are expressed in immune cells, their functions in immunity are largely unexplored. Here, we identify an immunoregulatory lincRNA, lincRNA-EPS, that is precisely regulated in macrophages to control the expression of immune response genes (IRGs). Transcriptome analysis of macrophages from lincRNA-EPS-deficient mice, combined with gain-of-function and rescue experiments, revealed a specific role for this lincRNA in restraining IRG expression. Consistently, lincRNA-EPS-deficient mice manifest enhanced inflammation and lethality following endotoxin challenge in vivo. lincRNA-EPS localizes at regulatory regions of IRGs to control nucleosome positioning and repress transcription. Further, lincRNA-EPS mediates these effects by interacting with heterogeneous nuclear ribonucleoprotein L via a CANACA motif located in its 3' end. Together, these findings identify lincRNA-EPS as a repressor of inflammatory responses, highlighting the importance of lincRNAs in the immune system. PMID:27315481

  8. Buckling Of Long Compression-Loaded Anisotropic Plates Restrained Against Inplane Lateral and Shear Deformations

    NASA Technical Reports Server (NTRS)

    Nemeth, Michael P.

    2003-01-01

    An approach for synthesizing buckling results and behavior for thin balanced and unbalanced symmetric laminates that are subjected to uniform axial compression loads and elastically restrained against inplane expansion, contraction, and shear deformation is presented. This approach uses a nondimensional analysis for infinitely long, flexurally anisotropic plates (coupling between bending and twisting) that are subjected to combined mechanical loads and is based on nondimensional parameters. In addition, nondimensional loading parameters are derived that account for the effects of the elastic inplane deformation restraints, membrane orthotropy, and membrane anisotropy on the induced prebuckling stress state. The loading parameters are used to determine buckling coefficients that include the effects of flexural orthotropy and flexural anisotropy. Many results are presented, for some selected laminates, that are intended to facilitate a structural designer's transition to the use of the generic buckling design curves that are presented and discussed in the paper. Several buckling response curves are presented that provide physical insight into the behavior for combined loads, in addition to providing useful design data. An example is presented that demonstrates the use of the generic design curves, which are applicable to a wide range of laminate constructions. The analysis approach and generic results indicate the effects and characteristics of laminate orthotropy and anisotropy in a very general and unifying manner.

  9. A DELLA in Disguise: SPATULA Restrains the Growth of the Developing Arabidopsis Seedling[C][W

    PubMed Central

    Josse, Eve-Marie; Gan, Yinbo; Bou-Torrent, Jordi; Stewart, Kelly L.; Gilday, Alison D.; Jeffree, Christopher E.; Vaistij, Fabián E.; Martínez-García, Jaime F.; Nagy, Ferenc; Graham, Ian A.; Halliday, Karen J.

    2011-01-01

    The period following seedling emergence is a particularly vulnerable stage in the plant life cycle. In Arabidopsis thaliana, the phytochrome-interacting factor (PIF) subgroup of basic-helix-loop-helix transcription factors has a pivotal role in regulating growth during this early phase, integrating environmental and hormonal signals. We previously showed that SPATULA (SPT), a PIF homolog, regulates seed dormancy. In this article, we establish that unlike PIFs, which mainly promote hypocotyl elongation, SPT is a potent regulator of cotyledon expansion. Here, SPT acts in an analogous manner to the gibberellin-dependent DELLAs, REPRESSOR OF GA1-3 and GIBBERELLIC ACID INSENSITIVE, which restrain cotyledon expansion alongside SPT. However, although DELLAs are not required for SPT action, we demonstrate that SPT is subject to negative regulation by DELLAs. Cross-regulation of SPT by DELLAs ensures that SPT protein levels are limited when DELLAs are abundant but rise following DELLA depletion. This regulation provides a means to prevent excessive growth suppression that would result from the dual activity of SPT and DELLAs, yet maintain growth restraint under DELLA-depleted conditions. We present evidence that SPT and DELLAs regulate common gene targets and illustrate that the balance of SPT and DELLA action depends on light quality signals in the natural environment. PMID:21478445

  10. Whiplash-type neck distortion in restrained car drivers: frequency, causes and long-term results.

    PubMed

    Richter, M; Otte, D; Pohlemann, T; Krettek, C; Blauth, M

    2000-04-01

    An analysis was made of 1176 whiplash-type neck distortions taken from a total of 3838 restrained car driver incident reports. The percentage of whiplash-type neck distortion among injured drivers increased from less than 10% in 1985 to over 30% in 1997. Most occurred in head-on crashes or crashes with multiple collisions; only 15% occurred in rear-end collisions. More than 1,000 questionnaires were sent to the injured to find out about the duration and type of complaints caused by their cervical spine injury. Although only 138 (12%) returned the questionnaire, which may not be a representative sample, a further analysis was carried out. Of the 138, 121 (88%) indicated that they had suffered or were still suffering from their symptoms. The percentages of the various complaints were as follows: pain (74%), tension (6%) and stiffness (5%) in the head (27%), neck (55%) and shoulder (8%). The duration of the complaints was longest after multiple collisions and when the onset of complaints was longer than 24 h after trauma. Women and elderly persons predominated slightly in the group with longer duration of complaints. A correlation between the severity of the accompanying injuries and duration of complaints was found. Lack of adequate follow-up for patients with less severe injuries posed considerable difficulties for this retrospective study. In order to better evaluate this problem, prospective studies are necessary, with documentation including diagnosis, treatments, complaint duration and type. PMID:10823426

  11. Arabidopsis cryptochrome-1 restrains lateral roots growth by inhibiting auxin transport.

    PubMed

    Zeng, Jianxin; Wang, Qiming; Lin, Jianzhong; Deng, Keqin; Zhao, Xiaoying; Tang, Dongying; Liu, Xuanming

    2010-05-15

    Cryptochromes are blue-light photoreceptors that control many aspects of plant development. In this study, cryptochrome mutants of Arabidopsis were examined to assess the role of cryptchrome-1 (CRY1) in lateral roots growth. When grown in blue light for 12d, mutant seedlings (cry1) showed increased growth of lateral roots, while CRY1-overexpressing transgenic seedlings (CRY1ox) exhibited a marked decrease. Lateral roots growth of CRY1ox could be stimulated by auxin, but expression of PIN1 (efflux carrier of polar auxin transport) was strongly reduced. Contrary, the cry1 mutation showed the opposite effect, indicating that blue light and the auxin-signaling pathway interact in lateral roots growth of Arabidopsis. The free IAA content in CRY1ox roots was half of that in wild type and cry1 mutant roots. Moreover, the content of flavonoids (quercetin, kaempferol, isorhamnetin), which act as endogenous negative regulators of auxin transport, increased in CRY1ox seedlings. Taken together, these results suggest that Arabidopsis CRY1 restrains lateral roots growth by inhibiting auxin transport. PMID:20133010

  12. An oligodeoxynucleotide with CCT repeats restrains CpG ODN-induced TLR9 trafficking.

    PubMed

    Zhang, Xiaoling; Sun, Wei; Wu, Xiuli; Wang, Hua; Yan, Youyou; Guo, Sheng; Song, Dandan; Li, Hainan; Gao, Shuang; Wang, Luowei; Yu, Yongli; Wang, Liying

    2014-01-01

    Toll-like receptor 9 (TLR9) can sense pathogen DNA and CpG ODN or even self-DNA by trafficking assisted by Unc93B1, an endoplasmic reticulum (ER) transmembrane protein, from ER to endolysosomes or cell surface. In previous study, we found that an oligodeoxynucleotide with CCT repeats (SAT05f) could selectively inhibit TLR7/9 activation. However, the mechanism for the inhibitory activity of SAT05f is still unknown. In present research, it was found that SAT05f could inhibit CpG ODN-induced the intracellular trafficking of TLR9 and Unc93B1 with feedback the responses of decreased surface TLR9 and enhanced TLR9 mRNA expression but not influence TLR9 protein level by using human plasmacytoid dendritic cell line CAL-1 cells, suggesting that SAT05f inhibits TLR9 activation by restraining TLR9 trafficking. Since the mitochondrial DNA released from injured tissue can cause systemic inflammatory response syndrome (SIRS), this study may provide valuable data for prevention and treatment of SIRS and rescue severe trauma patients. PMID:25374030

  13. CD82 Restrains Angiogenesis by Altering Lipid Raft Clustering and CD44 Trafficking in Endothelial Cells

    PubMed Central

    Wei, Quan; Zhang, Feng; Richardson, Mekel M.; Roy, Nathan H.; Rodgers, William; Liu, Yuechueng; Zhao, Wenyuan; Fu, Chenying; Ding, Yingjun; Huang, Chao; Chen, Yuanjian; Sun, Yao; Ding, Lexi; Hu, Yang; Ma, Jianxing; Boulton, Michael E.; Pasula, Satish; Wren, Jonathan D.; Tanaka, Satoshi; Huang, Xiaolin; Thali, Markus; Hämmerling, Günter J.; Zhang, Xin A.

    2014-01-01

    Background Angiogenesis is crucial for many pathological processes and becomes a therapeutic strategy against diseases ranging from inflammation to cancer. The regulatory mechanism of angiogenesis remains unclear. Although tetraspanin CD82 is widely expressed in various endothelial cells (ECs), its vascular function is unknown. Methods and Results Angiogenesis was examined in Cd82-null mice with in vivo and ex vivo morphogenesis assays. Cellular functions, molecular interactions, and signaling were analyzed in Cd82-null ECs. Angiogenic responses to various stimuli became markedly increased upon Cd82 ablation. Major changes of Cd82-null ECs were enhanced migration and invasion, likely resulting from the upregulated expression of cell adhesion molecules (CAMs) such as CD44 and integrins at the cell surface and subsequently elevated outside-in signaling. Gangliosides, lipid raft clustering, and CD44-membrane microdomain interactions were increased in the plasma membrane of Cd82-null ECs, leading to less clathrin-independent endocytosis and then more surface presence of CD44. Conclusions Our study reveals that CD82 restrains pathological angiogenesis by inhibiting EC movement, lipid raft clustering and CAM trafficking modulate angiogenic potential, and the perturbation of CD82-ganglioside-CD44 signaling attenuates angiogenesis. PMID:25149363

  14. DNA methylation restrains transposons from adopting a chromatin signature permissive for meiotic recombination

    PubMed Central

    Zamudio, Natasha; Barau, Joan; Teissandier, Aurélie; Walter, Marius; Borsos, Maté; Servant, Nicolas; Bourc'his, Déborah

    2015-01-01

    DNA methylation is essential for protecting the mammalian germline against transposons. When DNA methylation-based transposon control is defective, meiotic chromosome pairing is consistently impaired during spermatogenesis: How and why meiosis is vulnerable to transposon activity is unknown. Using two DNA methylation-deficient backgrounds, the Dnmt3L and Miwi2 mutant mice, we reveal that DNA methylation is largely dispensable for silencing transposons before meiosis onset. After this, it becomes crucial to back up to a developmentally programmed H3K9me2 loss. Massive retrotransposition does not occur following transposon derepression, but the meiotic chromatin landscape is profoundly affected. Indeed, H3K4me3 marks gained over transcriptionally active transposons correlate with formation of SPO11-dependent double-strand breaks and recruitment of the DMC1 repair enzyme in Dnmt3L−/− meiotic cells, whereas these features are normally exclusive to meiotic recombination hot spots. Here, we demonstrate that DNA methylation restrains transposons from adopting chromatin characteristics amenable to meiotic recombination, which we propose prevents the occurrence of erratic chromosomal events. PMID:26109049

  15. Buckling Behavior of Long Anisotropic Plates Subjected to Fully Restrained Thermal Expansion

    NASA Technical Reports Server (NTRS)

    Nemeth, Michael P.

    2001-01-01

    An approach for synthesizing buckling results and behavior for thin balanced and unbalanced symmetric laminates that are subjected to uniform heating or cooling and fully restrained against thermal expansion or contraction is presented. This approach uses a nondimensional analysis for infinitely long, flexurally anisotropic plates that are subjected to combined mechanical loads and is based on useful nondimensional parameters. In addition, stiffness-weighted laminate thermal-expansion parameters are derived that are used to determine critical temperatures in terms of physically intuitive mechanical buckling coefficients, and the effects of membrane orthotropy and membrane anisotropy are included. Many results are presented for some common laminates that are intended to facilitate a structural designer's transition to the use of the generic buckling design curves that are presented in the paper. Several generic buckling design curves are presented that provide physical insight into the buckling response in addition to providing useful design data. Examples are presented that demonstrate the use of the generic design curves. The analysis approach and generic results indicate the effects and characteristics of laminate thermal expansion, membrane orthotropy and anisotropy, and flexural orthotropy and anisotropy in a very general and unifying manner.

  16. Spontaneous regional brain activity links restrained eating to later weight gain among young women.

    PubMed

    Dong, Debo; Jackson, Todd; Wang, Yulin; Chen, Hong

    2015-07-01

    Theory and prospective studies have linked restrained eating (RE) to risk for future weight gain and the onset of obesity, but little is known about resting state neural activity that may underlie this association. To address this gap, resting fMRI was used to test the extent to which spontaneous neural activity in regions associated with inhibitory control and food reward account for potential relations between baseline RE levels and changes in body weight among dieters over a one-year interval. Spontaneous regional activity patterns corresponding to RE were assessed among 50 young women using regional homogeneity (ReHo) analysis, which measured temporal synchronization of spontaneous fluctuations within a food deprivation condition. Analyses indicated higher baseline RE scores predicted more weight gain at a one-year follow-up. Furthermore, food-deprived dieting women with high dietary restraint scores exhibited more spontaneous local activity in brain regions associated with the expectation and valuation for food reward [i.e., orbitofrontal cortex (OFC)/ventromedial prefrontal cortex (VMPFC)] and reduced spontaneous local activity in inhibitory control regions [i.e., bilateral dorsal-lateral prefrontal cortex (DLPFC)] at baseline. Notably, the association between baseline RE and follow-up weight gain was mediated by decreased local synchronization of the right DLPFC in particular and, to a lesser degree, increased local synchronization of the right VMPFC. In conjunction with previous research, these findings highlight possible neural mechanisms underlying the relation between RE and risk for weight gain. PMID:26004091

  17. Engineering Antimicrobials Refractory to Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multi-drug resistant superbugs are a persistent problem in modern health care, demonstrating the need for a new class of antimicrobials that can address this concern. Triple-acting peptidoglycan hydrolase fusions are a novel class of antimicrobials which have qualities well suited to avoiding resis...

  18. Conformationally restrained analogs of sympathomimetic catecholamines. Synthesis, conformational analysis, and adrenergic activity of isochroman derivatives.

    PubMed

    Macchia, B; Balsamo, A; Breschi, M C; Chiellini, G; Lapucci, A; Macchia, M; Manera, C; Martinelli, A; Martini, C; Scatizzi, R

    1993-10-15

    In previous papers dealing with the study of the conformations and the biopharmacological activity of conformationally restrained analogs of sympathomimetic catecholamines (NE and ISO), proposals were advanced for the three-dimensional molecular models A, B, and C; these models provided information about the steric requirements for the direct activation of alpha 1, alpha 2,beta 1, and beta 2 adrenoceptors, respectively. The 1-(aminomethyl)-6,7-dihydroxyisochromans 11 and 12 and the 1-(aminomethyl)-5,6-dihydroxyisochromans 13 and 14 (1-AMDICs) are two different types of semirigid analogs of NE and ISO. The alpha 1, alpha 2, beta 1, and beta 2 adrenergic properties of the 1-AMDICs 11-14 were evaluated in vitro, both by radioligand binding assays and by functional tests on isolated preparations, and were compared with those of their parent compounds (NE and ISO). The results of a conformational study carried out by means of both 1H NMR spectrometry and theoretical calculations indicated that, in these 1-AMDICs, the presumed active groups (aryl moiety, amine nitrogen and benzylic ethereal oxygen) are in a spatial relationship corresponding to the one found for NE and ISO in their preferred conformations, which also proved to be the pharmacophoric conformation in the models A-C. By means of a comparison of the stereostructures of the 1-AMDICs 11-14 with their biopharmacological properties, it was possible to obtain a further definition of the model B with respect to the activation of the alpha 2 adrenoceptors; the superimposition of the 1-AMDICs 11 and 12 with the molecular model C made it possible to detect an area of the beta-adrenergic receptors which might hinder the fit of adrenergic drugs that are analogs of catecholamines with these receptors. PMID:8230093

  19. Restraining non-specific adsorption of protein using Parylene C-caulked polydimethylsiloxane.

    PubMed

    Liu, Yaoping; Zhang, Lingqian; Wu, Wengang; Zhao, Meiping; Wang, Wei

    2016-03-01

    Non-specific adsorption (NSA) of proteins on surface is a critical issue in polydimethylsiloxane (PDMS)-based microfluidics, which may either considerably decrease the efficiency of a continuous flow reaction or cause a large background noise in a heterogeneous sensing. This work introduced a new method to restrain NSA of protein by caulking PDMS with Parylene C, i.e., forming a Parylene C-caulked PDMS (pcPDMS) surface. The caulking depth of Parylene C inside PDMS matrix was characterized by laser scanning confocal microscopy based on a detectable autofluorescence intensity difference between Parylene C and PDMS after being annealed at 270 °C for 2 h in nitrogen. NSA of bovine serum albumin (BSA) on the inner surfaces of PDMS and pcPDMS microchannels was experimentally compared. The results indicated that the adsorbed BSA on the pcPDMS surface were 35.2% of that on the pristine PDMS surface after the BSA solution flowing through the microchannels at a flow rate of 2000 nL/min, a typical scenario of the continuous flow reaction. In a case mimicking the heterogeneous sensing, after a 60 min washing of phosphate buffered saline flow on a pre-saturated BSA adsorbed surface, the residual BSA on the pcPDMS surface was only 4.5% of that on the pristine PDMS surface. Adsorption/desorption coefficients of BSA on the PDMS and the pcPDMS surfaces were extracted from the experimental results based on the first-order Langmuir model, which indicated that the pcPDMS has a lower adsorption coefficient (Ka ) and a higher desorption coefficient (Kd ), compared to those of the pristine PDMS. A preliminary experiment also indicated that Taq polymerase kept 93.0% activity after flowing through a pcPDMS microchannel, while only 28.9% activity was left after passing a pristine PDMS microchannel under the same operation condition. PMID:27158294

  20. Prostate Cancer Induced by Loss of Apc Is Restrained by TGFβ Signaling

    PubMed Central

    Bjerke, Glen A.; Pietrzak, Karolina; Melhuish, Tiffany A.; Frierson Jr., Henry F.; Paschal, Bryce M.; Wotton, David

    2014-01-01

    Recent work with mouse models of prostate cancer (CaP) has shown that inactivation of TGFβ signaling in prostate epithelium can cooperate with deletion of the Pten tumor suppressor to drive locally aggressive cancer and metastatic disease. Here, we show that inactivating the TGFβ pathway by deleting the gene encoding the TGFβ type II receptor (Tgfbr2) in combination with a deletion of the Apc tumor suppressor gene specifically in mouse prostate epithelium, results in the rapid onset of invasive CaP. Micro-metastases were observed in the lymph nodes and lungs of a proportion of the double mutant mice, whereas no metastases were observed in Apc single mutant mice. Prostate-specific Apc;Tgfbr2 mutants had a lower frequency of metastasis and survived significantly longer than Pten;Tgfbr2 double mutants. However, all Apc;Tgfbr2 mutants developed invasive cancer by 30 weeks of age, whereas invasive cancer was rarely observed in Apc single mutant animals, even by one year of age. Further comparison of the Pten and Apc models of CaP revealed additional differences, including adenosquamous carcinoma in the Apc;Tgfbr2 mutants that was not seen in the Pten model, and a lack of robust induction of the TGFβ pathway in Apc null prostate. In addition to causing high-grade prostate intra-epithelial neoplasia (HGPIN), deletion of either Pten or Apc induced senescence in affected prostate ducts, and this restraint was overcome by loss of Tgfbr2. In summary, this work demonstrates that TGFβ signaling restrains the progression of CaP induced by different tumor suppressor mutations, suggesting that TGFβ signaling exerts a general tumor suppressive effect in prostate. PMID:24651496

  1. Dendritic cell-bound IgE functions to restrain allergic inflammation at mucosal sites

    PubMed Central

    Platzer, Barbara; Baker, Kristi; Vera, Miguel Pinilla; Singer, Kathleen; Panduro, Marisella; Lexmond, Willem S.; Turner, Devin; Vargas, Sara O.; Kinet, Jean-Pierre; Maurer, Dieter; Baron, Rebecca M.; Blumberg, Richard S.; Fiebiger, Edda

    2014-01-01

    Antigen-mediated crosslinking of Immunoglobulin E (IgE) bound to mast cells/basophils via FcεRI, the high affinity IgE Fc-receptor, is a well-known trigger of allergy. In humans, but not mice, dendritic cells (DCs) also express FcεRI that is constitutively occupied with IgE. In contrast to mast cells/basophils, the consequences of IgE/FcεRI signals for DC function remain poorly understood. We show that humanized mice that express FcεRI on DCs carry IgE like non-allergic humans and do not develop spontaneous allergies. Antigen-specific IgE/FcεRI crosslinking fails to induce maturation or production of inflammatory mediators in human DCs and FcεRI-humanized DCs. Furthermore, conferring expression of FcεRI to DCs decreases the severity of food allergy and asthma in disease-relevant models suggesting anti-inflammatory IgE/FcεRI signals. Consistent with the improved clinical parameters in vivo, antigen-specific IgE/FcεRI crosslinking on papain or LPS-stimulated DCs inhibits the production of pro-inflammatory cytokines and chemokines. Migration assays confirm that the IgE-dependent decrease in cytokine production results in diminished recruitment of mast cell progenitors; providing a mechanistic explanation for the reduced mast cell-dependent allergic phenotype observed in FcεRI-humanized mice. Our study demonstrates a novel immune regulatory function of IgE and proposes that DC-intrinsic IgE signals serve as a feedback mechanism to restrain allergic tissue inflammation. PMID:25227985

  2. The adaptive immune system restrains Alzheimer's disease pathogenesis by modulating microglial function.

    PubMed

    Marsh, Samuel E; Abud, Edsel M; Lakatos, Anita; Karimzadeh, Alborz; Yeung, Stephen T; Davtyan, Hayk; Fote, Gianna M; Lau, Lydia; Weinger, Jason G; Lane, Thomas E; Inlay, Matthew A; Poon, Wayne W; Blurton-Jones, Mathew

    2016-03-01

    The innate immune system is strongly implicated in the pathogenesis of Alzheimer's disease (AD). In contrast, the role of adaptive immunity in AD remains largely unknown. However, numerous clinical trials are testing vaccination strategies for AD, suggesting that T and B cells play a pivotal role in this disease. To test the hypothesis that adaptive immunity influences AD pathogenesis, we generated an immune-deficient AD mouse model that lacks T, B, and natural killer (NK) cells. The resulting "Rag-5xfAD" mice exhibit a greater than twofold increase in β-amyloid (Aβ) pathology. Gene expression analysis of the brain implicates altered innate and adaptive immune pathways, including changes in cytokine/chemokine signaling and decreased Ig-mediated processes. Neuroinflammation is also greatly exacerbated in Rag-5xfAD mice as indicated by a shift in microglial phenotype, increased cytokine production, and reduced phagocytic capacity. In contrast, immune-intact 5xfAD mice exhibit elevated levels of nonamyloid reactive IgGs in association with microglia, and treatment of Rag-5xfAD mice or microglial cells with preimmune IgG enhances Aβ clearance. Last, we performed bone marrow transplantation studies in Rag-5xfAD mice, revealing that replacement of these missing adaptive immune populations can dramatically reduce AD pathology. Taken together, these data strongly suggest that adaptive immune cell populations play an important role in restraining AD pathology. In contrast, depletion of B cells and their appropriate activation by T cells leads to a loss of adaptive-innate immunity cross talk and accelerated disease progression. PMID:26884167

  3. Estradiol Restrains Prepubertal Gonadotropin Secretion in Female Mice via Activation of ERα in Kisspeptin Neurons.

    PubMed

    Dubois, Sharon L; Wolfe, Andrew; Radovick, Sally; Boehm, Ulrich; Levine, Jon E

    2016-04-01

    Elimination of estrogen receptorα (ERα) from kisspeptin (Kiss1) neurons results in premature LH release and pubertal onset, implicating these receptors in 17β-estradiol (E2)-mediated negative feedback regulation of GnRH release during the prepubertal period. Here, we tested the dependency of prepubertal negative feedback on ERα in Kiss1 neurons. Prepubertal (postnatal d 14) and peripubertal (postnatal d 34) wild-type (WT) and Kiss1 cell-specific ERα knockout (KERαKO) female mice were sham operated or ovariectomized and treated with either vehicle- or E2-containing capsules. Plasma and tissues were collected 2 days after surgery for analysis. Ovariectomy increased LH and FSH levels, and E2 treatments completely prevented these increases in WT mice of both ages. However, in prepubertal KERαKO mice, basal LH levels were elevated vs WT, and both LH and FSH levels were not further increased by ovariectomy or affected by E2 treatment. Similarly, Kiss1 mRNA levels in the medial basal hypothalamus, which includes the arcuate nucleus, were suppressed with E2 treatment in ovariectomized prepubertal WT mice but remained unaffected by any treatment in KERαKO mice. In peripubertal KERαKO mice, basal LH and FSH levels were not elevated vs WT and were unaffected by ovariectomy or E2. In contrast to our previous findings in adult animals, these results demonstrate that suppression of gonadotropins and Kiss1 mRNA by E2 in prepubertal animals depends upon ERα activation in Kiss1 neurons. Our observations are consistent with the hypothesis that these receptors play a critical role in restraining GnRH release before the onset and completion of puberty. PMID:26824364

  4. The adaptive immune system restrains Alzheimer’s disease pathogenesis by modulating microglial function

    PubMed Central

    Abud, Edsel M.; Lakatos, Anita; Karimzadeh, Alborz; Yeung, Stephen T.; Davtyan, Hayk; Fote, Gianna M.; Lau, Lydia; Weinger, Jason G.; Lane, Thomas E.; Inlay, Matthew A.; Poon, Wayne W.; Blurton-Jones, Mathew

    2016-01-01

    The innate immune system is strongly implicated in the pathogenesis of Alzheimer’s disease (AD). In contrast, the role of adaptive immunity in AD remains largely unknown. However, numerous clinical trials are testing vaccination strategies for AD, suggesting that T and B cells play a pivotal role in this disease. To test the hypothesis that adaptive immunity influences AD pathogenesis, we generated an immune-deficient AD mouse model that lacks T, B, and natural killer (NK) cells. The resulting “Rag-5xfAD” mice exhibit a greater than twofold increase in β-amyloid (Aβ) pathology. Gene expression analysis of the brain implicates altered innate and adaptive immune pathways, including changes in cytokine/chemokine signaling and decreased Ig-mediated processes. Neuroinflammation is also greatly exacerbated in Rag-5xfAD mice as indicated by a shift in microglial phenotype, increased cytokine production, and reduced phagocytic capacity. In contrast, immune-intact 5xfAD mice exhibit elevated levels of nonamyloid reactive IgGs in association with microglia, and treatment of Rag-5xfAD mice or microglial cells with preimmune IgG enhances Aβ clearance. Last, we performed bone marrow transplantation studies in Rag-5xfAD mice, revealing that replacement of these missing adaptive immune populations can dramatically reduce AD pathology. Taken together, these data strongly suggest that adaptive immune cell populations play an important role in restraining AD pathology. In contrast, depletion of B cells and their appropriate activation by T cells leads to a loss of adaptive–innate immunity cross talk and accelerated disease progression. PMID:26884167

  5. Antimicrobial activity of antiproteinases.

    PubMed

    Sallenave, J M

    2002-04-01

    Low-molecular-mass neutrophil elastase inhibitors have been shown to be important in the control of lung inflammation. In addition to inhibiting the enzyme neutrophil elastase, these low-molecular-mass compounds (10 kDa) have been shown to have other activities. For example, secretory leucocyte proteinase inhibitor (SLPI) and elastase-specific inhibitor/SKALP (skin-derived antileucoproteinase)/elafin have also been shown to have "defensin"-like antimicrobial activities. Indeed, these inhibitors have antimicrobial properties in vitro against bacteria, fungi and, potentially, HIV. In addition, we have shown, using an adenovirus-mediated gene transfer overexpression strategy, that elafin is also active against Pseudomonas aeruginosa infection in mice in vivo. The mechanism of action is currently under investigation. In addition to these direct or indirect effects on microbes, it has been shown that lipopolysaccharide is able to up-regulate SPLI production in macrophages in vitro, and that the addition of recombinant SLPI to human monocytes or the transfection of macrophages with SPLI can down-regulate pro-inflammatory mediators such as tumour necrosis factor, presumably to limit self-damaging excessive inflammation. Using viral gene transfer vectors, we are currently investigating the potential of these inhibitors in various models of inflammation in vivo. PMID:12023836

  6. Antimicrobial Mechanism of Monocaprylate

    PubMed Central

    Hyldgaard, Morten; Sutherland, Duncan S.; Sundh, Maria; Mygind, Tina

    2012-01-01

    Monoglyceride esters of fatty acids occur naturally and encompass a broad spectrum of antimicrobial activity. Monocaprylate is generally regarded as safe (GRAS) and can function both as an emulsifier and as a preservative in food. However, knowledge about its mode of action is lacking. The aim of this study was therefore to elucidate the mechanism behind monocaprylate's antimicrobial effect. The cause of cell death in Escherichia coli, Staphylococcus xylosus, and Zygosaccharomyces bailii was investigated by examining monocaprylate's effect on cell structure, membrane integrity, and its interaction with model membranes. Changes in cell structure were visible by atomic force microscopy (AFM), and propidium iodide staining showed membrane disruption, indicating the membrane as a site of action. This indication was confirmed by measuring calcein leakage from membrane vesicles exposed to monocaprylate. AFM imaging of supported lipid bilayers visualized the integration of monocaprylate into the liquid disordered, and not the solid ordered, phase of the membrane. The integration of monocaprylate was confirmed by quartz crystal microbalance measurements, showing an abrupt increase in mass and hydration of the membrane after exposure to monocaprylate above a threshold concentration. We hypothesize that monocaprylate destabilizes membranes by increasing membrane fluidity and the number of phase boundary defects. The sensitivity of cells to monocaprylate will therefore depend on the lipid composition, fluidity, and curvature of the membrane. PMID:22344642

  7. The Relationship between Antimicrobial Use and Antimicrobial Resistance in Europe

    PubMed Central

    Cars, Otto; Buchholz, Udo; Mölstad, Sigvard; Goettsch, Wim; Veldhuijzen, Irene K.; Kool, Jacob L.; Sprenger, Marc J.W.; Degener, John E.

    2002-01-01

    In Europe, antimicrobial resistance has been monitored since 1998 by the European Antimicrobial Resistance Surveillance System (EARSS). We examined the relationship between penicillin nonsusceptibility of invasive isolates of Streptococcus pneumoniae (an indicator organism) and antibiotic sales. Information was collected on 1998-99 resistance data for invasive isolates of S. pneumoniae to penicillin, based on surveillance data from EARSS and on outpatient sales during 1997 for beta-lactam antibiotics and macrolides. Our results show that in Europe antimicrobial resistance is correlated with use of beta-lactam antibiotics and macrolides. PMID:11927025

  8. Novel Formulations for Antimicrobial Peptides

    PubMed Central

    Carmona-Ribeiro, Ana Maria; Carrasco, Letícia Dias de Melo

    2014-01-01

    Peptides in general hold much promise as a major ingredient in novel supramolecular assemblies. They may become essential in vaccine design, antimicrobial chemotherapy, cancer immunotherapy, food preservation, organs transplants, design of novel materials for dentistry, formulations against diabetes and other important strategical applications. This review discusses how novel formulations may improve the therapeutic index of antimicrobial peptides by protecting their activity and improving their bioavailability. The diversity of novel formulations using lipids, liposomes, nanoparticles, polymers, micelles, etc., within the limits of nanotechnology may also provide novel applications going beyond antimicrobial chemotherapy. PMID:25302615

  9. Antimicrobial properties of diacetyl.

    PubMed Central

    Jay, J M

    1982-01-01

    Diacetyl preparations from three commercial sources were found to be essentially similar when tested primarily against a set of 40 cultures, including 10 of lactic acid bacteria, 4 of yeasts, 12 of gram-positive non-lactic acid bacteria, and 14 of gram-negative bacteria. The compound was effective at pH less than or equal to 7.0 and progressively ineffective at pH greater than 7.0. The lactic acid bacteria were essentially unaffected by concentrations between 100 and 350 micrograms/ml over the pH range of 5.0 to 7.0. Of the 12 gram-positive non-lactic acid bacteria, 11 were inhibited by 300 micrograms/ml at pH less than or equal to 7.0. The three yeasts and the 13 gram-negative bacteria that grew at pH 5.5 were inhibited by 200 micrograms/ml. Diacetyl was ineffective against four clostridia under anaerobic conditions. It was lethal for gram-negative bacteria and generally inhibitory for gram-positive bacteria. Nongrowing cells were not affected. The effectiveness of diacetyl was considerably less in brain heart infusion broth, Trypticase soy agar, and cooked-meat medium than in nutrient broth or plate count agar. The antimicrobial activity was antagonized by glucose, acetate, and Tween 80 but not by gluconic acid. As an antimicrobial agent, diacetyl was clearly more effective against gram-negative bacteria, yeasts, and molds than against gram-positive bacteria. PMID:7137998

  10. A nanobody targeting the F-actin capping protein CapG restrains breast cancer metastasis

    PubMed Central

    2013-01-01

    Introduction Aberrant turnover of the actin cytoskeleton is intimately associated with cancer cell migration and invasion. Frequently however, evidence is circumstantial, and a reliable assessment of the therapeutic significance of a gene product is offset by lack of inhibitors that target biologic properties of a protein, as most conventional drugs do, instead of the corresponding gene. Proteomic studies have demonstrated overexpression of CapG, a constituent of the actin cytoskeleton, in breast cancer. Indirect evidence suggests that CapG is involved in tumor cell dissemination and metastasis. In this study, we used llama-derived CapG single-domain antibodies or nanobodies in a breast cancer metastasis model to address whether inhibition of CapG activity holds therapeutic merit. Methods We raised single-domain antibodies (nanobodies) against human CapG and used these as intrabodies (immunomodulation) after lentiviral transduction of breast cancer cells. Functional characterization of nanobodies was performed to identify which biochemical properties of CapG are perturbed. Orthotopic and tail vein in vivo models of metastasis in nude mice were used to assess cancer cell spreading. Results With G-actin and F-actin binding assays, we identified a CapG nanobody that binds with nanomolar affinity to the first CapG domain. Consequently, CapG interaction with actin monomers or actin filaments is blocked. Intracellular delocalization experiments demonstrated that the nanobody interacts with CapG in the cytoplasmic environment. Expression of the nanobody in breast cancer cells restrained cell migration and Matrigel invasion. Notably, the nanobody prevented formation of lung metastatic lesions in orthotopic xenograft and tail-vein models of metastasis in immunodeficient mice. We showed that CapG nanobodies can be delivered into cancer cells by using bacteria harboring a type III protein secretion system (T3SS). Conclusions CapG inhibition strongly reduces breast cancer

  11. Force Measurement Using Non-Restrained Models In A Shock Tunnel

    NASA Astrophysics Data System (ADS)

    Tanno, Hideyuki; Sato, Kazuo; Komuro, Tomoyuki; Takahashi, Massahiro; Itoh, Katsuhiro; Fujita, Kazuhisa; Laurence, Stuart; Hannemann, Klaus

    2011-05-01

    A novel force measurement technique has been developed at the impulsive facility HIEST, in which the test model is completely non-restrained for the duration of the test, so it experiences free-flight conditions for a period on the order of milliseconds. This technique was demonstrated with a three-component aerodynamic force measurement with a blunted cone of total length 318 mm and a total mass of 22 kg. At the beginning of the wind tunnel test, the blunted cone test model was suspended from electromagnets fixed on the test-section ceiling. The model was released when a triggering signal arrived from the tunnel start signal. The model then fell so that it met the hypersonic test flow just as it arrived in the test section, and made a soft landing on a model catcher with four hydraulic shock absorbers. A miniature model-onboard data-logger, which was a key technology for this technique, was also developed in order to store the measured data. The data-logger was designed to be small enough to be instrumented in test models, with an overall size of 50 mm x 70 mm x 50 mm, including batteries. Since the logger was designed to measure force and pressure, it includes six piezoelectric amplifiers and four piezoresistive amplifiers, as well as high-speed analog-digital converters, which digitize the measured data with 16-bit resolution. The logger’s sampling rate and sample size are 500 kHz and 200 ms, respectively. The logger waits for a trigger signal (accelerometer output) and then starts to take measurements. The trigger threshold and pre-trigger delay time can be adjusted arbitrarily. Measured data is stored to static memory for transfer to a PC via a USB interface after a wind tunnel test. To demonstrate the entire measurement system, wind tunnel experiments were conducted in HIEST. In the present wind tunnel test campaign, records of pressure and axial force were obtained under conditions of H0 = 4 MJ/kg, P0 = 14 MPa. This demonstrated that the system worked

  12. Attitudes towards child restrains and seat belts usage in the learned population of Karachi, Pakistan

    PubMed Central

    Siddiqui, Emaduddin; Ejaz, Kiran; Waheed, Shahan; Kazi, Ghazala Irfan; Khursheed, Munawar

    2014-01-01

    BACKGROUND: Motor vehicles crashes (MVCs) are the leading cause of injury related morbidity and mortality in developed countries. Recent evidence proves that properly used child seat belts can dramatically reduce the risk of severe and life-threatening injury from MVCs. There are rarities of thought and inspiration regarding the use of child seat belts in our society and region, therefore we lack of data regarding factors and paucity of usage of child seat belts in motor vehicles. This study aimed to assess the knowledge and attitudes of child seat belt usage among the educated population in Karachi, Pakistan. METHODS: Altogether 304 employees were investigated. They were employees of Aga Khan University who were using their cars and having children younger than 10 years old. A cross sectional observational study was designed, and a 36-item questionnaire in English was used to collect data on participants’ demographic details, designation, educational level, economic status, validity of driving license, number of children and cars, availability of adult seat belts and child seat belts along with their functionality, awareness, knowledge and attitude toward its use, and reason of not using these devices. SPSS version 20 for Windows was used to analyze the data and the Chi-square test was used. RESULTS: Totally 290 participants were recruited with a response rate of 72% (212). Of 212 participants, 126 (59%) were male. 154 (72.6%) participants had valid driver licenses, and 154 (72.6%) had adult seat belts in their vehicles. Only 32 (15%) reported regular use of adult seat belts. Although 168 (79.2%) participants had some knowledge about child restrains (CRs), only 65 (22%) had CRs in their cars. Eighty-two (38.7%) participants got the knowledge about CRs and seat belts from media. Mothers were more concerned about the use of CRs than fathers. Only 14 (6.6%) parents were found to use both adult and child seat belts all the time. Of the 157 parents who did not us use

  13. Antimicrobials therapy of anaerobic infections.

    PubMed

    Brook, Itzhak

    2016-06-01

    Anaerobes predominant in the normal human skin and mucous membranes bacterial flora are often a cause of endogenous infections. Anaerobic bacteria are difficult to isolate from infectious sites, and are often overlooked. Anaerobic infections caused by anaerobes can occur in all body sites, including the central nervous system (CNS), oral cavity, head and neck, chest, abdomen, pelvis, skin and soft tissues. The treatment of these infections is complicated by the slow growth of these organisms, their polymicrobial nature and the growing resistance of anaerobes to antimicrobials agents. Antimicrobials are frequently the only form of therapy needed, but in others, they are an important adjunct to surgical drainage and correction of pathology. Because anaerobes are often recovered with aerobic and facultative bacteria, the chosen antimicrobials should cover all pathogens. The antimicrobials effective against anaerobic organisms are metronidazole, carbapenems, combinations of a beta-lactam and a beta-lactamase inhibitor, chloramphenicol, tigecycline and clindamycin. PMID:26365224

  14. Automation of antimicrobial activity screening.

    PubMed

    Forry, Samuel P; Madonna, Megan C; López-Pérez, Daneli; Lin, Nancy J; Pasco, Madeleine D

    2016-03-01

    Manual and automated methods were compared for routine screening of compounds for antimicrobial activity. Automation generally accelerated assays and required less user intervention while producing comparable results. Automated protocols were validated for planktonic, biofilm, and agar cultures of the oral microbe Streptococcus mutans that is commonly associated with tooth decay. Toxicity assays for the known antimicrobial compound cetylpyridinium chloride (CPC) were validated against planktonic, biofilm forming, and 24 h biofilm culture conditions, and several commonly reported toxicity/antimicrobial activity measures were evaluated: the 50 % inhibitory concentration (IC50), the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC). Using automated methods, three halide salts of cetylpyridinium (CPC, CPB, CPI) were rapidly screened with no detectable effect of the counter ion on antimicrobial activity. PMID:26970766

  15. Antimicrobial seafood packaging: a review.

    PubMed

    Singh, Suman; Ho Lee, Myung; Park, Lnsik; Shin, Yangjai; Lee, Youn Suk

    2016-06-01

    Microorganisms are the major cause of spoilage in most seafood products; however, only few microbes, called the specific spoilage organisms (SSOs), contribute to the offensive off-flavors associated with seafood spoilage. In food, microbial degradation manifests itself as spoilage, or changes in the sensory properties of a food product, rendering it unsuitable for human consumption. The use of antimicrobial substances can control the general microflora as well as specific microorganisms related to spoilage to provide products with higher safety and better quality. Many antimicrobial compounds have been evaluated in film structures for use in seafood, especially organic acids and their salts, enzymes, bacteriocins; some studies have considered inorganic compounds such as AgSiO2, zinc oxide, silver zeolite, and titanium oxide. The characteristics of some organic antimicrobial packaging systems for seafood and their antimicrobial efficiency in film structures are reviewed in this article. PMID:27478206

  16. Associations between Restrained Eating and the Size and Frequency of Overall Intake, Meal, Snack and Drink Occasions in the UK Adult National Diet and Nutrition Survey

    PubMed Central

    Olea López, Ana Lorena; Johnson, Laura

    2016-01-01

    Obesity is a global public health priority. Restrained eating is related to obesity and total energy intake but associations with the eating patterns are unclear. We examined the associations of restrained eating with the size and frequency of intake occasions among 1213 British adult (19–64 y) participants in a cross-sectional analysis of the UK National Diet and Nutrition Survey 2000. The Dutch Eating Behaviour Questionnaire assessed restrained eating. Overall intake occasions were all energy consumed in a 60 min period. A food-based classification separated intake occasions into meals, snacks, or drinks from seven-day weighed food diaries. Average daily frequency and size (kcal) of overall intake, meal, snack and drink occasions were calculated and associations with restrained eating were modelled using multiple linear regression including under-reporting of energy intake, age, gender, BMI, emotional eating, external eating and physical activity as covariates. Restrained eating was very weakly positively correlated with overall intake (r = 0.08, p<0.05) and meal frequency (r = 0.10, p<0.05) but not snack or drink frequency (r = 0.02 and -0.02 respectively). Adjusted regressions showed a one-point change in restrained eating was associated with 0.07 (95% CI 0.03, 0.11) more meal occasions/day and 0.13 (95% CI 0.01, 0.25) extra overall intake occasions/day. Overall intake occasion size was weakly negatively correlated with restrained eating regardless of type (r = -0.16 to -0.20, all p<0.0001). Adjusted regressions showed each one-point increase in restrained eating was associated with lower-energy meals (-15 kcal 95% CI -5.9, -24.2) and drinks (-4 kcal 95%CI -0.1, -8), but not snacks or overall intake occasions. Among a national sample of UK adults, greater restrained eating was associated with smaller and slightly more frequent eating, suggesting that restrained eaters restrict their energy intake by reducing meal/drink size rather than skipping snacks. PMID

  17. Antimicrobial Stewardship Programs in Health Care Systems

    PubMed Central

    MacDougall, Conan; Polk, Ron E.

    2005-01-01

    Antimicrobial stewardship programs in hospitals seek to optimize antimicrobial prescribing in order to improve individual patient care as well as reduce hospital costs and slow the spread of antimicrobial resistance. With antimicrobial resistance on the rise worldwide and few new agents in development, antimicrobial stewardship programs are more important than ever in ensuring the continued efficacy of available antimicrobials. The design of antimicrobial management programs should be based on the best current understanding of the relationship between antimicrobial use and resistance. Such programs should be administered by multidisciplinary teams composed of infectious diseases physicians, clinical pharmacists, clinical microbiologists, and infection control practitioners and should be actively supported by hospital administrators. Strategies for changing antimicrobial prescribing behavior include education of prescribers regarding proper antimicrobial usage, creation of an antimicrobial formulary with restricted prescribing of targeted agents, and review of antimicrobial prescribing with feedback to prescribers. Clinical computer systems can aid in the implementation of each of these strategies, especially as expert systems able to provide patient-specific data and suggestions at the point of care. Antibiotic rotation strategies control the prescribing process by scheduled changes of antimicrobial classes used for empirical therapy. When instituting an antimicrobial stewardship program, a hospital should tailor its choice of strategies to its needs and available resources. PMID:16223951

  18. Transcranial Two-Photon Imaging of Synaptic Structures in the Cortex of Awake Head-Restrained Mice

    PubMed Central

    Yang, Guang; Pan, Feng; Chang, Paul C.; Gooden, Frank; Gan, Wen-Biao

    2013-01-01

    Transcranial two-photon microscopy allows long-term imaging of neurons, glia, and vasculature in the intact cortex of living animals. So far, this technique has been primarily used to acquire images in anesthetized animals. Here, we describe a detailed protocol for high-resolution two-photon imaging of neuronal structures in the cortex of awake head-restrained mice. Surgery is done within 1 h in anesthetized mice. After animals recover from anesthesia, two-photon imaging can be performed multiple times over minutes to days, allowing longitudinal studies of synaptic plasticity and pathology without the complication induced by anesthesia reagents. PMID:23754217

  19. Critical combinations of shear and transverse direct stress for an infinitely long flat plate with edges elastically restrained against rotation

    NASA Technical Reports Server (NTRS)

    Batdorf, S B; Houbolt, John C

    1946-01-01

    An exact solution and a closely concurring approximate energy solution are given for the buckling of an infinitely long flat plate under combined shear and transverse direct stress with edges elastically restrained against rotation. It was found that an appreciable fraction of the critical stress in pure shear may be applied to the plate without any reduction in the transverse compressive stress necessary to produce buckling. An interaction formula in general use was shown to be decidedly conservative for the range in which it is supposed to apply.

  20. Large deflection random response of cross-ply laminated plates with elastically restrained edges and initial imperfections

    NASA Technical Reports Server (NTRS)

    Prasad, C. B.; Mei, Chuh

    1988-01-01

    The large deflection random response of symmetrically laminated cross-ply rectangular thin plates subjected to random excitation is studied. The out-of-plane boundary conditions are such that all the edges are rigidly supported against translation, but elastically restrained against rotation. The plate is also assumed to have a small initial imperfection. The assumed membrane boundary conditions are such that all the edges are free from normal and tangential forces in the plane of the plate. Mean-square deflections and mean-square strains are determined for a three-layered cross-ply laminate.

  1. Study Under AC Stimulation on Excitement Properties of Weighted Small-World Biological Neural Networks with Side-Restrain Mechanism

    NASA Astrophysics Data System (ADS)

    Yuan, Wu-Jie; Luo, Xiao-Shu; Jiang, Pin-Qun

    2007-02-01

    In this paper, we propose a new model of weighted small-world biological neural networks based on biophysical Hodgkin-Huxley neurons with side-restrain mechanism. Then we study excitement properties of the model under alternating current (AC) stimulation. The study shows that the excitement properties in the networks are preferably consistent with the behavior properties of a brain nervous system under different AC stimuli, such as refractory period and the brain neural excitement response induced by different intensities of noise and coupling. The results of the study have reference worthiness for the brain nerve electrophysiology and epistemological science.

  2. Editorial of the Special Issue Antimicrobial Polymers

    PubMed Central

    Piozzi, Antonella; Francolini, Iolanda

    2013-01-01

    The special issue “Antimicrobial Polymers” includes research and review papers concerning the recent advances on preparation of antimicrobial polymers and their relevance to industrial settings and biomedical field. Antimicrobial polymers have recently emerged as promising candidates to fight microbial contamination onto surfaces thanks to their interesting properties. In this special issue, the main strategies pursued for developing antimicrobial polymers, including polymer impregnation with antimicrobial agents or synthesis of polymers bearing antimicrobial moieties, were discussed. The future application of these polymers either in industrial or healthcare settings could result in an extremely positive impact not only at the economic level but also for the improvement of quality of life. PMID:24005863

  3. Peptides and Peptidomimetics for Antimicrobial Drug Design

    PubMed Central

    Mojsoska, Biljana; Jenssen, Håvard

    2015-01-01

    The purpose of this paper is to introduce and highlight a few classes of traditional antimicrobial peptides with a focus on structure-activity relationship studies. After first dissecting the important physiochemical properties that influence the antimicrobial and toxic properties of antimicrobial peptides, the contributions of individual amino acids with respect to the peptides antibacterial properties are presented. A brief discussion of the mechanisms of action of different antimicrobials as well as the development of bacterial resistance towards antimicrobial peptides follows. Finally, current efforts on novel design strategies and peptidomimetics are introduced to illustrate the importance of antimicrobial peptide research in the development of future antibiotics. PMID:26184232

  4. Focusing on media body ideal images triggers food intake among restrained eaters: a test of restraint theory and the elaboration likelihood model.

    PubMed

    Boyce, Jessica A; Kuijer, Roeline G

    2014-04-01

    Although research consistently shows that images of thin women in the media (media body ideals) affect women negatively (e.g., increased weight dissatisfaction and food intake), this effect is less clear among restrained eaters. The majority of experiments demonstrate that restrained eaters - identified with the Restraint Scale - consume more food than do other participants after viewing media body ideal images; whereas a minority of experiments suggest that such images trigger restrained eaters' dietary restraint. Weight satisfaction and mood results are just as variable. One reason for these inconsistent results might be that different methods of image exposure (e.g., slideshow vs. film) afford varying levels of attention. Therefore, we manipulated attention levels and measured participants' weight satisfaction and food intake. We based our hypotheses on the elaboration likelihood model and on restraint theory. We hypothesised that advertent (i.e., processing the images via central routes of persuasion) and inadvertent (i.e., processing the images via peripheral routes of persuasion) exposure would trigger differing degrees of weight dissatisfaction and dietary disinhibition among restrained eaters (cf. restraint theory). Participants (N = 174) were assigned to one of four conditions: advertent or inadvertent exposure to media or control images. The dependent variables were measured in a supposedly unrelated study. Although restrained eaters' weight satisfaction was not significantly affected by either media exposure condition, advertent (but not inadvertent) media exposure triggered restrained eaters' eating. These results suggest that teaching restrained eaters how to pay less attention to media body ideal images might be an effective strategy in media-literary interventions. PMID:24854816

  5. Crash characteristics and injury patterns of restrained front seat occupants in far-side impacts

    PubMed Central

    Yoganandan, Narayan; Arun, Mike W. J.; Halloway, Dale E.; Pintar, Frank A.; Maiman, Dennis J.; Szabo, Aniko; Rudd, Rodney W.

    2015-01-01

    STRUCTURED ABSTRACT Objective The study was conducted to determine the association between vehicle-, crash- and demographic-related factors and injuries to front seat far-side occupants in modern environments. Methods Field data were obtained from the United States (US) National Automotive Sampling System – Crashworthiness Data System (NASS-CDS) database, for the years 2009–2012. Inclusion factors: adult restrained front outboard seated occupants, no ejection or rollovers, and vehicle model years less than 10 years old at the time of crash. Far-side crashes were determined by using collision deformation classification. Injuries were scored using the Abbreviated Injury Scale (AIS). Injuries (MAIS2+, MAIS3+, M denotes maximum score) were examined based on demographics, change in velocity, vehicle type, direction of force, extent zone, collision partner and presence of another occupant in the front seat. Only weighted data were used in the analysis. Injuries to the head and face, thorax, abdomen, pelvis, upper extremity and lower extremity regions were studied. Odds ratios and upper and lower confidence intervals were estimated from multivariate analysis. Results Out of 519,195 far-side occupants, 17,715 were MAIS2+ and 4,387 were MAIS3+ level injured occupants. The mean age, stature, total body mass, and BMI were 40.7 years, 1.7 m, 77.2 kg, and 26.8 kg/m2, respectively. Of occupants with MAIS2+ injuries, 51% had head and 19% had thorax injuries. Of occupants with MAIS 3+ injuries, 50% had head and 69% had thorax injuries. The cumulative distribution of changes in velocities at the 50th percent level for the struck vehicle for all occupants and, MAIS2+ and MAIS3+ occupants were 19, 34 and 42 km/h, respectively. Furthermore, 73% of MAIS2+ injuries and 86% of MAIS3+ injuries occurred at a change in velocity of 24 km/h or greater. Odds of sustaining MAIS2+ and MAIS3+ injuries increased with unit increase in change in velocity, stature and age, with one exception

  6. Purification of antimicrobial peptide from Antarctic Krill ( Euphausia superba) and its function mechanism

    NASA Astrophysics Data System (ADS)

    Zhao, Ling; Yin, Bangzhong; Liu, Qi; Cao, Rong

    2013-09-01

    The preliminary purification and antimicrobial mechanism of antimicrobial peptide from Antarctic Krill were studied in this paper. The results showed that the molecular weight range of antimicrobial polypeptide (CMCC-1) obtained by cation exchange chromatography was between 245-709D as detected by molecular sieve chromatography, and the minimum inhibition concentration (MIC) of CMCC-1 against Staphylococcus aureus was 5.0 mg mL-1. The antimicrobial mechanism of CMCC-1 was studied with S. aureus as indicator bacterium. Compared with control group, the results of the experimental group in which S. aureus was treated with CMCC-1 were as follows: 1) CMCC-1 could inhibit cell division at logarithmic phase. 2) The protein and reducing sugar content, and the conductivity of culture medium increased, and the activity of alkaline phosphatase and β-galactosidase could be detected in the culture medium. 3) Observation under scanning electron microscope revealed that somatic morphology became irregular, and then somatic surface became coarse. The cell became much smaller, and most somatic cells gathered. The boundary between cells became dim and finally fused as a whole. 4) Observation under transmission electron microscope showed that the surface of S. aureus became rough and the reproducing ability was restrained. The cell wall became thin and the cytoplasm shrunk. Substances inside cell leaked out, which caused cells death. 5) SDS-PAGE analysis showed that some bands disappeared, and the residual bands became vague. 6) The genomic DNA electrophoresis results showed that the genomic DNA bands of S. aureus were not degraded but the brightness significantly reduced. Thus, it is supposed that CMCC-1 could destroy the cell wall and membrane of S. aureu, increase the cell membrane permeability and the leaking-out of intracellular substances, and thus cause the death of S. aureu.

  7. Antimicrobials in urogenital infections.

    PubMed

    Wagenlehner, Florian M E; Wullt, Björn; Perletti, Gianpaolo

    2011-12-01

    Urinary tract infections (UTIs) and male genital infections are amongst the most prevalent infections. A prudent antibiotic policy therefore has a large impact on society. The clinical classification in uncomplicated cystitis, uncomplicated pyelonephritis, complicated UTI and genital infections is useful, also for the right choice of antibiotic treatment. In this regard pharmacokinetic and pharmacodynamic aspects have to be considered. Nowadays in uncomplicated cystitis antibiotics exclusively reserved for this indication are preferred, such as fosfomycin trometamol, nitrofurantoin and pivmecillinam, in order to reduce antibiotic pressure in this extremely frequent entity. In complicated UTI a broad bacterial spectrum has to be considered. Different antibiotic substances should be used for treatment, such as penicillins, with β-lactamase inhibitors, cephalosporins or carbapenems, fluoroquinolones, aminoglycosides or cotrimoxazole, if tested susceptible. For genital infections the pharmacokinetic properties of the antibiotics should especially be considered, such as in prostatitis, where mainly fluoroquinolones and macrolides show sufficient pharmacokinetic parameters for treatment of bacterial infections. Furthermore in genital infections fastidious organisms, such as Chlamydia or Mycoplasma spp. have to be considered with respect to their antimicrobial susceptibility. PMID:22019184

  8. Synthetic antimicrobial peptide design.

    PubMed

    Powell, W A; Catranis, C M; Maynard, C A

    1995-01-01

    To guide the design of potential plant pathogen-resistance genes, synthetic variants of naturally occurring antimicrobial gene products were evaluated. Five 20-amino acid (ESF1, ESF4, ESF5, ESF6, ESF13), one 18-amino acid (ESF12), and one 17-amino acid (ESF17) amphipathic peptide sequences were designed, synthesized, and tested with in vitro bioassays. Positive charges on the hydrophilic side of the peptide were shown to be essential for antifungal activity, yet the number of positive charges could be varied with little or no change in activity. The size could be reduced to 18 amino acids, but at 17 amino acids a significant reduction in activity was observed. ESF1, 5, 6, and 12 peptides were inhibitory to the germination of conidia from Cryphonectria parasitica, Fusarium oxysporum f. sp. lycopersici, and Septoria musiva but did not inhibit the germination of pollen from Castanea mollissima and Salix lucida. ESF12 also had no effect on the germination of Malus sylvestris and Lycopersicon esculentum pollen, but inhibited the growth of the bacteria Agrobacterium tumefaciens, Erwinia amylovora, and Pseudomonas syringae. The minimal inhibitory concentrations of the active ESF peptides were similar to those of the naturally occurring control peptides, magainin II and cecropin B. The significant differential in sensitivity between the microbes and plant cells indicated that the active ESF peptides are potentially useful models for designing plant pathogen-resistance genes. PMID:7579625

  9. Antimicrobial Peptides from Plants.

    PubMed

    Tam, James P; Wang, Shujing; Wong, Ka H; Tan, Wei Liang

    2015-01-01

    Plant antimicrobial peptides (AMPs) have evolved differently from AMPs from other life forms. They are generally rich in cysteine residues which form multiple disulfides. In turn, the disulfides cross-braced plant AMPs as cystine-rich peptides to confer them with extraordinary high chemical, thermal and proteolytic stability. The cystine-rich or commonly known as cysteine-rich peptides (CRPs) of plant AMPs are classified into families based on their sequence similarity, cysteine motifs that determine their distinctive disulfide bond patterns and tertiary structure fold. Cystine-rich plant AMP families include thionins, defensins, hevein-like peptides, knottin-type peptides (linear and cyclic), lipid transfer proteins, α-hairpinin and snakins family. In addition, there are AMPs which are rich in other amino acids. The ability of plant AMPs to organize into specific families with conserved structural folds that enable sequence variation of non-Cys residues encased in the same scaffold within a particular family to play multiple functions. Furthermore, the ability of plant AMPs to tolerate hypervariable sequences using a conserved scaffold provides diversity to recognize different targets by varying the sequence of the non-cysteine residues. These properties bode well for developing plant AMPs as potential therapeutics and for protection of crops through transgenic methods. This review provides an overview of the major families of plant AMPs, including their structures, functions, and putative mechanisms. PMID:26580629

  10. Antimicrobial Peptides from Plants

    PubMed Central

    Tam, James P.; Wang, Shujing; Wong, Ka H.; Tan, Wei Liang

    2015-01-01

    Plant antimicrobial peptides (AMPs) have evolved differently from AMPs from other life forms. They are generally rich in cysteine residues which form multiple disulfides. In turn, the disulfides cross-braced plant AMPs as cystine-rich peptides to confer them with extraordinary high chemical, thermal and proteolytic stability. The cystine-rich or commonly known as cysteine-rich peptides (CRPs) of plant AMPs are classified into families based on their sequence similarity, cysteine motifs that determine their distinctive disulfide bond patterns and tertiary structure fold. Cystine-rich plant AMP families include thionins, defensins, hevein-like peptides, knottin-type peptides (linear and cyclic), lipid transfer proteins, α-hairpinin and snakins family. In addition, there are AMPs which are rich in other amino acids. The ability of plant AMPs to organize into specific families with conserved structural folds that enable sequence variation of non-Cys residues encased in the same scaffold within a particular family to play multiple functions. Furthermore, the ability of plant AMPs to tolerate hypervariable sequences using a conserved scaffold provides diversity to recognize different targets by varying the sequence of the non-cysteine residues. These properties bode well for developing plant AMPs as potential therapeutics and for protection of crops through transgenic methods. This review provides an overview of the major families of plant AMPs, including their structures, functions, and putative mechanisms. PMID:26580629

  11. Structural Dynamics and Conformational Equilibria of SERCA Regulatory Proteins in Membranes by Solid-State NMR Restrained Simulations

    PubMed Central

    De Simone, Alfonso; Mote, Kaustubh R.; Veglia, Gianluigi

    2014-01-01

    Solid-state NMR spectroscopy is emerging as a powerful approach to determine structure, topology, and conformational dynamics of membrane proteins at the atomic level. Conformational dynamics are often inferred and quantified from the motional averaging of the NMR parameters. However, the nature of these motions is difficult to envision based only on spectroscopic data. Here, we utilized restrained molecular dynamics simulations to probe the structural dynamics, topology and conformational transitions of regulatory membrane proteins of the calcium ATPase SERCA, namely sarcolipin and phospholamban, in explicit lipid bilayers. Specifically, we employed oriented solid-state NMR data, such as dipolar couplings and chemical shift anisotropy measured in lipid bicelles, to refine the conformational ensemble of these proteins in lipid membranes. The samplings accurately reproduced the orientations of transmembrane helices and showed a significant degree of convergence with all of the NMR parameters. Unlike the unrestrained simulations, the resulting sarcolipin structures are in agreement with distances and angles for hydrogen bonds in ideal helices. In the case of phospholamban, the restrained ensemble sampled the conformational interconversion between T (helical) and R (unfolded) states for the cytoplasmic region that could not be observed using standard structural refinements with the same experimental data set. This study underscores the importance of implementing NMR data in molecular dynamics protocols to better describe the conformational landscapes of membrane proteins embedded in realistic lipid membranes. PMID:24940774

  12. Resveratrol Treatment after Status Epilepticus Restrains Neurodegeneration and Abnormal Neurogenesis with Suppression of Oxidative Stress and Inflammation

    PubMed Central

    Mishra, Vikas; Shuai, Bing; Kodali, Maheedhar; Shetty, Geetha A.; Hattiangady, Bharathi; Rao, Xiaolan; Shetty, Ashok K.

    2015-01-01

    Antiepileptic drug therapy, though beneficial for restraining seizures, cannot thwart status epilepticus (SE) induced neurodegeneration or down-stream detrimental changes. We investigated the efficacy of resveratrol (RESV) for preventing SE-induced neurodegeneration, abnormal neurogenesis, oxidative stress and inflammation in the hippocampus. We induced SE in young rats and treated with either vehicle or RESV, commencing an hour after SE induction and continuing every hour for three-hours on SE day and twice daily thereafter for 3 days. Seizures were terminated in both groups two-hours after SE with a diazepam injection. In contrast to the vehicle-treated group, the hippocampus of animals receiving RESV during and after SE presented no loss of glutamatergic neurons in hippocampal cell layers, diminished loss of inhibitory interneurons expressing parvalbumin, somatostatin and neuropeptide Y in the dentate gyrus, reduced aberrant neurogenesis with preservation of reelin + interneurons, lowered concentration of oxidative stress byproduct malondialdehyde and pro-inflammatory cytokine tumor necrosis factor-alpha, normalized expression of oxidative stress responsive genes and diminished numbers of activated microglia. Thus, 4 days of RESV treatment after SE is efficacious for thwarting glutamatergic neuron degeneration, alleviating interneuron loss and abnormal neurogenesis, and suppressing oxidative stress and inflammation. These results have implications for restraining SE-induced chronic temporal lobe epilepsy. PMID:26639668

  13. Altered frontal inter-hemispheric resting state functional connectivity is associated with bulimic symptoms among restrained eaters.

    PubMed

    Chen, Shuaiyu; Dong, Debo; Jackson, Todd; Su, Yanhua; Chen, Hong

    2016-01-29

    Theory and research have indicated that restrained eating (RE) increases risk for binge-eating and eating disorder symptoms. According to the goal conflict model, such risk may result from disrupted hedonic-feeding control and its interaction with reward-driven eating. However, RE-related alterations in functional interactions among associated underlying brain regions, especially between the cerebral hemispheres, have rarely been examined directly. Therefore, we investigated inter-hemispheric resting-state functional connectivity (RSFC) among female restrained eaters (REs) (n=23) and unrestrained eaters (UREs) (n=24) following food deprivation as well as its relation to overall bulimia nervosa (BN) symptoms using voxel-mirrored homotopic connectivity (VMHC). Seed-based RSFC associated with areas exhibiting significant VMHC differences was also assessed. Compared to UREs, REs showed reduced VMHC in the dorsal-lateral prefrontal cortex (DLPFC), an area involved in inhibiting hedonic overeating. REs also displayed decreased RSFC between the right DLPFC and regions associated with reward estimation--the ventromedial prefrontal cortex (VMPFC) and posterior cingulate cortex (PCC). Finally, bulimic tendencies had a negative correlation with VMHC in the DLPFC and a positive correlation with functional connectivity (DLPFC and VMPFC) among REs but not UREs. Findings suggested that reduced inter-hemispheric functional connectivity in appetite inhibition regions and altered functional connectivity in reward related regions may help to explain why some REs fail to control hedonically-motivated feeding and experience higher associated levels of BN symptomatology. PMID:26160289

  14. Assessment of buckling-restrained braced frame reliability using an experimental limit-state model and stochastic dynamic analysis

    NASA Astrophysics Data System (ADS)

    Andrews, Blake M.; Song, Junho; Fahnestock, Larry A.

    2009-09-01

    Buckling-restrained braces (BRBs) have recently become popular in the United States for use as primary members of seismic lateral-force-resisting systems. A BRB is a steel brace that does not buckle in compression but instead yields in both tension and compression. Although design guidelines for BRB applications have been developed, systematic procedures for assessing performance and quantifying reliability are still needed. This paper presents an analytical framework for assessing buckling-restrained braced frame (BRBF) reliability when subjected to seismic loads. This framework efficiently quantifies the risk of BRB failure due to low-cycle fatigue fracture of the BRB core. The procedure includes a series of components that: (1) quantify BRB demand in terms of BRB core deformation histories generated through stochastic dynamic analyses; (2) quantify the limit-state of a BRB in terms of its remaining cumulative plastic ductility capacity based on an experimental database; and (3) evaluate the probability of BRB failure, given the quantified demand and capacity, through structural reliability analyses. Parametric studies were conducted to investigate the effects of the seismic load, and characteristics of the BRB and BRBF on the probability of brace failure. In addition, fragility curves (i.e., conditional probabilities of brace failure given ground shaking intensity parameters) were created by the proposed framework. While the framework presented in this paper is applied to the assessment of BRBFs, the modular nature of the framework components allows for application to other structural components and systems.

  15. Introduction of carbon nano-tubes into the phosphor to restrain the saturation behavior in low voltage cathodoluminescence.

    PubMed

    Shang, Chunyu; Zhao, Jinxian; Wang, Xiuqin

    2016-02-01

    To restrain the saturation behavior in low voltage cathodoluminescence, a small amount of carbon nano-tubes (CNT) was introduced into the phosphor to form CNT-introduced phosphor material. In the specific working conditions in low voltage cathodoluminescence, the field enhancement effect is initiated in the CNT-introduced phosphor material, and the local electric fields surrounding the top of each CNT is much stronger than the background electric field. The CNTs, with enhanced local electric fields surrounding their tops, play a key role in removing the electrons in the phosphor material, in which the CNTs act as convenient channels for electrons to be removed in cathodoluminescence. By introducing a small amount of CNTs into the phosphor, the saturation behavior in low voltage cathodoluminescence is effectively restrained, which has a similar effect as improving the conductivity of the phosphor material. The field enhancement effect in the CNT-introduced phosphor material may be activated and become more effective when the applied current density in cathodoluminescence is increased, thus the dynamic performance of the CNT-introduced phosphor material is favorable in low voltage cathodoluminescence. PMID:26750979

  16. Identifying Armed Respondents to Domestic Violence Restraining Orders and Recovering Their Firearms: Process Evaluation of an Initiative in California

    PubMed Central

    Frattaroli, Shannon; Claire, Barbara E.; Vittes, Katherine A.; Webster, Daniel W.

    2014-01-01

    Objectives. We evaluated a law enforcement initiative to screen respondents to domestic violence restraining orders for firearm ownership or possession and recover their firearms. Methods. The initiative was implemented in San Mateo and Butte counties in California from 2007 through 2010. We used descriptive methods to evaluate the screening process and recovery effort in each county, relying on records for individual cases. Results. Screening relied on an archive of firearm transactions, court records, and petitioner interviews; no single source was adequate. Screening linked 525 respondents (17.7%) in San Mateo County to firearms; 405 firearms were recovered from 119 (22.7%) of them. In Butte County, 88 (31.1%) respondents were linked to firearms; 260 firearms were recovered from 45 (51.1%) of them. Nonrecovery occurred most often when orders were never served or respondents denied having firearms. There were no reports of serious violence or injury. Conclusions. Recovering firearms from persons subject to domestic violence restraining orders is possible. We have identified design and implementation changes that may improve the screening process and the yield from recovery efforts. Larger implementation trials are needed. PMID:24328660

  17. Antimicrobial implications of vitamin D

    PubMed Central

    Youssef, Dima A; Miller, Christopher WT; El-Abbassi, Adel M; Cutchins, Della C; Cutchins, Coleman; Grant, William B

    2011-01-01

    Evidence exists that vitamin D has a potential antimicrobial activity and its deficiency has deleterious effects on general well-being and longevity. Vitamin D may reduce the risk of infection through multiple mechanisms. Vitamin D boosts innate immunity by modulating production of anti-microbial peptides (AMPs) and cytokine response. Vitamin D and its analogues via these mechanisms are playing an increasing role in the management of atopic dermatitis, psoriasis, vitiligo, acne and rosacea. Vitamin D may reduce susceptibility to infection in patients with atopic dermatitis and the ability to regulate local immune and inflammatory responses offers exciting potential for understanding and treating chronic inflammatory dermatitides. Moreover, B and T cell activation as well as boosting the activity of monocytes and macrophages also contribute to a potent systemic anti-microbial effect. The direct invasion by pathogenic organisms may be minimized at sites such as the respiratory tract by enhancing clearance of invading organisms. A vitamin D replete state appears to benefit most infections, with the possible noteworthy exception of Leishmaniasis. Antibiotics remain an expensive option and misuse of these agents results in significant antibiotic resistance and contributes to escalating health care costs. Vitamin D constitutes an inexpensive prophylactic option and possibly therapeutic product either by itself or as a synergistic agent to traditional antimicrobial agents. This review outlines the specific antimicrobial properties of vitamin D in combating a wide range of organisms. We discuss the possible mechanisms by which vitamin D may have a therapeutic role in managing a variety of infections. PMID:22259647

  18. Antimicrobial Resistance Mechanisms among Campylobacter

    PubMed Central

    2013-01-01

    Campylobacter jejuni and Campylobacter coli are recognized as the most common causative agents of bacterial gastroenteritis in the world. Humans most often become infected by ingesting contaminated food, especially undercooked chicken, but also other sources of bacteria have been described. Campylobacteriosis is normally a self-limiting disease. Antimicrobial treatment is needed only in patients with more severe disease and in those who are immunologically compromised. The most common antimicrobial agents used in the treatment of Campylobacter infections are macrolides, such as erythromycin, and fluoroquinolones, such as ciprofloxacin. Tetracyclines have been suggested as an alternative choice in the treatment of clinical campylobacteriosis but in practice are not often used. However, during the past few decades an increasing number of resistant Campylobacter isolates have developed resistance to fluoroquinolones and other antimicrobials such as macrolides, aminoglycosides, and beta-lactams. Trends in antimicrobial resistance have shown a clear correlation between use of antibiotics in the veterinary medicine and animal production and resistant isolates of Campylobacter in humans. In this review, the patterns of emerging resistance to the antimicrobial agents useful in treatment of the disease are presented and the mechanisms of resistance to these drugs in Campylobacter are discussed. PMID:23865047

  19. Antimicrobial activities of squalamine mimics.

    PubMed

    Kikuchi, K; Bernard, E M; Sadownik, A; Regen, S L; Armstrong, D

    1997-07-01

    We investigated the antimicrobial properties of compounds with structural features that were designed to mimic those of squalamine, an antibiotic isolated from the stomach of the dogfish shark. The mimics, like squalamine, are sterol-polyamine conjugates. Unlike squalamine, the mimics were simple to prepare, at high yield, from readily available starting materials. Several squalamine mimics showed activity against gram-negative rods, gram-positive cocci including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium, and fungi. Some had little or no hemolytic activity. The hydrophobicity of the sterol backbone and the length and the cationic charge of the side chains appeared to be critical determinants of activity. One of the squalamine mimics, SM-7, was bactericidal against Escherichia coli, Pseudomonas aeruginosa, and S. aureus; its activity was decreased by divalent or monovalent cations and by bovine serum albumin. Subinhibitory concentrations of SM-7 markedly enhanced the antimicrobial activity of rifampin against gram-negative rods. These results suggest that the compounds may disrupt an outer membrane of gram-negative rods. Squalamine mimics are a new class of broad-spectrum antimicrobial agents. The antagonism of their activity by serum and albumin and their hemolytic properties may limit their use as systemic agents. The squalamine mimics, because of their potencies, broad spectra of antimicrobial activity, and potential for systemic toxicity, appear to be good candidates for development as topical antimicrobial agents. PMID:9210661

  20. Antifungal proteins: More than antimicrobials?

    PubMed Central

    Hegedüs, Nikoletta; Marx, Florentine

    2013-01-01

    Antimicrobial proteins (AMPs) are widely distributed in nature. In higher eukaryotes, AMPs provide the host with an important defence mechanism against invading pathogens. AMPs of lower eukaryotes and prokaryotes may support successful competition for nutrients with other microorganisms of the same ecological niche. AMPs show a vast variety in structure, function, antimicrobial spectrum and mechanism of action. Most interestingly, there is growing evidence that AMPs also fulfil important biological functions other than antimicrobial activity. The present review focuses on the mechanistic function of small, cationic, cysteine-rich AMPs of mammals, insects, plants and fungi with antifungal activity and specifically aims at summarizing current knowledge concerning additional biological properties which opens novel aspects for their future use in medicine, agriculture and biotechnology. PMID:23412850

  1. Synthetic biology of antimicrobial discovery.

    PubMed

    Zakeri, Bijan; Lu, Timothy K

    2013-07-19

    Antibiotic discovery has a storied history. From the discovery of penicillin by Sir Alexander Fleming to the relentless quest for antibiotics by Selman Waksman, the stories have become like folklore used to inspire future generations of scientists. However, recent discovery pipelines have run dry at a time when multidrug-resistant pathogens are on the rise. Nature has proven to be a valuable reservoir of antimicrobial agents, which are primarily produced by modularized biochemical pathways. Such modularization is well suited to remodeling by an interdisciplinary approach that spans science and engineering. Herein, we discuss the biological engineering of small molecules, peptides, and non-traditional antimicrobials and provide an overview of the growing applicability of synthetic biology to antimicrobials discovery. PMID:23654251

  2. Antimicrobial Properties of Titanium Nanoparticles

    NASA Astrophysics Data System (ADS)

    Erdural, B. K.; Yurum, A.; Bakir, U.; Karakas, G.

    In the present study, nanostructured titania particles were synthesized using hydrothermal processing and their photocatalytic antimicrobial activities were characterized. Sol-gel synthesized TiO2 samples were treated with a two step hydrothermal treatment. The first stage treatment was the alkaline treatment with 10 M of NaOH for 48 h at 130°C, followed with the second step which applied with distilled water for 48 h at 200°C. Scanning Electron Microscope (SEM) images showed that alkaline treatment yields lamellar structure particles from the sol-gel synthesized anatase. Further treatment of nanoplates with distilled water results in crystal growth and the formation of nano structured thorn like particles. The photocatalytic antimicrobial activities of samples were determined against Escherichia coli under solar irradiation for 4 h. It was observed that the samples treated under alkaline conditions have higher antimicrobial activity than the untreated samples.

  3. Synthetic biology of antimicrobial discovery

    PubMed Central

    Zakeri, Bijan; Lu, Timothy K.

    2012-01-01

    Antibiotic discovery has a storied history. From the discovery of penicillin by Sir Alexander Fleming to the relentless quest for antibiotics by Selman Waksman, the stories have become like folklore, used to inspire future generations of scientists. However, recent discovery pipelines have run dry at a time when multidrug resistant pathogens are on the rise. Nature has proven to be a valuable reservoir of antimicrobial agents, which are primarily produced by modularized biochemical pathways. Such modularization is well suited to remodeling by an interdisciplinary approach that spans science and engineering. Herein, we discuss the biological engineering of small molecules, peptides, and non-traditional antimicrobials and provide an overview of the growing applicability of synthetic biology to antimicrobials discovery. PMID:23654251

  4. Antimicrobial susceptibility of Mycoplasma hyorhinis.

    PubMed

    Wu, C C; Shryock, T R; Lin, T L; Faderan, M; Veenhuizen, M F

    2000-09-15

    A broth microdilution technique was used to determine the antimicrobial susceptibility of 15 field isolates of Mycoplasma hyorhinis to 10 antimicrobial agents, representative of different classes, and contrasting newer agents to existing ones. For the macrolides, the MIC(90) for tylosin and tilmicosin was 1 and 4 microg/ml, respectively, but was > or = 16 microg/ml for erythromycin. Tetracycline, lincomycin and enrofloxacin each had an MIC(90) of 2 microg/ml. The mycoplasma had similar levels of susceptibility to the aminoglycoside and aminocyclictol classes exhibiting an MIC(90) of 4 microg/ml for gentamicin and 2 microg/ml for spectinomycin. The isolates exhibited high MICs to trimethoprim/sulfamethoxazole with an MIC(90) > or = 16/304 microg/ml. In summary, M. hyorhinis isolates from the US had low MICs against a variety of antimicrobials tested, with the exception of erythromycin and trimethoprim/sulfamethoxazole. PMID:10925038

  5. Uses of antimicrobial genes from microbial genome

    DOEpatents

    Sorek, Rotem; Rubin, Edward M.

    2013-08-20

    We describe a method for mining microbial genomes to discover antimicrobial genes and proteins having broad spectrum of activity. Also described are antimicrobial genes and their expression products from various microbial genomes that were found using this method. The products of such genes can be used as antimicrobial agents or as tools for molecular biology.

  6. Fluoroquinolone antimicrobial agents.

    PubMed Central

    Wolfson, J S; Hooper, D C

    1989-01-01

    The fluoroquinolones, a new class of potent orally absorbed antimicrobial agents, are reviewed, considering structure, mechanisms of action and resistance, spectrum, variables affecting activity in vitro, pharmacokinetic properties, clinical efficacy, emergence of resistance, and tolerability. The primary bacterial target is the enzyme deoxyribonucleic acid gyrase. Bacterial resistance occurs by chromosomal mutations altering deoxyribonucleic acid gyrase and decreasing drug permeation. The drugs are bactericidal and potent in vitro against members of the family Enterobacteriaceae, Haemophilus spp., and Neisseria spp., have good activity against Pseudomonas aeruginosa and staphylococci, and (with several exceptions) are less potent against streptococci and have fair to poor activity against anaerobic species. Potency in vitro decreases in the presence of low pH, magnesium ions, or urine but is little affected by different media, increased inoculum, or serum. The effects of the drugs in combination with a beta-lactam or aminoglycoside are often additive, occasionally synergistic, and rarely antagonistic. The agents are orally absorbed, require at most twice-daily dosing, and achieve high concentrations in urine, feces, and kidney and good concentrations in lung, bone, prostate, and other tissues. The drugs are efficacious in treatment of a variety of bacterial infections, including uncomplicated and complicated urinary tract infections, bacterial gastroenteritis, and gonorrhea, and show promise for therapy of prostatitis, respiratory tract infections, osteomyelitis, and cutaneous infections, particularly when caused by aerobic gram-negative bacilli. Fluoroquinolones have also proved to be efficacious for prophylaxis against travelers' diarrhea and infection with gram-negative bacilli in neutropenic patients. The drugs are effective in eliminating carriage of Neisseria meningitidis. Patient tolerability appears acceptable, with gastrointestinal or central nervous

  7. Comparative study of choleretic agents in anesthetized rats as well as in restrained and and unrestrained rats, with or without compensation for biliary loss

    NASA Technical Reports Server (NTRS)

    Labrid, C.; Dureng, G.; Tachon, J.; Duchene-Marullaz, P.

    1980-01-01

    Tests were conducted on Wistar rats by using 3 control choleretic agents: 1-phenyl-1-hydroxy n-pentane, dehydrocholic acid, and phenyl-dimethylacetic acid. The effects of these agents were compared in different experimental conditions. The comparative study of choleretic agents in anesthetized rats, in restrained and unrestrained rats, with or without compensation for biliary loss by the biliary secretion of restrained or unrestrained rats does not show, in systematic pharmecodynamic investigations, an obvious superiority over the methods based on the simple technique.

  8. How antimicrobial peptides disrupt lipid bilayers?

    NASA Astrophysics Data System (ADS)

    Sengupta, Durba

    2011-03-01

    The molecular basis for the activity of cyclic and linear antimicrobial peptides is analysed. We performed multi-scale molecular dynamics simulations and biophysical measurements to probe the interaction of antimicrobial peptides with model membranes. Two linear antimicrobial peptides, magainin and melittin and a cyclic one, BPC194 have been studied. We test different models to determine the generic and specific forces that lead to bilayer disruption. We probe whether interfacial stress or local membrane perturbation is more likely to lead to the porated state. We further analyse the reasons that determine specificity and increase of activity in antimicrobial peptides. The results provide detailed insight in the mode of action of antimicrobial peptides.

  9. Antimicrobial food packaging in meat industry.

    PubMed

    Quintavalla, Stefania; Vicini, Loredana

    2002-11-01

    Antimicrobial packaging, an active packaging concept, can be considered an extremely challenging technology that could have a significant impact on shelf-life extension and food safety of meat and meat products. Use of antimicrobial substances can control the microbial population and target specific microorganisms to provide higher safety and quality products. Many classes of antimicrobial compounds have been evaluated in film structures, both synthetic polymers and edible films: organic acids and their salts, enzymes, bacteriocins, and miscellaneous compounds such as triclosan, silver zeolites, and fungicides. The characteristics of some antimicrobial packaging systems are reviewed in this article. The regulatory status of antimicrobial packaging in EU is also examined. PMID:22061613

  10. An alternative discourse of productive aging: A self-restrained approach in older Chinese people in Hong Kong.

    PubMed

    Luo, Minxia; Chui, Ernest Wing-Tak

    2016-08-01

    While Western discourses regarding productive aging emphasize individuals' contributions to economic productivity, the Confucian cultural heritage of the Chinese community may provide an alternative perspective. This qualitative study explores interpretations of what constitutes productive aging, based on a series of in-depth interviews with older Chinese people in Hong Kong. It shows that some of these individuals adopted a passive and indirect interpretation of productive aging, distinct from that found in Western countries. The Confucianism-based, collectivist, normative order underpinning Hong Kong society disposed these older people to adopting a self-restrained attitude with the aim of avoiding becoming a burden to others, especially family members. Such a tendency toward self-restraint or avoidance also encompassed a compromise between ideals and reality, with the older people opting to compromise their expectations of the younger generation as a whole, their adult children in particular, in terms of respect and reciprocity. PMID:27531450

  11. Capacitive Sensing for Non-Invasive Breathing and Heart Monitoring in Non-Restrained, Non-Sedated Laboratory Mice

    PubMed Central

    González-Sánchez, Carlos; Fraile, Juan-Carlos; Pérez-Turiel, Javier; Damm, Ellen; Schneider, Jochen G.; Zimmermann, Heiko; Schmitt, Daniel; Ihmig, Frank R.

    2016-01-01

    Animal testing plays a vital role in biomedical research. Stress reduction is important for improving research results and increasing the welfare and the quality of life of laboratory animals. To estimate stress we believe it is of great importance to develop non-invasive techniques for monitoring physiological signals during the transport of laboratory animals, thereby allowing the gathering of information on the transport conditions, and, eventually, the improvement of these conditions. Here, we study the suitability of commercially available electric potential integrated circuit (EPIC) sensors, using both contact and contactless techniques, for monitoring the heart rate and breathing rate of non-restrained, non-sedated laboratory mice. The design has been tested under different scenarios with the aim of checking the plausibility of performing contactless capture of mouse heart activity (ideally with an electrocardiogram). First experimental results are shown. PMID:27399713

  12. Restrained and External-Emotional Eating Patterns in Young Overweight Children–Results of the Ulm Birth Cohort Study

    PubMed Central

    Brandt, Stephanie; Moss, Anja; Weck, Melanie; Florath, Ines; Wabitsch, Martin; Hebebrand, Johannes; Schimmelmann, Benno G.; Christiansen, Hanna

    2014-01-01

    Childhood obesity is one of the greatest public health challenges in Western countries. Abnormal eating behavior is thought to be a developmental trajectory to obesity. The Eating Pattern Inventory for Children (EPI-C) has not been used for children as young as eight years, and possible associations with body weight have not yet been established. Five hundred and twenty-one children of the Ulm Birth Cohort Study (UBCS; age eight) filled out the EPI-C and BMI was assessed. Adequacy of the scales was tested with confirmatory factor analysis and a MANOVA and cluster analysis established associations between eating patterns and BMI. The factor structure of the EPI-C was confirmed (GFI = .968) and abnormal eating behavior was associated with overweight (χ2(8) = 79.29, p<.001). The EPI-C is a valid assessment tool in this young age group. Overweight children consciously restrain their eating. PMID:25141134

  13. Solution structures of psoralen monoadducted and cross-linked DNA oligomers by NMR spectroscopy and restrained molecular dynamics

    SciTech Connect

    Spielmann, H.P.; Dwyer, T.J.; Hearst, J.E. |

    1995-10-10

    We have used two-dimensional {sup 1}H NMR spectroscopy to determine the solution structures of the 4,5{prime}, 8-trimethylpsoralen (HMT) furanside monoadducted (MAf) and the photoisomeric HMT interstrand cross-linked (XL) DNA oligonucleotide d(t{prime}-GCGTACGC-3{prime}){sub 2}. The determination of the structure was based on total relaxation matrix analysis of the NOESY cross-peak intensities using the program MARDIGRAS. Improved procedures to consider the experimental {open_quotes}noise{close_quotes} in NOESY spectra during these calculations have been employed. The NOE-derived distance restraints were applied in restrained molecular dynamics calculations. Twenty final structures each were generated for both the MAf and XL from both A-form and B-form dsDNA starting structures. 80 refs., 7 figs., 6 tabs.

  14. Capacitive Sensing for Non-Invasive Breathing and Heart Monitoring in Non-Restrained, Non-Sedated Laboratory Mice.

    PubMed

    González-Sánchez, Carlos; Fraile, Juan-Carlos; Pérez-Turiel, Javier; Damm, Ellen; Schneider, Jochen G; Zimmermann, Heiko; Schmitt, Daniel; Ihmig, Frank R

    2016-01-01

    Animal testing plays a vital role in biomedical research. Stress reduction is important for improving research results and increasing the welfare and the quality of life of laboratory animals. To estimate stress we believe it is of great importance to develop non-invasive techniques for monitoring physiological signals during the transport of laboratory animals, thereby allowing the gathering of information on the transport conditions, and, eventually, the improvement of these conditions. Here, we study the suitability of commercially available electric potential integrated circuit (EPIC) sensors, using both contact and contactless techniques, for monitoring the heart rate and breathing rate of non-restrained, non-sedated laboratory mice. The design has been tested under different scenarios with the aim of checking the plausibility of performing contactless capture of mouse heart activity (ideally with an electrocardiogram). First experimental results are shown. PMID:27399713

  15. Molecular Detection of Antimicrobial Resistance

    PubMed Central

    Fluit, Ad C.; Visser, Maarten R.; Schmitz, Franz-Josef

    2001-01-01

    The determination of antimicrobial susceptibility of a clinical isolate, especially with increasing resistance, is often crucial for the optimal antimicrobial therapy of infected patients. Nucleic acid-based assays for the detection of resistance may offer advantages over phenotypic assays. Examples are the detection of the methicillin resistance-encoding mecA gene in staphylococci, rifampin resistance in Mycobacterium tuberculosis, and the spread of resistance determinants across the globe. However, molecular assays for the detection of resistance have a number of limitations. New resistance mechanisms may be missed, and in some cases the number of different genes makes generating an assay too costly to compete with phenotypic assays. In addition, proper quality control for molecular assays poses a problem for many laboratories, and this results in questionable results at best. The development of new molecular techniques, e.g., PCR using molecular beacons and DNA chips, expands the possibilities for monitoring resistance. Although molecular techniques for the detection of antimicrobial resistance clearly are winning a place in routine diagnostics, phenotypic assays are still the method of choice for most resistance determinations. In this review, we describe the applications of molecular techniques for the detection of antimicrobial resistance and the current state of the art. PMID:11585788

  16. Helical Antimicrobial Sulfono- {gamma} -AApeptides

    SciTech Connect

    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.

  17. Antimicrobial resistance: a global response.

    PubMed Central

    Smith, Richard D.; Coast, Joanna

    2002-01-01

    Resistance to antimicrobial therapies reduces the effectiveness of these drugs, leading to increased morbidity, mortality, and health care expenditure. Because globalization increases the vulnerability of any country to diseases occurring in other countries, resistance presents a major threat to global public health, and no country acting on its own can adequately protect the health of its population against it. International collective action is therefore essential. Nevertheless, responsibility for health remains predominantly national. Consequently, there is a potentially significant disparity between the problems and solutions related to antimicrobial resistance and the institutions and mechanisms that are available to deal with them. This paper considers the capacity of national and international institutions and mechanisms to generate a collective response to antimicrobial resistance. Strategies for containing resistance are outlined, with particular reference to globally coordinated activities of countries. The adequacy of national and international responses to resistance is assessed, and the actions that international bodies could take to solve difficulties associated with present responses are highlighted. Approaches are suggested for securing international collective action for the containment of antimicrobial resistance. PMID:11953791

  18. ANTIMICROBIAL EFFECT OF INTRACANAL SUBSTANCES

    PubMed Central

    Carreira, Cláudia de Moura; dos Santos, Silvana Soléo Ferreira; Jorge, Antônio Olavo Cardoso; Lage-Marques, José Luiz

    2007-01-01

    In some situations, endodontic infections do not respond to therapeutic protocol. In these cases, it is suggested the administration of an alternative intracanal medication that presents a wide spectrum of action and has an in-depth effect on the root canal system. The purpose of this study was to assess the antimicrobial action of ciprofloxacin, metronidazole and polyethylene glycol and natrosol vehicles with different associations and concentrations. The minimum inhibitory concentration (MIC) was determined by using the agar dilution method. The culture media (Müller-Hinton agar) were prepared containing antimicrobial agents at multiple two-fold dilutions of 0.25 to 16 µg/mL, and with the vehicles at the concentrations of 50, 45, 40, 35, 30 and 25%. Twenty-three microbial strains were selected for the study. Metronidazole was not capable of eliminating any of the tested microorganisms. The association of ciprofloxacin with metronidazole resulted in a reduction of the MIC. The vehicle polyethylene glycol inhibited the growth of 100% of the tested strains, while natrosol inhibited 18% of the strains. Ciprofloxacin formulations with polyethylene glycol presented better effects than those of formulations to which metronidazole was added. It was possible to conclude that ciprofloxacin presented antimicrobial action against all tested bacterial strains, and its association with metronidazole was synergic. The vehicle polyethylene glycol showed antimicrobial effect and the ciprofloxacin/polyethylene glycol association was the most effective combination for reducing the tested bacteria and yeasts. PMID:19089178

  19. ANTIMICROBIAL RESISTANCE TRENDS IN SALMONELLA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Since the early 1990’s there has been increasing awareness and concern regarding the development of antimicrobial resistance among bacteria of public health significance. Reports targeting zoonotic bacteria, and in particular Salmonella species, suggest that resistance is trending upwar...

  20. Antimicrobial activity of Securidaca longipedunculata.

    PubMed

    Ajali, U; Chukwurah, B K C

    2004-11-01

    The folk herbal uses of Securidaca longipedunculata in the treatment of diarrhea, boils, gonorrhea, and cough prompted phytochemical analyses and antimicrobial activity screening of extracts of the root. Some flavonoids isolated showed activity against many micro-organisms. These flavonoids were isolated using chromatographic methods. PMID:15636189

  1. Antimicrobial Polymers with Metal Nanoparticles

    PubMed Central

    Palza, Humberto

    2015-01-01

    Metals, such as copper and silver, can be extremely toxic to bacteria at exceptionally low concentrations. Because of this biocidal activity, metals have been widely used as antimicrobial agents in a multitude of applications related with agriculture, healthcare, and the industry in general. Unlike other antimicrobial agents, metals are stable under conditions currently found in the industry allowing their use as additives. Today these metal based additives are found as: particles, ions absorbed/exchanged in different carriers, salts, hybrid structures, etc. One recent route to further extend the antimicrobial applications of these metals is by their incorporation as nanoparticles into polymer matrices. These polymer/metal nanocomposites can be prepared by several routes such as in situ synthesis of the nanoparticle within a hydrogel or direct addition of the metal nanofiller into a thermoplastic matrix. The objective of the present review is to show examples of polymer/metal composites designed to have antimicrobial activities, with a special focus on copper and silver metal nanoparticles and their mechanisms. PMID:25607734

  2. Antimicrobial activity of resveratrol analogues.

    PubMed

    Chalal, Malik; Klinguer, Agnès; Echairi, Abdelwahad; Meunier, Philippe; Vervandier-Fasseur, Dominique; Adrian, Marielle

    2014-01-01

    Stilbenes, especially resveratrol and its derivatives, have become famous for their positive effects on a wide range of medical disorders, as indicated by a huge number of published studies. A less investigated area of research is their antimicrobial properties. A series of 13 trans-resveratrol analogues was synthesized via Wittig or Heck reactions, and their antimicrobial activity assessed on two different grapevine pathogens responsible for severe diseases in the vineyard. The entire series, together with resveratrol, was first evaluated on the zoospore mobility and sporulation level of Plasmopara viticola (the oomycete responsible for downy mildew). Stilbenes displayed a spectrum of activity ranging from low to high. Six of them, including the most active ones, were subsequently tested on the development of Botrytis cinerea (fungus responsible for grey mold). The results obtained allowed us to identify the most active stilbenes against both grapevine pathogens, to compare the antimicrobial activity of the evaluated series of stilbenes, and to discuss the relationship between their chemical structure (number and position of methoxy and hydroxy groups) and antimicrobial activity. PMID:24918540

  3. Investigational antimicrobial agents of 2013.

    PubMed

    Pucci, Michael J; Bush, Karen

    2013-10-01

    New antimicrobial agents are always needed to counteract the resistant pathogens that continue to be selected by current therapeutic regimens. This review provides a survey of known antimicrobial agents that were currently in clinical development in the fall of 2012 and spring of 2013. Data were collected from published literature primarily from 2010 to 2012, meeting abstracts (2011 to 2012), government websites, and company websites when appropriate. Compared to what was reported in previous surveys, a surprising number of new agents are currently in company pipelines, particularly in phase 3 clinical development. Familiar antibacterial classes of the quinolones, tetracyclines, oxazolidinones, glycopeptides, and cephalosporins are represented by entities with enhanced antimicrobial or pharmacological properties. More importantly, compounds of novel chemical structures targeting bacterial pathways not previously exploited are under development. Some of the most promising compounds include novel β-lactamase inhibitor combinations that target many multidrug-resistant Gram-negative bacteria, a critical medical need. Although new antimicrobial agents will continue to be needed to address increasing antibiotic resistance, there are novel agents in development to tackle at least some of the more worrisome pathogens in the current nosocomial setting. PMID:24092856

  4. Investigational Antimicrobial Agents of 2013

    PubMed Central

    Pucci, Michael J.

    2013-01-01

    SUMMARY New antimicrobial agents are always needed to counteract the resistant pathogens that continue to be selected by current therapeutic regimens. This review provides a survey of known antimicrobial agents that were currently in clinical development in the fall of 2012 and spring of 2013. Data were collected from published literature primarily from 2010 to 2012, meeting abstracts (2011 to 2012), government websites, and company websites when appropriate. Compared to what was reported in previous surveys, a surprising number of new agents are currently in company pipelines, particularly in phase 3 clinical development. Familiar antibacterial classes of the quinolones, tetracyclines, oxazolidinones, glycopeptides, and cephalosporins are represented by entities with enhanced antimicrobial or pharmacological properties. More importantly, compounds of novel chemical structures targeting bacterial pathways not previously exploited are under development. Some of the most promising compounds include novel β-lactamase inhibitor combinations that target many multidrug-resistant Gram-negative bacteria, a critical medical need. Although new antimicrobial agents will continue to be needed to address increasing antibiotic resistance, there are novel agents in development to tackle at least some of the more worrisome pathogens in the current nosocomial setting. PMID:24092856

  5. Access to effective antimicrobials: a worldwide challenge.

    PubMed

    Laxminarayan, Ramanan; Matsoso, Precious; Pant, Suraj; Brower, Charles; Røttingen, John-Arne; Klugman, Keith; Davies, Sally

    2016-01-01

    Recent years have seen substantial improvements in life expectancy and access to antimicrobials, especially in low-income and lower-middle-income countries, but increasing pathogen resistance to antimicrobials threatens to roll back this progress. Resistant organisms in health-care and community settings pose a threat to survival rates from serious infections, including neonatal sepsis and health-care-associated infections, and limit the potential health benefits from surgeries, transplants, and cancer treatment. The challenge of simultaneously expanding appropriate access to antimicrobials, while restricting inappropriate access, particularly to expensive, newer generation antimicrobials, is unique in global health and requires new approaches to financing and delivering health care and a one-health perspective on the connections between pathogen transmission in animals and humans. Here, we describe the importance of effective antimicrobials. We assess the disease burden caused by limited access to antimicrobials, attributable to resistance to antimicrobials, and the potential effect of vaccines in restricting the need for antibiotics. PMID:26603918

  6. Complex fault interactions in a restraining bend on the San Andreas fault, southern Santa Cruz Mountains, California

    SciTech Connect

    Schwartz, S.Y.; Orange, D.L.; Anderson, R.S. )

    1990-07-01

    The unusual oblique thrust mechanism of the October 18, 1989 Loma Prieta earthquake focused attention on the complex tectonic setting of this segment of the San Andreas Fault. Near the mainshock epicenter, the San Andreas Fault curves to the left defining a restraining bend. The large thrust component of the mainshock focal mechanism is consistent with the horizontal compression expected across restraining bends. However, repeated Loma Prieta type earthquakes cannot exclusively produce the observed topography of the southern Santa Cruz Mountains, the highest point of which experienced subsidence during the 1989 earthquake. In this paper, the authors integrate seismic, geomorphic and tectonic data to investigate the possibility that motions on faults adjacent to the San Andreas Fault play an important role in producing the observed topography. The three-dimensional geometry of active faults in this region is imaged using the Loma Prieta preshock and aftershock sequences. The most conspicuous features of the fault geometries at depth are: (1) the presence of two distinct zones of seismicity corresponding to the San Andreas and the Sargent-Berrocal Fault Zones, (2) the concave upward shape of the Loma Prieta rupture surface, (3) the reduction in dip of the deepest portions of the rupture plane as the mainshock hypocenter is approached, (4) the apparent transfer of shallow slip in some areas from faults in the San Andreas Fault Zone to those in the Sargent-Berrocal Fault Zone, and (5) the presence of a deep northeasterly dipping plane associated with the Sargent-Berrocal Fault Zone. The authors find that a model of fault interactions which involves displacement on faults in both the San Andreas and the Sargent-Berrocal Fault Zones is consistent with Loma Prieta coseismic displacements, preshock and aftershock seismicity and observed topography.

  7. Endotoxin reduces muscle protein synthesis and restrains translation initiation by decreasing eIF4G phosphorylation in neonatal and young pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Endotoxin (LPS) reduces muscle protein synthesis by restraining translation in the presence of fed levels of insulin and amino acids. "In vivo" effects of LPS on translation initiation in muscle during basal fasting insulin and amino acid conditions have not been determined in neonates, whose muscle...

  8. Antimicrobial Stewardship and Urinary Tract Infections

    PubMed Central

    Abbo, Lilian M.; Hooton, Thomas M.

    2014-01-01

    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. PMID:27025743

  9. An evaluation of the association between an antimicrobial stewardship score and antimicrobial usage

    PubMed Central

    Pakyz, Amy L.; Moczygemba, Leticia R.; Wang, Hui; Stevens, Michael P.; Edmond, Michael B.

    2015-01-01

    Objectives To determine whether an antimicrobial stewardship ‘intensity’ score predicts hospital antimicrobial usage. Methods An antimicrobial stewardship score for 44 academic medical centres was developed that comprised two main categories: resources (antimicrobial stewardship programme personnel and automated surveillance software) and strategies (preauthorization, audit with intervention and feedback, education, guidelines and clinical pathways, parenteral to oral therapy programmes, de-escalation of therapy, antimicrobial order forms and dose optimization). Multiple regression analyses were used to assess whether the composite score and also the categories were associated with either total or antimicrobial stewardship programme-target antimicrobial use as measured in days of therapy. Results The mean antimicrobial stewardship programme score was 55 (SD 21); the total composite score was not significantly associated with total or target antimicrobial use [estimate –0.49 (95% CI –2.30 to 0.89)], while the category strategies was significantly and negatively associated with target antimicrobial use [–5.91 (95% CI –9.51 to –2.31)]. Conclusions The strategy component of a score developed to measure the intensity of antimicrobial stewardship was associated with the amount of antimicrobials used. Thus, the number and types of strategies employed by antimicrobial stewardship programmes may be of particular importance in programme effectiveness. PMID:25614043

  10. Temporin-SHf, a New Type of Phe-rich and Hydrophobic Ultrashort Antimicrobial Peptide*

    PubMed Central

    Abbassi, Feten; Lequin, Olivier; Piesse, Christophe; Goasdoué, Nicole; Foulon, Thierry; Nicolas, Pierre; Ladram, Ali

    2010-01-01

    Because issues of cost and bioavailability have hampered the development of gene-encoded antimicrobial peptides to combat infectious diseases, short linear peptides with high microbial cell selectivity have been recently considered as antibiotic substitutes. A new type of short antimicrobial peptide, designated temporin-SHf, was isolated and cloned from the skin of the frog Pelophylax saharica. Temporin-SHf has a highly hydrophobic sequence (FFFLSRIFa) and possesses the highest percentage of Phe residues of any known peptide or protein. Moreover, it is the smallest natural linear antimicrobial peptide found to date, with only eight residues. Despite its small size and hydrophobicity, temporin-SHf has broad-spectrum microbicidal activity against Gram-positive and Gram-negative bacteria and yeasts, with no hemolytic activity. CD and NMR spectroscopy combined with restrained molecular dynamics calculations showed that the peptide adopts a well defined non-amphipathic α-helical structure from residue 3 to 8, when bound to zwitterionic dodecyl phosphocholine or anionic SDS micelles. Relaxation enhancement caused by paramagnetic probes showed that the peptide adopts nearly parallel orientations to the micelle surface and that the helical structure is stabilized by a compact hydrophobic core on one face that penetrates into the micelle interior. Differential scanning calorimetry on multilamellar vesicles combined with membrane permeabilization assays on bacterial cells indicated that temporin-SHf disrupts the acyl chain packing of anionic lipid bilayers, thereby triggering local cracks and microbial membrane disintegration through a detergent-like effect probably via the carpet mechanism. The short length, compositional simplicity, and broad-spectrum activity of temporin-SHf make it an attractive candidate to develop new antibiotic agents. PMID:20308076

  11. Antimicrobial Peptides from Marine Proteobacteria

    PubMed Central

    Desriac, Florie; Jégou, Camille; Balnois, Eric; Brillet, Benjamin; Le Chevalier, Patrick; Fleury, Yannick

    2013-01-01

    After years of inadequate use and the emergence of multidrug resistant (MDR) strains, the efficiency of “classical” antibiotics has decreased significantly. New drugs to fight MDR strains are urgently needed. Bacteria hold much promise as a source of unusual bioactive metabolites. However, the potential of marine bacteria, except for Actinomycetes and Cyanobacteria, has been largely underexplored. In the past two decades, the structures of several antimicrobial compounds have been elucidated in marine Proteobacteria. Of these compounds, polyketides (PKs), synthesised by condensation of malonyl-coenzyme A and/or acetyl-coenzyme A, and non-ribosomal peptides (NRPs), obtained through the linkage of (unusual) amino acids, have recently generated particular interest. NRPs are good examples of naturally modified peptides. Here, we review and compile the data on the antimicrobial peptides isolated from marine Proteobacteria, especially NRPs. PMID:24084784

  12. Antimicrobial metabolites from marine microorganisms.

    PubMed

    Habbu, Prasanna; Warad, Vijayanand; Shastri, Rajesh; Madagundi, Smita; Kulkarni, Venkatrao H

    2016-02-01

    Marine ecological niches have recently been described as "particularly promising" sources for search of new antimicrobials to combat antibiotic-resistant strains of pathogenic microorganisms. Marine organisms are excellent sources for many industrial products, but they are partly explored. Over 30 000 compounds have been isolated from marine sources. Bacteria, fungi, and cyanobacteria obtained from various marine sources secret several industrially useful bioactive compounds, possessing antibacterial, antifungal, and antimycobacterial activities. Sustainable cultivation methods for promising marine organisms and biotechnological processes for selected compounds can be developed, along with the establishment of biosensors for monitoring the target compounds. The semisynthetic modifications of marine-based bioactive compounds produce their new derivatives, structural analogs and mimetics that could serve as novel lead compounds against resistant pathogens. The present review focuses on promising antimicrobial compounds isolated from marine microbes from 1991-2013. PMID:26968676

  13. Bacteriophage endolysins as novel antimicrobials

    PubMed Central

    Schmelcher, Mathias; Donovan, David M; Loessner, Martin J

    2013-01-01

    Endolysins are enzymes used by bacteriophages at the end of their replication cycle to degrade the peptidoglycan of the bacterial host from within, resulting in cell lysis and release of progeny virions. Due to the absence of an outer membrane in the Gram-positive bacterial cell wall, endolysins can access the peptidoglycan and destroy these organisms when applied externally, making them interesting antimicrobial candidates, particularly in light of increasing bacterial drug resistance. This article reviews the modular structure of these enzymes, in which cell wall binding and catalytic functions are separated, as well as their mechanism of action, lytic activity and potential as antimicrobials. It particularly focuses on molecular engineering as a means of optimizing endolysins for specific applications, highlights new developments that may render these proteins active against Gram-negative and intracellular pathogens and summarizes the most recent applications of endolysins in the fields of medicine, food safety, agriculture and biotechnology. PMID:23030422

  14. Antimicrobial Activity of Commercial Nanoparticles

    NASA Astrophysics Data System (ADS)

    Gajjar, Priyanka; Pettee, Brian; Britt, David W.; Huang, Wenjie; Johnson, William P.; Anderson, Anne J.

    2009-07-01

    Engineered nanoparticles are finding increased use in applications ranging from biosensors to prophylactic antimicrobials embedded in socks. The release of heavy metal-containing nanoparticles (NP) into the environment may be harmful to the efficacy of beneficial microbes that function in element cycling, pollutant degradation, and plant growth. Antimicrobial activity of commercial NP of Ag, CuO, and ZnO is demonstrated here against the beneficial soil microbe, Pseudomonas putida KT2440, which was modified to serve as a bioluminescent sentinel organism. "As manufactured" preparations of nano- Ag, -CuO, and -ZnO caused rapid, dose dependent loss of light output in the biosensor. Bulk equivalents of these products showed no inhibitory activity, indicating that particle size was determinant in activity.

  15. [Biofilms, tolerance and antimicrobial resistance].

    PubMed

    Bahar, Gül

    2002-01-01

    Virtually every surface examined in natural, industrial and pathogenic ecosystems are colonized by biofilms consisting of adherent populations of microorganisms surrounded with a glycocalyx matrix. The development of biofilms has important economic and medical consequences. The development and use of a broad range of medical devices made us recognize a variety of infections caused by microorganisms that were regarded previously as harmless. Infections caused by biofilms are difficult to eradicate with antimicrobial treatment, and in-vitro susceptibility tests show significant resistance of biofilm cells to be killed. Advances in our understanding of biofilm formation can assist in the development of novel strategies for the prevention and treatment of infections caused by biofilms. In this review article, structures, general properties and antimicrobial resistance mechanisms of biofilms were discussed under the light of recent literature. PMID:12838670

  16. Cholic acid derivatives: novel antimicrobials.

    PubMed

    Savage, P B; Li, C

    2000-02-01

    Mimics of squalamine and polymyxin B (PMB) have been prepared from cholic acid in hope of finding new antimicrobial agents. The squalamine mimics include the polyamine and sulphate functionalities found in the parent antibiotic, however, the positions relative to the steroid nucleus have been exchanged. The PMB mimics include the conservation of functionality among the polymyxin family of antibiotics, the primary amine groups and a hydrophobic chain. Although the squalamine and PMB mimics are morphologically dissimilar, they display similar activities. Both are simple to prepare and demonstrate broad spectrum antimicrobial activity against Gram-negative and Gram-positive organisms. Specific examples may be inactive alone, yet effectively permeabilise the outer membranes of Gram-negative bacteria rendering them sensitive to hydrophobic antibiotics. Problems associated with some of the squalamine and PMB mimics stem from their haemolytic activity and interactions with serum proteins, however, examples exist without these side effects which can sensitise Gram-negative bacteria to hydrophobic antibiotics. PMID:11060676

  17. Antimicrobials & cholera: are we stranded?

    PubMed

    Ghosh, Amit; Ramamurthy, T

    2011-02-01

    Antimicrobial resistance poses a major threat in the treatment of infectious diseases. Though significant progress in the management of diarrhoeal diseases has been achieved by improved hygiene, development of new antimicrobials and vaccines, the burden remains the same, especially in children below 5 yr of age. In the case of cholera, though oral rehydration treatment is the mainstay, antimicrobial therapy is mandatory at times to reduce the volume of stool and shorten the duration of the disease. Though for many pathogens, antimicrobial resistance emerged soon after the introduction of antibiotics, Vibrio cholerae remained sensitive to most of the antibiotics for quite a long period. However, the scenario changed over the years and today, V. cholerae strains isolated world over are resistant to multiple antibiotics. A myriad number of mechanisms underlie this phenomenon. These include production of extended-spectrum beta-lactamases, enhanced multi-drug efflux pump activity, plasmid-mediated quinolone and fluoroquinolone resistance, and chromosomal mutations. Horizontal transfer of resistance determinants with mobile genetic elements like integrons and the integrating conjugative elements (ICEs), SXTs help in the dissemination of drug resistance. Though all strains isolated are not resistant to all antibiotics and we are not as yet "stranded", expanding spectrum of drug resistance is a definite cause for concern. Pipelines of discovery of new antibiotics are drying up as major pharmaceutical companies are losing interest in investing money in this endeavour, mainly due to the short shelf-life of the antibiotics and also due to the fast emergence of drug resistance. To address this issue, attempts are now being made to discover drugs which are pathogen specific and target their "virulence mechanisms". It is expected that development of resistance against such antibiotics would take much longer. This review briefly focuses on all these issues. PMID:21415499

  18. Plant Products as Antimicrobial Agents

    PubMed Central

    Cowan, Marjorie Murphy

    1999-01-01

    The use of and search for drugs and dietary supplements derived from plants have accelerated in recent years. Ethnopharmacologists, botanists, microbiologists, and natural-products chemists are combing the Earth for phytochemicals and “leads” which could be developed for treatment of infectious diseases. While 25 to 50% of current pharmaceuticals are derived from plants, none are used as antimicrobials. Traditional healers have long used plants to prevent or cure infectious conditions; Western medicine is trying to duplicate their successes. Plants are rich in a wide variety of secondary metabolites, such as tannins, terpenoids, alkaloids, and flavonoids, which have been found in vitro to have antimicrobial properties. This review attempts to summarize the current status of botanical screening efforts, as well as in vivo studies of their effectiveness and toxicity. The structure and antimicrobial properties of phytochemicals are also addressed. Since many of these compounds are currently available as unregulated botanical preparations and their use by the public is increasing rapidly, clinicians need to consider the consequences of patients self-medicating with these preparations. PMID:10515903

  19. Collagen-like antimicrobial peptides.

    PubMed

    Masuda, Ryo; Kudo, Masakazu; Dazai, Yui; Mima, Takehiko; Koide, Takaki

    2016-11-01

    Combinatorial library composed of rigid rod-like peptides with a triple-helical scaffold was constructed. The component peptides were designed to have various combinations of basic and neutral (or hydrophobic) amino acid residues based on collagen-like (Gly-Pro-Yaa)-repeating sequences, inspired from the basic and amphiphilic nature of naturally occurring antimicrobial peptides. Screening of the peptide pools resulted in identification of antimicrobial peptides. A structure-activity relationship study revealed that the position of Arg-cluster at N-terminus and cystine knots at C-terminus in the triple helix significantly contributed to the antimicrobial activity. The most potent peptide RO-A showed activity against Gram-negative Escherichia coli and Gram-positive Bacillus subtilis. In addition, Escherichia coli exposed to RO-A resulted in abnormal elongation of the cells. RO-A was also shown to have remarkable stability in human serum and low cytotoxicity to mammalian cells. © 2016 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 453-459, 2016. PMID:27271210

  20. Antimicrobial Properties of Amyloid Peptides

    PubMed Central

    Kagan, Bruce L.; Jang, Hyunbum; Capone, Ricardo; Arce, Fernando Teran; Ramachandran, Srinivasan; Lal, Ratnesh; Nussinov, Ruth

    2011-01-01

    More than two dozen clinical syndromes known as amyloid diseases are characterized by the buildup of extended insoluble fibrillar deposits in tissues. These amorphous Congo red staining deposits known as amyloids exhibit a characteristic green birefringence and cross-β structure. Substantial evidence implicates oligomeric intermediates of amyloids as toxic species in the pathogenesis of these chronic disease states. A growing body of data has suggested that these toxic species form ion channels in cellular membranes causing disruption of calcium homeostasis, membrane depolarization, energy drainage, and in some cases apoptosis. Amyloid peptide channels exhibit a number of common biological properties including the universal U-shape β-strand-turn-β-strand structure, irreversible and spontaneous insertion into membranes, production of large heterogeneous single-channel conductances, relatively poor ion selectivity, inhibition by Congo red, and channel blockade by zinc. Recent evidence has suggested that increased amounts of amyloids are not only toxic to its host target cells but also possess antimicrobial activity. Furthermore, at least one human antimicrobial peptide, protegrin-1, which kills microbes by a channel-forming mechanism, has been shown to possess the ability to form extended amyloid fibrils very similar to those of classic disease-forming amyloids. In this paper, we will review the reported antimicrobial properties of amyloids and the implications of these discoveries for our understanding of amyloid structure and function. PMID:22081976

  1. Antimicrobial proteins of murine macrophages.

    PubMed Central

    Hiemstra, P S; Eisenhauer, P B; Harwig, S S; van den Barselaar, M T; van Furth, R; Lehrer, R I

    1993-01-01

    Three murine microbicidal proteins (MUMPs) were purified from cells of the murine macrophage cell line RAW264.7 that had been activated by gamma interferon. Similar proteins were also present in nonactivated RAW264.7 cells, in cells of the murine macrophage cell line J774A.1, and in resident and activated murine peritoneal macrophages. MUMP-1, MUMP-2, and MUMP-3 killed Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, Mycobacterium fortuitum, and Cryptococcus neoformans in vitro. MUMP-1 resembled an H1 histone but was unusual because its N-terminal residue (serine) was not N acetylated. Although MUMP-2 was N terminally blocked, its high lysine/arginine ratio and its reactivity with an antibody to H1 histones suggested that it also belonged to the H1 histone family. MUMP-3 was identical to histone H2B in 30 of 30 amino-terminal residues. Although the antimicrobial properties of histones have been recognized for decades, this is the first evidence that such proteins may endow the lysosomal apparatus of macrophages with nonoxidative antimicrobial potential. Other MUMPs, including some with a more restricted antimicrobial spectrum and one that appeared to be induced in RAW264.7 cells after gamma interferon stimulation, were noted but remain to be characterized. Images PMID:8514411

  2. Antimicrobial technology in orthopedic and spinal implants.

    PubMed

    Eltorai, Adam Em; Haglin, Jack; Perera, Sudheesha; Brea, Bielinsky A; Ruttiman, Roy; Garcia, Dioscaris R; Born, Christopher T; Daniels, Alan H

    2016-06-18

    Infections can hinder orthopedic implant function and retention. Current implant-based antimicrobial strategies largely utilize coating-based approaches in order to reduce biofilm formation and bacterial adhesion. Several emerging antimicrobial technologies that integrate a multidisciplinary combination of drug delivery systems, material science, immunology, and polymer chemistry are in development and early clinical use. This review outlines orthopedic implant antimicrobial technology, its current applications and supporting evidence, and clinically promising future directions. PMID:27335811

  3. Antimicrobial polymer films for food packaging

    NASA Astrophysics Data System (ADS)

    Concilio, S.; Piotto, S.; Sessa, L.; Iannelli, P.; Porta, A.; Calabrese, E. C.; Galdi, M. R.; Incarnato, L.

    2012-07-01

    New antimicrobial polymeric systems were realized introducing new antimicrobial azo compounds in PP and LDPE matrices. The polymeric materials containing different percentage of azo compounds were mold-casted and the obtained film were tested in vitro against Gram+ and Gram- bacteria and fungi. These results hold promise for the fabrication of bacteria-resistant polymer films by means of simple melt processing with antimicrobial azo-dyes.

  4. Correlations between Income Inequality and Antimicrobial Resistance

    PubMed Central

    Kirby, Andrew; Herbert, Annie

    2013-01-01

    Objectives The aim of this study is to investigate if correlations exist between income inequality and antimicrobial resistance. This study’s hypothesis is that income inequality at the national level is positively correlated with antimicrobial resistance within developed countries. Data collection and analysis Income inequality data were obtained from the Standardized World Income Inequality Database. Antimicrobial resistance data were obtained from the European antimicrobial Resistance Surveillance Network and outpatient antimicrobial consumption data, measured by Defined daily Doses per 1000 inhabitants per day, from the European Surveillance of antimicrobial Consumption group. Spearman’s correlation coefficient (r) defined strengths of correlations of: > 0.8 as strong, > 0.5 as moderate and > 0.2 as weak. Confidence intervals and p values were defined for all r values. Correlations were calculated for the time period 2003-10, for 15 European countries. Results Income inequality and antimicrobial resistance correlations which were moderate or strong, with 95% confidence intervals > 0, included the following. Enterococcus faecalis resistance to aminopenicillins, vancomycin and high level gentamicin was moderately associated with income inequality (r= ≥0.54 for all three antimicrobials). Escherichia coli resistance to aminoglycosides, aminopenicillins, third generation cephalosporins and fluoroquinolones was moderately-strongly associated with income inequality (r= ≥0.7 for all four antimicrobials). Klebsiella pneumoniae resistance to third generation cephalosporins, aminoglycosides and fluoroquinolones was moderately associated with income inequality (r= ≥0.5 for all three antimicrobials). Staphylococcus aureus methicillin resistance and income inequality were strongly associated (r=0.87). Conclusion As income inequality increases in European countries so do the rates of antimicrobial resistance for bacteria including E. faecalis, E. coli, K. pneumoniae

  5. Antimicrobial technology in orthopedic and spinal implants

    PubMed Central

    Eltorai, Adam EM; Haglin, Jack; Perera, Sudheesha; Brea, Bielinsky A; Ruttiman, Roy; Garcia, Dioscaris R; Born, Christopher T; Daniels, Alan H

    2016-01-01

    Infections can hinder orthopedic implant function and retention. Current implant-based antimicrobial strategies largely utilize coating-based approaches in order to reduce biofilm formation and bacterial adhesion. Several emerging antimicrobial technologies that integrate a multidisciplinary combination of drug delivery systems, material science, immunology, and polymer chemistry are in development and early clinical use. This review outlines orthopedic implant antimicrobial technology, its current applications and supporting evidence, and clinically promising future directions. PMID:27335811

  6. Antimicrobial considerations in the perioperative patient.

    PubMed

    Boothe, Dawn Merton; Boothe, Harry W

    2015-05-01

    Surgical site infections are among the complications that can be reduced with the timely implementation of appropriate antimicrobial therapy. A 3-D approach to judicious antimicrobial use focuses on the de-escalation of systemic antimicrobial therapy, design of dosing regimens, and decontamination of the surgeon, patient, and environment. De-escalation can be accomplished in part through proper antimicrobial prophylaxis. Dosing regimens should be designed to maximize efficacy and minimize resistance. Decontamination includes disinfection of inanimate surfaces and timely application of appropriate antiseptics at concentrations that maximize efficacy. PMID:25758849

  7. The Potential of Antimicrobial Peptides as Biocides

    PubMed Central

    Laverty, Garry; Gorman, Sean P.; Gilmore, Brendan F.

    2011-01-01

    Antimicrobial peptides constitute a diverse class of naturally occurring antimicrobial molecules which have activity against a wide range of pathogenic microorganisms. Antimicrobial peptides are exciting leads in the development of novel biocidal agents at a time when classical antibiotics are under intense pressure from emerging resistance, and the global industry in antibiotic research and development stagnates. This review will examine the potential of antimicrobial peptides, both natural and synthetic, as novel biocidal agents in the battle against multi-drug resistant pathogen infections. PMID:22072905

  8. Antimicrobial Resistance: Is the World UNprepared?

    PubMed

    2016-09-01

    Long Blurb: On September 21st 2016 the United Nations General Assembly convenes in New York, United States to tackle a looming and seemingly inevitable global challenge with the potential to threaten the health and wellbeing of all people: antimicrobial resistance. In an Editorial, the PLOS Medicine Editors reflect on the challenge of coordinating the response to antimicrobial resistance in order to ensure the viability of current antimicrobials and the development of new therapies against resistant pathogens. Short Blurb: In this month's Editorial, the PLOS Medicine Editors reflect on the upcoming United Nations General Assembly meeting which convenes to discuss the global challenge of antimicrobial resistance. PMID:27618631

  9. Antimicrobial drugs for treating cholera

    PubMed Central

    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

  10. Excitatory amino acid transporters tonically restrain nTS synaptic and neuronal activity to modulate cardiorespiratory function.

    PubMed

    Matott, Michael P; Ruyle, Brian C; Hasser, Eileen M; Kline, David D

    2016-03-01

    The nucleus tractus solitarii (nTS) is the initial central termination site for visceral afferents and is important for modulation and integration of multiple reflexes including cardiorespiratory reflexes. Glutamate is the primary excitatory neurotransmitter in the nTS and is removed from the extracellular milieu by excitatory amino acid transporters (EAATs). The goal of this study was to elucidate the role of EAATs in the nTS on basal synaptic and neuronal function and cardiorespiratory regulation. The majority of glutamate clearance in the central nervous system is believed to be mediated by astrocytic EAAT 1 and 2. We confirmed the presence of EAAT 1 and 2 within the nTS and their colocalization with astrocytic markers. EAAT blockade withdl-threo-β-benzyloxyaspartic acid (TBOA) produced a concentration-related depolarization, increased spontaneous excitatory postsynaptic current (EPSC) frequency, and enhanced action potential discharge in nTS neurons. Solitary tract-evoked EPSCs were significantly reduced by EAAT blockade. Microinjection of TBOA into the nTS of anesthetized rats induced apneic, sympathoinhibitory, depressor, and bradycardic responses. These effects mimicked the response to microinjection of exogenous glutamate, and glutamate responses were enhanced by EAAT blockade. Together these data indicate that EAATs tonically restrain nTS excitability to modulate cardiorespiratory function. PMID:26719090

  11. The contribution of nasal receptors to the cardiac response to diving in restrained and unrestrained redhead ducks (Aythya americana).

    PubMed

    Furilla, R A; Jones, D R

    1986-03-01

    In restrained redhead ducks, forced submergence caused heart rate to fall from 100 +/- 3 beats min-1 (mean +/- S.E.M., N = 12) to a stable underwater rate of 35 +/- 4 beats min-1 (N = 12) within 5 s after submergence. Bradycardia was unaffected by breathing oxygen before a dive, but was virtually eliminated by local anaesthesia of the narial region. In contrast, in a dabbling duck (Anas platyrhynchos) bradycardia in short dives was eliminated by breathing oxygen before a dive. In unrestrained diving, on a man-made pond, heart rate in redheads diving voluntarily (y) was related to pre-dive heart rate (x) by the equation y = 76 + 0.29 +/- 0.05x +/- 17 (r2 = 0.71). Chasing, to induce submergence, had variable effects on this relationship. Local anaesthesia of the narial region inhibited voluntary diving but heart rates in chase-induced dives after nasal blockade were significantly higher, by 10-30%, than those obtained from untreated ducks in chase-induced dives. Breathing oxygen before voluntary dives had no apparent effect on heart rate after 2-5 s submergence. Voluntary head submersion by dabbling ducks caused no change in heart rate. We conclude that nasal receptors make only a minor contribution to cardiac responses in unrestrained dives, compared with forced dives, in diving ducks. Furthermore, these results show that little can be learned about cardiac responses in free diving ducks from studies of forced dives in dabblers or divers. PMID:3958677

  12. Thrombospondin-1 restrains neutrophil granule serine protease function and regulates the innate immune response during Klebsiella pneumoniae infection.

    PubMed

    Zhao, Y; Olonisakin, T F; Xiong, Z; Hulver, M; Sayeed, S; Yu, M T; Gregory, A D; Kochman, E J; Chen, B B; Mallampalli, R K; Sun, M; Silverstein, R L; Stolz, D B; Shapiro, S D; Ray, A; Ray, P; Lee, J S

    2015-07-01

    Neutrophil elastase (NE) and cathepsin G (CG) contribute to intracellular microbial killing but, if left unchecked and released extracellularly, promote tissue damage. Conversely, mechanisms that constrain neutrophil serine protease activity protect against tissue damage but may have the untoward effect of disabling the microbial killing arsenal. The host elaborates thrombospondin-1 (TSP-1), a matricellular protein released during inflammation, but its role during neutrophil activation following microbial pathogen challenge remains uncertain. Mice deficient in TSP-1 (thbs1(-/-)) showed enhanced lung bacterial clearance, reduced splenic dissemination, and increased survival compared with wild-type (WT) controls during intrapulmonary Klebsiella pneumoniae infection. More effective pathogen containment was associated with reduced burden of inflammation in thbs1(-/-) mouse lungs compared with WT controls. Lung NE activity was increased in thbs1(-/-) mice following K. pneumoniae challenge, and thbs1(-/-) neutrophils showed enhanced intracellular microbial killing that was abrogated with recombinant TSP-1 administration or WT serum. Thbs1(-/-) neutrophils exhibited enhanced NE and CG enzymatic activity, and a peptide corresponding to amino-acid residues 793-801 within the type-III repeat domain of TSP-1 bridled neutrophil proteolytic function and microbial killing in vitro. Thus, TSP-1 restrains proteolytic action during neutrophilic inflammation elicited by K. pneumoniae, providing a mechanism that may regulate the microbial killing arsenal. PMID:25492474

  13. A method to restrain the charging effect on an insulating substrate in high energy electron beam lithography

    NASA Astrophysics Data System (ADS)

    Mingyan, Yu; Shirui, Zhao; Yupeng, Jing; Yunbo, Shi; Baoqin, Chen

    2014-12-01

    Pattern distortions caused by the charging effect should be reduced while using the electron beam lithography process on an insulating substrate. We have developed a novel process by using the SX AR-PC 5000/90.1 solution as a spin-coated conductive layer, to help to fabricate nanoscale patterns of poly-methyl-methacrylate polymer resist on glass for phased array device application. This method can restrain the influence of the charging effect on the insulating substrate effectively. Experimental results show that the novel process can solve the problems of the distortion of resist patterns and electron beam main field stitching error, thus ensuring the accuracy of the stitching and overlay of the electron beam lithography system. The main characteristic of the novel process is that it is compatible to the multi-layer semiconductor process inside a clean room, and is a green process, quite simple, fast, and low cost. It can also provide a broad scope in the device development on insulating the substrate, such as high density biochips, flexible electronics and liquid crystal display screens.

  14. Proliferation of Estrogen Receptor alpha Positive Mammary Epithelial Cells is Restrained by TGFbeta1 in Adult Mice

    SciTech Connect

    Ewan, Kenneth B.R.; Oketch-Rabah, Hellen A.; Ravani, Shraddha A.; Shyamala, G.; Moses, Harold L.; Barcellos-Hoff, Mary Helen

    2005-03-03

    Transforming growth factor {beta}1 (TGF{beta}1) is a potent inhibitor of mammary epithelial proliferation. In human breast, estrogen receptor {alpha} (ER{alpha}) cells rarely co-localize with markers of proliferation, but their increased frequency correlates with breast cancer risk. To determine whether TGF{beta}1 is necessary for the quiescence of ER{alpha}-positive population, we examined mouse mammary epithelial gland at estrus. Approximately 35% of cells showed TGF{beta}1 activation, which co-localized with nuclear receptor-phosphorylated Smad 2/3, indicating that TGF{beta} signaling is autocrine. Furthermore, nuclear Smad co-localized with nuclear ER{alpha}. To test whether TGF{beta} was functional, we examined genetically engineered mice with different levels of TGF{beta}1. ER{alpha} co-localization with markers of proliferation (i.e. Ki-67 or BrdU) at estrus was significantly increased in the mammary glands of Tgf{beta}1 C57/bl/129SV heterozygote mice. This relationship was maintained following pregnancy, but was absent at puberty. Conversely, mammary epithelial expression of constitutively active TGF{beta}1 via the MMTV promoter suppressed proliferation of ER{alpha} positive cells. Thus, TGF{beta}1 activation functionally restrains ER{alpha} positive cells from proliferating in adult mammary gland. Accordingly, we propose that TGF{beta}1 dysregulation may promote proliferation of ER{alpha} positive cells associated with breast cancer risk in humans.

  15. The Rho-GTPase Rnd1 Suppresses Mammary Tumorigenesis and EMT by Restraining Ras-MAPK signaling

    PubMed Central

    Okada, Tomoyo; Sinha, Surajit; Esposito, Ilaria; Schiavon, Gaia; López-Lago, Miguel A.; Su, Wenjing; Pratilas, Christine A.; Abele, Cristina; Hernandez, Jonathan M.; Ohara, Masahiro; Okada, Morihito; Viale, Agnes; Heguy, Adriana; Socci, Nicholas D.; Sapino, Anna; Seshan, Venkatraman E.; Long, Stephen; Inghirami, Giorgio; Rosen, Neal; Giancotti, Filippo G.

    2015-01-01

    SUMMARY We identified the Rho-GTPase Rnd1 as a candidate metastasis suppressor through bioinformatics analysis and showed that its depletion disrupt epithelial adhesion and polarity, induced Epithelial-to-Mesenchymal Transition (EMT), and cooperated with deregulated expression of c-Myc or loss of p53 to cause neoplastic conversion. Mechanistic studies revealed that Rnd1 suppresses Ras signalling by activating the GAP domain of Plexin B1, which inhibits Rap1. Rap1 inhibition in turn led to derepression of p120-RasGAP, which was able to inhibit Ras. Inactivation of Rnd1 in mammary epithelial cells induced highly undifferentiated and invasive tumors in mice. Conversely, Rnd1 expression inhibited spontaneous and experimental lung colonization in mouse models of metastasis. Genomic studies indicated that gene deletion in combination with epigenetic silencing or, more rarely, point mutation inactivates RND1 in human breast cancer. These results reveal a previously unappreciated mechanism through which Rnd1 restrains activation of Ras-MAPK signaling and breast tumor initiation and progression. PMID:25531777

  16. Antimicrobial use in swine production and its effect on the swine gut microbiota and antimicrobial resistance.

    PubMed

    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. PMID:26414105

  17. Comparison of Thoracic Injury Risk in Frontal Car Crashes for Occupant Restrained without Belt Load Limiters and Those Restrained with 6 kN and 4 kN Belt Load Limiters.

    PubMed

    Foret-Bruno, J Y; Trosseille, X; Page, Y; Huère, J F; Le Coz, J Y; Bendjellal, F; Diboine, A; Phalempin, T; Villeforceix, D; Baudrit, P; Guillemot, H; Coltat, J C

    2001-11-01

    In France, as in other countries, accident research studies show that a large proportion of restrained occupants who sustain severe or fatal injuries are involved in frontal impacts (65% and 50%, respectively). In severe frontal impacts with restrained occupants and where intrusion is not preponderant, the oldest occupants very often sustain severe thoracic injuries due to the conventional seat belt. As we have been observing over the last years, we will expect in the coming years developments which include more solidly-built cars, as offset crash test procedures are widely used to evaluate the passive safety of production vehicles. The reduction of intrusion for the most severe frontal impacts, through optimization of car deformation, usually translates into an increase in restraint forces and hence thoracic injury risk with a conventional retractor seat belt for a given impact severity. It is, therefore essential to limit the restraint forces exerted by the seat belt on the thorax in order to reduce the number of road casualties. In order to address thoracic injury risk in frontal impact, Renault cars have been equipped with the Programmed Restraint System (PRS) since 1995. The PRS is a restraint system that combines belt load limitation and pyrotechnic belt pretension. In an initial design of the Programmed Restraint System (PRS1), the belt load limiter was a steel component designed to shear at a given shoulder force, namely 6 kN. It was mounted between the retractor and the lower anchorage point of the belt. The design of the PRS was modified in 1998 (PRS2), but the principle of load limitation was maintained. The threshold was decreased to 4 kN and this lower belt belt-force limiter has been combined with a specially designed airbag. This paper reports on 347 real-world frontal accidents where the EES (Equivalent Energy Speed) ranged from 35 to 75 km/h. One hundred and ninety-eight (198) of these accidents involved cars equipped with the 6 kN load limiter

  18. Antimicrobial resistance issues in beef production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  19. Synthesis and antimicrobial studies of chalconyl pregnenolones.

    PubMed

    Banday, Abid H; Iqbal Zargar, M; Ganaie, Bashir A

    2011-11-01

    An efficient and facile synthesis of 17-chalconyl derivatives of pregnenolone and their evaluation as antimicrobial agents against various microbial strains is reported. The scheme involves the transformation of the starting pregnenolone acetate into pregnenolone, conversion of pregnenolone to the corresponding chalcone derivatives. The compounds 3a-3j showed significant antimicrobial activity against all microbial strains used for testing. PMID:21771607

  20. TESTING ANTIMICROBIAL EFFICACY ON POROUS MATERIALS

    EPA Science Inventory

    The efficacy of antimicrobial treatments to eliminate or control biological growth in the indoor environment can easily be tested on nonporous surfaces. However, the testing of antimicrobial efficacy on porous surfaces, such as those found in the indoor environment [i.e., gypsum ...

  1. Antimicrobial susceptibility testing for Mycobacterium sp.

    PubMed

    Blanco-Ruano, Delia; Roberts, David M; Gonzalez-Del-Rio, Ruben; Álvarez, Daniel; Rebollo, Ma José; Pérez-Herrán, Esther; Mendoza, Alfonso

    2015-01-01

    The concept of antimicrobial susceptibility testing is an essential part of clinical microbiology. Antimicrobial testing has played a central role in the identification of new antibiotics and defining their clinical uses. Here we describe different approaches to determine the activity of compounds in medium- or high-throughput format. PMID:25779321

  2. Antimicrobial food packaging: potential and pitfalls

    PubMed Central

    Malhotra, Bhanu; Keshwani, Anu; Kharkwal, Harsha

    2015-01-01

    Nowadays food preservation, quality maintenance, and safety are major growing concerns of the food industry. It is evident that over time consumers’ demand for natural and safe food products with stringent regulations to prevent food-borne infectious diseases. Antimicrobial packaging which is thought to be a subset of active packaging and controlled release packaging is one such promising technology which effectively impregnates the antimicrobial into the food packaging film material and subsequently delivers it over the stipulated period of time to kill the pathogenic microorganisms affecting food products thereby increasing the shelf life to severe folds. This paper presents a picture of the recent research on antimicrobial agents that are aimed at enhancing and improving food quality and safety by reduction of pathogen growth and extension of shelf life, in a form of a comprehensive review. Examination of the available antimicrobial packaging technologies is also presented along with their significant impact on food safety. This article entails various antimicrobial agents for commercial applications, as well as the difference between the use of antimicrobials under laboratory scale and real time applications. Development of resistance amongst microorganisms is considered as a future implication of antimicrobials with an aim to come up with actual efficacies in extension of shelf life as well as reduction in bacterial growth through the upcoming and promising use of antimicrobials in food packaging for the forthcoming research down the line. PMID:26136740

  3. An Ecological Perspective on Antimicrobial Resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bacteria are ubiquitous, covering every ecological niche known to man. Within these ecological niches bacterial populations adapt to ensure their survival and the development of antimicrobial resistance is an example of a bacterium's ability to adapt and survive. Resistance to antimicrobials often ...

  4. National Antimicrobial Resistance Monitoring System (NARMS) Program

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The National Antimicrobial Resistance Monitoring System (NARMS) – Enteric Bacteria is a national public health surveillance system in the United States that tracks changes in the susceptibility of certain enteric bacteria to antimicrobial agents of human and veterinary medical importance. The NARMS ...

  5. Cationic Antimicrobial Polymers and Their Assemblies

    PubMed Central

    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

  6. ANTIMICROBIAL PROPERTIES OF IXORA COCCINEA L. (RUBIACEAE)

    PubMed Central

    Latha, P.G.; Abraham, T.K.; Panikkar, K.R.

    1995-01-01

    Antimicrobial activity was detected in the 50% ethanolic extract of Ixora coccinea. The effective inhibitory concentration of the extract against both the bacterial test organisms and the fungal test organisms studied was 125 ug mL-1, beyond which the inhibitory activity declined and the organisms started reviving from the effect of the antimicrobial principle. PMID:22556712

  7. Antimicrobial properties of ixora coccinea L. (Rubiaceae).

    PubMed

    Latha, P G; Abraham, T K; Panikkar, K R

    1995-04-01

    Antimicrobial activity was detected in the 50% ethanolic extract of Ixora coccinea. The effective inhibitory concentration of the extract against both the bacterial test organisms and the fungal test organisms studied was 125 ug mL(-1), beyond which the inhibitory activity declined and the organisms started reviving from the effect of the antimicrobial principle. PMID:22556712

  8. Synthesis and antimicrobial activity of squalamine analogue.

    PubMed

    Kim, H S; Choi, B S; Kwon, K C; Lee, S O; Kwak, H J; Lee, C H

    2000-08-01

    Synthesis and antimicrobial activity of squalamine analogue 2 are reported. The synthesis of 2 was accomplished from bisnoralcohol 3. The spermidine moiety was introduced via reductive amination of an appropriately functionalized 3beta-aminosterol with spermidinyl aldehyde 17 utilizing sodium triacetoxyborohydride as the reducing agent. Compound 2 shows weaker antimicrobial activity than squalamine. PMID:11003150

  9. Antimicrobial peptides: premises and promises.

    PubMed

    Reddy, K V R; Yedery, R D; Aranha, C

    2004-12-01

    Antimicrobial peptides (AMPs) are an important component of the natural defences of most living organisms against invading pathogens. These are relatively small (< 10kDa), cationic and amphipathic peptides of variable length, sequence and structure. During the past two decades several AMPs have been isolated from a wide variety of animals, both vertebrates and invertebrates, and plants as well as from bacteria and fungi. Most of these peptides are obtained from different sources like macrophages, neutrophils, epithelial cells, haemocytes, fat body, reproductive tract, etc. These peptides exhibit broad-spectrum activity against a wide range of microorganisms including Gram-positive and Gram-negative bacteria, protozoa, yeast, fungi and viruses. A few peptides have also been found to be cytotoxic to sperm and tumour cells. AMPs are classified based on the three dimensional structural studies carried out with the help of NMR. The peptides are broadly classified into five major groups namely (a) peptides that form alpha-helical structures, (b) peptides rich in cysteine residues, (c) peptides that form beta-sheet, (d) peptides rich in regular amino acids namely histatin, arginine and proline and (e) peptides composed of rare and modified amino acids. Most of these peptides are believed to act by disrupting the plasma membrane leading to the lysis of the cell. AMPs have been found to be excellent candidates for developing novel antimicrobial agents and a few of these peptides show antimicrobial activity against pathogens causing sexually transmitted infection (STI), including HIV/HSV. Peptides, namely magainin and nisin have been shown to demonstrate contraceptive properties in vitro and in vivo. A few peptides have already entered clinical trials for the treatment of impetigo, diabetic foot ulcers and gastric helicobacter infections. In this review, we discuss the source, structures and mode of action with special reference to therapeutic considerations of various AMPs

  10. Antimicrobial edible films and coatings.

    PubMed

    Cagri, Arzu; Ustunol, Zeynep; Ryser, Elliot T

    2004-04-01

    Increasing consumer demand for microbiologically safer foods, greater convenience, smaller packages, and longer product shelf life is forcing the industry to develop new food-processing, cooking, handling, and packaging strategies. Nonfluid ready-to-eat foods are frequently exposed to postprocess surface contamination, leading to a reduction in shelf life. The food industry has at its disposal a wide range of nonedible polypropylene- and polyethylene-based packaging materials and various biodegradable protein- and polysaccharide-based edible films that can potentially serve as packaging materials. Research on the use of edible films as packaging materials continues because of the potential for these films to enhance food quality, food safety, and product shelf life. Besides acting as a barrier against mass diffusion (moisture, gases, and volatiles), edible films can serve as carriers for a wide range of food additives, including flavoring agents, antioxidants, vitamins, and colorants. When antimicrobial agents such as benzoic acid, sorbic acid, propionic acid, lactic acid, nisin, and lysozyme have been incorporated into edible films, such films retarded surface growth of bacteria, yeasts, and molds on a wide range of products, including meats and cheeses. Various antimicrobial edible films have been developed to minimize growth of spoilage and pathogenic microorganisms, including Listeria monocytogenes, which may contaminate the surface of cooked ready-to-eat foods after processing. Here, we review the various types of protein-based (wheat gluten, collagen, corn zein, soy, casein, and whey protein), polysaccharide-based (cellulose, chitosan, alginate, starch, pectin, and dextrin), and lipid-based (waxes, acylglycerols, and fatty acids) edible films and a wide range of antimicrobial agents that have been or could potentially be incorporated into such films during manufacture to enhance the safety and shelf life of ready-to-eat foods. PMID:15083740

  11. Antimicrobial Resistance in the Environment.

    PubMed

    Williams, Maggie R; Stedtfeld, Robert D; Guo, Xueping; Hashsham, Syed A

    2016-10-01

    This review summarizes important publications from 2015 pertaining to the occurrence of antimicrobial resistance (AMR) in the environment. Emphasis is placed on sources of antibiotic resistance in the aquatic environment including wastewater treatment plants, hospitals, and agriculture, treatment and mitigation techniques, and surveillance and analysis methodologies for characterizing abundance data. As such, this review is organized into the following sections: i) occurrence of AMR in the environment, including surface waters, aquaculture, and wastewater ii) treatment technologies, and iii) technologies for rapid surveillance of AMR, iv) transmission between matrices, v) databases and analysis methods, and vi) gaps in AMR understanding. PMID:27620115

  12. The aversiveness of carbon dioxide stunning in pigs and a comparison of the CO(2) stunner crate vs. the V-restrainer.

    PubMed

    Jongman; Barnett; Hemsworth

    2000-03-22

    Using aversion learning techniques, the relative aversiveness of CO(2) to pigs in comparison to a shock with an electric prodder, and the aversiveness of a CO(2)-stunner crate in comparison to the aversiveness of a V-belt restrainer used for electric stunning were examined. The results showed that 90% CO(2) was considerably less aversive than an electric shock with a prodder. However, during exposure to 90% CO(2) all pigs lost conscious, which may have affected their memory of the procedure. The pigs remained conscious after exposure to 60% CO(2) and again showed virtually no aversion towards the stunner crate, while an electric shock with a prodder appeared highly aversive. The aversion to the V-restrainer belt and the CO(2) crate were similar. PMID:10719190

  13. Methods of Antimicrobial Coating of Diverse Materials

    NASA Technical Reports Server (NTRS)

    Akse, James R.; Holtsnider, John T.; Kliestik, Helen

    2011-01-01

    Methods of coating diverse substrate materials with antimicrobial agents have been developed. Originally intended to reduce health risks to astronauts posed by pathogenic microorganisms that can grow on surfaces in spacecraft, these methods could also be used on Earth for example, to ensure sterility of surgical inserts and other medical equipment. The methods involve, generally, chemical preparation of substrate surfaces to enable attachment of antimicrobial molecules to the substrate surfaces via covalent bonds. Substrate materials that have been treated successfully include aluminum, glass, a corrosion-resistant nickel alloy, stainless steel, titanium, and poly(tetrafluoroethylene). Antimicrobial agents that have been successfully immobilized include antibiotics, enzymes, bacteriocins, bactericides, and fungicides. A variety of linkage chem istries were employed. Activity of antimicrobial coatings against gram-positive bacteria, gram-negative bacteria, and fungi was demonstrated. Results of investigations indicate that the most suitable combination of antimicrobial agent, substrate, and coating method depends upon the intended application.

  14. Application of natural antimicrobials for food preservation.

    PubMed

    Tiwari, Brijesh K; Valdramidis, Vasilis P; O'Donnell, Colm P; Muthukumarappan, Kasiviswanathan; Bourke, Paula; Cullen, P J

    2009-07-22

    In this review, antimicrobials from a range of plant, animal, and microbial sources are reviewed along with their potential applications in food systems. Chemical and biochemical antimicrobial compounds derived from these natural sources and their activity against a range of pathogenic and spoilage microorganisms pertinent to food, together with their effects on food organoleptic properties, are outlined. Factors influencing the antimicrobial activity of such agents are discussed including extraction methods, molecular weight, and agent origin. These issues are considered in conjunction with the latest developments in the quantification of the minimum inhibitory (and noninhibitory) concentration of antimicrobials and/or their components. Natural antimicrobials can be used alone or in combination with other novel preservation technologies to facilitate the replacement of traditional approaches. Research priorities and future trends focusing on the impact of product formulation, intrinsic product parameters, and extrinsic storage parameters on the design of efficient food preservation systems are also presented. PMID:19548681

  15. Inspiration or deflation? Feeling similar or dissimilar to slim and plus-size models affects self-evaluation of restrained eaters.

    PubMed

    Papies, Esther K; Nicolaije, Kim A H

    2012-01-01

    The present studies examined the effect of perceiving images of slim and plus-size models on restrained eaters' self-evaluation. While previous research has found that such images can lead to either inspiration or deflation, we argue that these inconsistencies can be explained by differences in perceived similarity with the presented model. The results of two studies (ns=52 and 99) confirmed this and revealed that restrained eaters with high (low) perceived similarity to the model showed more positive (negative) self-evaluations when they viewed a slim model, compared to a plus-size model. In addition, Study 2 showed that inducing in participants a similarities mindset led to more positive self-evaluations after viewing a slim compared to a plus-size model, but only among restrained eaters with a relatively high BMI. These results are discussed in the context of research on social comparison processes and with regard to interventions for protection against the possible detrimental effects of media images. PMID:21962524

  16. To eat or not to eat red meat. A closer look at the relationship between restrained eating and vegetarianism in college females.

    PubMed

    Forestell, Catherine A; Spaeth, Andrea M; Kane, Stephanie A

    2012-02-01

    Previous research has suggested that vegetarianism may serve as a mask for restrained eating. The purpose of this study was to compare the dietary habits and lifestyle behaviors of vegetarians (n=55), pesco-vegetarians (n=28), semi-vegetarians (n=29), and flexitarians (n=37), to omnivores (n=91), who do not restrict animal products from their diets. A convenience sample of college-age females completed questionnaires about their eating habits, food choice motivations, and personality characteristics. Results indicated that while vegetarians and pesco-vegetarians were more open to new experiences and less food neophobic, they were not more restrained than omnivores. Rather semi-vegetarians; those who restricted only red meat from their diet, and flexitarians; those who occasionally eat red meat, were significantly more restrained than omnivores. Whereas food choices of semi-vegetarians and flexitarians were motivated by weight control, vegetarians and pesco-vegetarians' food choices were motivated by ethical concerns. By focusing specifically on semi-vegetarian and flexitarian subgroups, more effective approaches can be developed to ensure that their concerns about weight loss do not lead to unhealthful or disordered eating patterns. PMID:22079892

  17. The effect of the Palmyra trough and Mesozoic structures on the Levant margin and the evolution of the Levant restraining bend

    NASA Astrophysics Data System (ADS)

    Ghalayini, Ramadan; Homberg, Catherine; Nader, Fadi

    2016-04-01

    The Levant margin is characterised today by a restraining bend, part of the Levant Fracture System. It has been affected throughout geological times by several tectonic events, marking this area with deep crustal faults oriented oblique to the main NNE trending sinistral strike-slip plate boundary. These faults, together with other structures along the Levant margin, are similar to those found eastward in the adjacent Palmyra Basin. However, it has been long claimed that the evolution of the Levant margin and the adjacent Palmyra Basin is independent of each other. In this study, we tested the hypothesis that the Palmyra Basin is extending westward to the Levant margin through analogue modelling. We changed the thickness of the silicone unit to simulate and examine the role of pre-existing oblique structures, believed to be part of the Palmyra Basin, on the development of the Levant restraining bend. Results indicated a great similarity between the model and the natural example asserting the effect of the pre-existing structures on the growth of the restraining bend. Consequently, the pre-existing structures must be part of the Palmyra trough and confirm that the latter is extending westward to the Levant margin which forms its westward termination.

  18. Worry or craving? A selective review of evidence for food-related attention biases in obese individuals, eating-disorder patients, restrained eaters and healthy samples.

    PubMed

    Werthmann, Jessica; Jansen, Anita; Roefs, Anne

    2015-05-01

    Living in an 'obesogenic' environment poses a serious challenge for weight maintenance. However, many people are able to maintain a healthy weight indicating that not everybody is equally susceptible to the temptations of this food environment. The way in which someone perceives and reacts to food cues, that is, cognitive processes, could underlie differences in susceptibility. An attention bias for food could be such a cognitive factor that contributes to overeating. However, an attention bias for food has also been implicated with restrained eating and eating-disorder symptomatology. The primary aim of the present review was to determine whether an attention bias for food is specifically related to obesity while also reviewing evidence for attention biases in eating-disorder patients, restrained eaters and healthy-weight individuals. Another aim was to systematically examine how selective attention for food relates (causally) to eating behaviour. Current empirical evidence on attention bias for food within obese samples, eating-disorder patients, and, even though to a lesser extent, in restrained eaters is contradictory. However, present experimental studies provide relatively consistent evidence that an attention bias for food contributes to subsequent food intake. This review highlights the need to distinguish not only between different (temporal) attention bias components, but also to take different motivations (craving v. worry) and their impact on attentional processing into account. Overall, the current state of research suggests that biased attention could be one important cognitive mechanism by which the food environment tempts us into overeating. PMID:25311212

  19. Antimicrobial outcomes in plasma medicine

    NASA Astrophysics Data System (ADS)

    Ryan, Thomas P.; Stalder, Kenneth R.; Woloszko, Jean

    2015-03-01

    Plasma is referred to as the fourth state of matter and is frequently generated in the environment of a strong electric field. The result consists of highly reactive species--ions, electrons, reactive atoms and molecules, and UV radiation. Plasma Medicine unites a number of fields, including Physics, Plasma Chemistry, Cell Biology, Biochemistry, and Medicine. The treatment modality utilizes Cold Atmospheric Plasma (CAP), which is able to sterilize and treat microbes in a nonthermal manner. These gas-based plasma systems operate at close to room temperature and atmospheric pressure, making them very practical for a range of potential treatments and are highly portable for clinical use throughout the health care system. The hypothesis is that gas based plasma kills bacteria, fungus, and viruses but spares mammalian cells. This paper will review systematic work which shows examples of systems and performance in regards to antimicrobial effects and the sparing of mammalian cells. The mechanism of action will be discussed, as well as dosing for the treatment of microbial targets, including sterilization processes, another important healthcare need. In addition, commercial systems will be overviewed and compared, along with evidence-based, patient results. The range of treatments cover wound treatment and biofilms, as well as antimicrobial treatment, with little chance for resistance and tolerance, as in drug regimens. Current clinical studies include applications in dentistry, food treatment, cancer treatment, wound treatment for bacteria and biofilms, and systems to combat health care related infections.

  20. Combination Effects of Antimicrobial Peptides

    PubMed Central

    Yu, Guozhi; Baeder, Desiree Y.; Regoes, Roland R.

    2016-01-01

    Antimicrobial peptides (AMPs) are ancient and conserved across the tree of life. Their efficacy over evolutionary time has been largely attributed to their mechanisms of killing. Yet, the understanding of their pharmacodynamics both in vivo and in vitro is very limited. This is, however, crucial for applications of AMPs as drugs and also informs the understanding of the action of AMPs in natural immune systems. Here, we selected six different AMPs from different organisms to test their individual and combined effects in vitro. We analyzed their pharmacodynamics based on the Hill function and evaluated the interaction of combinations of two and three AMPs. Interactions of AMPs in our study were mostly synergistic, and three-AMP combinations displayed stronger synergism than two-AMP combinations. This suggests synergism to be a common phenomenon in AMP interaction. Additionally, AMPs displayed a sharp increase in killing within a narrow dose range, contrasting with those of antibiotics. We suggest that our results could lead a way toward better evaluation of AMP application in practice and shed some light on the evolutionary consequences of antimicrobial peptide interactions within the immune system of organisms. PMID:26729502

  1. Antimicrobial Peptides: Versatile Biological Properties

    PubMed Central

    Pushpanathan, Muthuirulan; Rajendhran, Jeyaprakash

    2013-01-01

    Antimicrobial peptides are diverse group of biologically active molecules with multidimensional properties. In recent past, a wide variety of AMPs with diverse structures have been reported from different sources such as plants, animals, mammals, and microorganisms. The presence of unusual amino acids and structural motifs in AMPs confers unique structural properties to the peptide that attribute for their specific mode of action. The ability of these active AMPs to act as multifunctional effector molecules such as signalling molecule, immune modulators, mitogen, antitumor, and contraceptive agent makes it an interesting candidate to study every aspect of their structural and biological properties for prophylactic and therapeutic applications. In addition, easy cloning and recombinant expression of AMPs in heterologous plant host systems provided a pipeline for production of disease resistant transgenic plants. Besides these properties, AMPs were also used as drug delivery vectors to deliver cell impermeable drugs to cell interior. The present review focuses on the diversity and broad spectrum antimicrobial activity of AMPs along with its multidimensional properties that could be exploited for the application of these bioactive peptides as a potential and promising drug candidate in pharmaceutical industries. PMID:23935642

  2. Structural refinement from restrained-ensemble simulations based on EPR/DEER data: application to T4 lysozyme.

    PubMed

    Islam, Shahidul M; Stein, Richard A; McHaourab, Hassane S; Roux, Benoît

    2013-05-01

    DEER (double electron-electron resonance) is a powerful pulsed ESR (electron spin resonance) technique allowing the determination of distance histograms between pairs of nitroxide spin-labels linked to a protein in a native-like solution environment. However, exploiting the huge amount of information provided by ESR/DEER histograms to refine structural models is extremely challenging. In this study, a restrained ensemble (RE) molecular dynamics (MD) simulation methodology is developed to address this issue. In RE simulation, the spin-spin distance distribution histograms calculated from a multiple-copy MD simulation are enforced, via a global ensemble-based energy restraint, to match those obtained from ESR/DEER experiments. The RE simulation is applied to 51 ESR/DEER distance histogram data from spin-labels inserted at 37 different positions in T4 lysozyme (T4L). The rotamer population distribution along the five dihedral angles connecting the nitroxide ring to the protein backbone is determined and shown to be consistent with available information from X-ray crystallography. For the purpose of structural refinement, the concept of a simplified nitroxide dummy spin-label is designed and parametrized on the basis of these all-atom RE simulations with explicit solvent. It is demonstrated that RE simulations with the dummy nitroxide spin-labels imposing the ESR/DEER experimental distance distribution data are able to systematically correct and refine a series of distorted T4L structures, while simple harmonic distance restraints are unsuccessful. This computationally efficient approach allows experimental restraints from DEER experiments to be incorporated into RE simulations for efficient structural refinement. PMID:23510103

  3. 11β-Hydroxysteroid Dehydrogenase Type 1 Is Expressed in Neutrophils and Restrains an Inflammatory Response in Male Mice

    PubMed Central

    Coutinho, Agnes E.; Kipari, Tiina M. J.; Zhang, Zhenguang; Esteves, Cristina L.; Lucas, Christopher D.; Gilmour, James S.; Webster, Scott P.; Walker, Brian R.; Hughes, Jeremy; Savill, John S.; Seckl, Jonathan R.; Rossi, Adriano G.

    2016-01-01

    Endogenous glucocorticoid action within cells is enhanced by prereceptor metabolism by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), which converts intrinsically inert cortisone and 11-dehydrocorticosterone into active cortisol and corticosterone, respectively. 11β-HSD1 is highly expressed in immune cells elicited to the mouse peritoneum during thioglycollate-induced peritonitis and is down-regulated as the inflammation resolves. During inflammation, 11β-HSD1-deficient mice show enhanced recruitment of inflammatory cells and delayed acquisition of macrophage phagocytic capacity. However, the key cells in which 11β-HSD1 exerts these effects remain unknown. Here we have identified neutrophils (CD11b+,Ly6G+,7/4+ cells) as the thioglycollate-recruited cells that most highly express 11β-HSD1 and show dynamic regulation of 11β-HSD1 in these cells during an inflammatory response. Flow cytometry showed high expression of 11β-HSD1 in peritoneal neutrophils early during inflammation, declining at later states. In contrast, expression in blood neutrophils continued to increase during inflammation. Ablation of monocytes/macrophages by treatment of CD11b-diphtheria-toxin receptor transgenic mice with diphtheria toxin prior to thioglycollate injection had no significant effect on 11β-HSD1 activity in peritoneal cells, consistent with neutrophils being the predominant 11β-HSD1 expressing cell type at this time. Similar to genetic deficiency in 11β-HSD1, acute inhibition of 11β-HSD1 activity during thioglycollate-induced peritonitis augmented inflammatory cell recruitment to the peritoneum. These data suggest that neutrophil 11β-HSD1 increases during inflammation to contribute to the restraining effect of glucocorticoids upon neutrophil-mediated inflammation. In human neutrophils, lipopolysaccharide activation increased 11β-HSD1 expression, suggesting the antiinflammatory effects of 11β-HSD1 in neutrophils may be conserved in humans. PMID:27145012

  4. A non-human primate model of bipedal locomotion under restrained condition allowing gait studies and single unit brain recordings.

    PubMed

    Goetz, L; Piallat, B; Thibaudier, Y; Montigon, O; David, O; Chabardès, S

    2012-03-15

    For decades, several animal models of locomotion have allowed a better understanding of the basic physiological mechanisms of gait. However, unlike most of the mammals, the Order Primates is characterized by fundamental changes in locomotor behaviour. In particular, some primates use a specific pattern of locomotion and are able to naturally walk bipedally due possibly to a specific supra-spinal control of locomotion. These features must be taken into account when one considers to study the intrinsic properties of human gait. Thus, an experimental model of bipedal locomotion allowing precise and reproducible analysis of gait in non-human primate is still lacking. This study describes a non-human primate model of bipedal locomotion under restrained condition. We undertook a kinematic and biomechanic study in three Macaca fascicularis trained to walk bipedally on a treadmill. One of the primate was evaluated in complete head fixation. Gait visual analysis and electromyographic recordings provided pertinent description of the gait pattern. Step frequencies, step lengths, cycle and stance phase durations were correlated with Froude number (dimensionless velocity), whereas swing phase durations remained non-correlated. Gait patterns observed in our model were similar to those obtained in freely bipedal Macaca fuscata and to a lesser extend to Humans. Gait pattern was not modified by head fixation thereby allowing us to perform precise and repetitive micro electrode recordings of deep cerebral structures. Thus, the present model could provide a pertinent pre-clinical tool to study gait parameters and their neuronal control but also could be helpful to validate new therapeutics interventions. PMID:22155386

  5. Resveratrol mitigate structural changes and hepatic stellate cell activation in N'-nitrosodimethylamine-induced liver fibrosis via restraining oxidative damage.

    PubMed

    Ahmad, Areeba; Ahmad, Riaz

    2014-09-25

    resveratrol is due to restrained oxidative damage and down-regulation of α-SMA, which inhibits HSC activation to obstruct liver fibrosis. PMID:25064540

  6. Diurnal, seasonal, and sex patterns of heart rate in grip-restrained African giant rats (Cricetomys gambianus, Waterhouse).

    PubMed

    Dzenda, Tavershima; Ayo, Joseph O; Sinkalu, Victor O; Yaqub, Lukuman S

    2015-10-01

    This study was carried out to determine heart rate (HR) values, including diurnal, seasonal, and sex patterns, in the African giant rat (Cricetomys gambianus, Waterhouse). HR was measured using stethoscope in grip-restrained African giant rats of either sex (103 bucks and 98 does), live-trapped from a tropical Savannah, and caged individually in the laboratory during the harmattan (cold-dry), hot-dry, and rainy seasons over a 3-year period. The HR fluctuated between 90 and 210 beats per minute (bpm) throughout the study period. Diurnal changes in HR (mean ± SEM) during the hot-dry and rainy seasons were nonsignificant (P > 0.05), but the morning and afternoon values differed (P < 0.01) during the cold-dry season. The HR varied (P < 0.05) among seasons, with peak, nadir, and moderate values recorded during the cold-dry (165.8 ± 0.51 bpm), hot-dry (153.1 ± 0.74 bpm), and rainy (163.4 ± 0.70 bpm) seasons, respectively. Mean HR of bucks was lower than that of does during the cold-dry (P < 0.0001) and hot-dry (P < 0.01) seasons, but sex difference during the rainy season was insignificant (P > 0.05). Overall, mean HR was lower (P < 0.0001) in bucks (158.8 ± 0.53 bpm) than in does (164.8 ± 0.53 bpm). In conclusion, values of HR in African giant rats are shown for the first time. Season, sex, and daytime influenced the HR, and should be considered during clinical evaluations of the rats. PMID:26471756

  7. E2F7 regulates transcription and maturation of multiple microRNAs to restrain cell proliferation

    PubMed Central

    Mitxelena, Jone; Apraiz, Aintzane; Vallejo-Rodríguez, Jon; Malumbres, Marcos; Zubiaga, Ana M.

    2016-01-01

    E2F transcription factors (E2F1-8) are known to coordinately regulate the expression of a plethora of target genes, including those coding for microRNAs (miRNAs), to control cell cycle progression. Recent work has described the atypical E2F factor E2F7 as a transcriptional repressor of cell cycle-related protein-coding genes. However, the contribution of E2F7 to miRNA gene expression during the cell cycle has not been defined. We have performed a genome-wide RNA sequencing analysis to identify E2F7-regulated miRNAs and show that E2F7 plays as a major role in the negative regulation of a set of miRNAs that promote cellular proliferation. We provide mechanistic evidence for an interplay between E2F7 and the canonical E2F factors E2F1-3 in the regulation of multiple miRNAs. We show that miR-25, -26a, -27b, -92a and -7 expression is controlled at the transcriptional level by the antagonistic activity of E2F7 and E2F1-3. By contrast, let-7 miRNA expression is controlled indirectly through a novel E2F/c-MYC/LIN28B axis, whereby E2F7 and E2F1-3 modulate c-MYC and LIN28B levels to impact let-7 miRNA processing and maturation. Taken together, our data uncover a new regulatory network involving transcriptional and post-transcriptional mechanisms controlled by E2F7 to restrain cell cycle progression through repression of proliferation-promoting miRNAs. PMID:26961310

  8. A Simple and Accurate Method To Calculate Free Energy Profiles and Reaction Rates from Restrained Molecular Simulations of Diffusive Processes.

    PubMed

    Ovchinnikov, Victor; Nam, Kwangho; Karplus, Martin

    2016-08-25

    A method is developed to obtain simultaneously free energy profiles and diffusion constants from restrained molecular simulations in diffusive systems. The method is based on low-order expansions of the free energy and diffusivity as functions of the reaction coordinate. These expansions lead to simple analytical relationships between simulation statistics and model parameters. The method is tested on 1D and 2D model systems; its accuracy is found to be comparable to or better than that of the existing alternatives, which are briefly discussed. An important aspect of the method is that the free energy is constructed by integrating its derivatives, which can be computed without need for overlapping sampling windows. The implementation of the method in any molecular simulation program that supports external umbrella potentials (e.g., CHARMM) requires modification of only a few lines of code. As a demonstration of its applicability to realistic biomolecular systems, the method is applied to model the α-helix ↔ β-sheet transition in a 16-residue peptide in implicit solvent, with the reaction coordinate provided by the string method. Possible modifications of the method are briefly discussed; they include generalization to multidimensional reaction coordinates [in the spirit of the model of Ermak and McCammon (Ermak, D. L.; McCammon, J. A. J. Chem. Phys. 1978, 69, 1352-1360)], a higher-order expansion of the free energy surface, applicability in nonequilibrium systems, and a simple test for Markovianity. In view of the small overhead of the method relative to standard umbrella sampling, we suggest its routine application in the cases where umbrella potential simulations are appropriate. PMID:27135391

  9. 11β-Hydroxysteroid Dehydrogenase Type 1 Is Expressed in Neutrophils and Restrains an Inflammatory Response in Male Mice.

    PubMed

    Coutinho, Agnes E; Kipari, Tiina M J; Zhang, Zhenguang; Esteves, Cristina L; Lucas, Christopher D; Gilmour, James S; Webster, Scott P; Walker, Brian R; Hughes, Jeremy; Savill, John S; Seckl, Jonathan R; Rossi, Adriano G; Chapman, Karen E

    2016-07-01

    Endogenous glucocorticoid action within cells is enhanced by prereceptor metabolism by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), which converts intrinsically inert cortisone and 11-dehydrocorticosterone into active cortisol and corticosterone, respectively. 11β-HSD1 is highly expressed in immune cells elicited to the mouse peritoneum during thioglycollate-induced peritonitis and is down-regulated as the inflammation resolves. During inflammation, 11β-HSD1-deficient mice show enhanced recruitment of inflammatory cells and delayed acquisition of macrophage phagocytic capacity. However, the key cells in which 11β-HSD1 exerts these effects remain unknown. Here we have identified neutrophils (CD11b(+),Ly6G(+),7/4(+) cells) as the thioglycollate-recruited cells that most highly express 11β-HSD1 and show dynamic regulation of 11β-HSD1 in these cells during an inflammatory response. Flow cytometry showed high expression of 11β-HSD1 in peritoneal neutrophils early during inflammation, declining at later states. In contrast, expression in blood neutrophils continued to increase during inflammation. Ablation of monocytes/macrophages by treatment of CD11b-diphtheria-toxin receptor transgenic mice with diphtheria toxin prior to thioglycollate injection had no significant effect on 11β-HSD1 activity in peritoneal cells, consistent with neutrophils being the predominant 11β-HSD1 expressing cell type at this time. Similar to genetic deficiency in 11β-HSD1, acute inhibition of 11β-HSD1 activity during thioglycollate-induced peritonitis augmented inflammatory cell recruitment to the peritoneum. These data suggest that neutrophil 11β-HSD1 increases during inflammation to contribute to the restraining effect of glucocorticoids upon neutrophil-mediated inflammation. In human neutrophils, lipopolysaccharide activation increased 11β-HSD1 expression, suggesting the antiinflammatory effects of 11β-HSD1 in neutrophils may be conserved in humans. PMID:27145012

  10. Diurnal, seasonal, and sex patterns of heart rate in grip-restrained African giant rats (Cricetomys gambianus, Waterhouse)

    PubMed Central

    Dzenda, Tavershima; Ayo, Joseph O; Sinkalu, Victor O; Yaqub, Lukuman S

    2015-01-01

    This study was carried out to determine heart rate (HR) values, including diurnal, seasonal, and sex patterns, in the African giant rat (Cricetomys gambianus, Waterhouse). HR was measured using stethoscope in grip-restrained African giant rats of either sex (103 bucks and 98 does), live-trapped from a tropical Savannah, and caged individually in the laboratory during the harmattan (cold-dry), hot-dry, and rainy seasons over a 3-year period. The HR fluctuated between 90 and 210 beats per minute (bpm) throughout the study period. Diurnal changes in HR (mean ± SEM) during the hot-dry and rainy seasons were nonsignificant (P > 0.05), but the morning and afternoon values differed (P < 0.01) during the cold-dry season. The HR varied (P < 0.05) among seasons, with peak, nadir, and moderate values recorded during the cold-dry (165.8 ± 0.51 bpm), hot-dry (153.1 ± 0.74 bpm), and rainy (163.4 ± 0.70 bpm) seasons, respectively. Mean HR of bucks was lower than that of does during the cold-dry (P < 0.0001) and hot-dry (P < 0.01) seasons, but sex difference during the rainy season was insignificant (P > 0.05). Overall, mean HR was lower (P < 0.0001) in bucks (158.8 ± 0.53 bpm) than in does (164.8 ± 0.53 bpm). In conclusion, values of HR in African giant rats are shown for the first time. Season, sex, and daytime influenced the HR, and should be considered during clinical evaluations of the rats. PMID:26471756

  11. Antimicrobial use and antimicrobial resistance in nosocomial pathogens at a tertiary care hospital in Pune

    PubMed Central

    Nair, Velu; Sharma, Dinesh; Sahni, A.K.; Grover, Naveen; Shankar, S.; Jaiswal, S.S.; Dalal, S.S.; Basannar, D.R.; Phutane, Vivek S.; Kotwal, Atul; Gopal Rao, G.; Batura, Deepak; Venkatesh, M.D.; Sinha, Tapan; Kumar, Sushil; Joshi, D.P.

    2015-01-01

    Background Resistance to antimicrobial agents is emerging in wide variety of nosocomial and community acquired pathogens. Widespread and often inappropriate use of broad spectrum antimicrobial agents is recognized as a significant contributing factor to the development and spread of bacterial resistance. This study was conducted to gain insight into the prevalent antimicrobial prescribing practices, and antimicrobial resistance pattern in nosocomial pathogens at a tertiary care hospital in Pune, India. Methods Series of one day cross sectional point prevalence surveys were carried out on four days between March and August 2014. All eligible in patients were included in the study. A structured data entry form was used to collect the data for each patient. Relevant samples were collected for microbiological examination from all the clinically identified hospital acquired infection cases. Results 41.73% of the eligible patients (95% CI: 39.52–43.97) had been prescribed at least one antimicrobial during their stay in the hospital. Beta-lactams (38%) were the most prescribed antimicrobials, followed by Protein synthesis inhibitors (24%). Majority of the organisms isolated from Hospital acquired infection (HAI cases) were found to be resistant to the commonly used antimicrobials viz: Cefotaxime, Ceftriaxone, Amikacin, Gentamicin and Monobactams. Conclusion There is need to have regular antimicrobial susceptibility surveillance and dissemination of this information to the clinicians. In addition, emphasis on the rational use of antimicrobials, antimicrobial rotation and strict adherence to the standard treatment guidelines is very essential. PMID:25859071

  12. 40 CFR 158.2201 - Antimicrobial use patterns.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Antimicrobial use patterns. 158.2201... DATA REQUIREMENTS FOR PESTICIDES Antimicrobial Pesticide Data Requirements § 158.2201 Antimicrobial use patterns. (a) Antimicrobial use patterns. The 12 general use patterns used in the data tables in...

  13. Danish Integrated Antimicrobial Resistance Monitoring and Research Program

    PubMed Central

    Heuer, Ole E.; Emborg, Hanne-Dorthe; Bagger-Skjøt, Line; Jensen, Vibeke F.; Rogues, Anne-Marie; Skov, Robert L.; Agersø, Yvonne; Brandt, Christian T.; Seyfarth, Anne Mette; Muller, Arno; Hovgaard, Karin; Ajufo, Justin; Bager, Flemming; Aarestrup, Frank M.; Frimodt-Møller, Niels; Wegener, Henrik C.; Monnet, Dominique L.

    2007-01-01

    Resistance to antimicrobial agents is an emerging problem worldwide. Awareness of the undesirable consequences of its widespread occurrence has led to the initiation of antimicrobial agent resistance monitoring programs in several countries. In 1995, Denmark was the first country to establish a systematic and continuous monitoring program of antimicrobial drug consumption and antimicrobial agent resistance in animals, food, and humans, the Danish Integrated Antimicrobial Resistance Monitoring and Research Program (DANMAP). Monitoring of antimicrobial drug resistance and a range of research activities related to DANMAP have contributed to restrictions or bans of use of several antimicrobial agents in food animals in Denmark and other European Union countries. PMID:18217544

  14. Clinical and Antibiofilm Efficacy of Antimicrobial Hydrogels

    PubMed Central

    Finnegan, Simon; Percival, Steven L.

    2015-01-01

    Significance: Hydrogels have been shown to have a significant role to play in wound healing. Hydrogels are used to assist in the management of dry, sloughy, or necrotic wounds. However, recent scientific evidence has shown that biofilms delay wound healing and increase a wound propensity to infection. It is therefore essential that hydrogels incorporating antimicrobials demonstrate efficacy on biofilms. Consequently, it is the aim of this article to review the efficacy of hydrogels, incorporating antimicrobials, on wounds with specific reference to their efficacy on biofilms. Recent Advances: Technologies being developed for the management of wounds are rapidly expanding. In particularly next-generation hydrogels, incorporating copolymers, have been reported to enable the smart release of antimicrobials. This has led to the development of a more tailored patient-specific antimicrobial hydrogel therapy. Critical Issues: Evidence relating to the efficacy of hydrogels, incorporating antimicrobials, on biofilms within both the in vitro and in vivo environments is lacking. Future Direction: Studies that investigate the efficacy of antimicrobial hydrogel wound dressings on both in vivo and in vitro biofilms are important. However, there is a significant need for better and more reproducible in vivo biofilm models. Until this is possible, data generated from appropriate and representative in vitro models will help to assist researchers and clinicians in evaluating antimicrobial and antibiofilm hydrogel technology for the extrapolation of efficacy data relevant to biofilms present in the in vivo environment. PMID:26155382

  15. Antimicrobial peptides in human skin disease

    PubMed Central

    Kenshi, Yamasaki; Richard, L. Gallo

    2009-01-01

    The skin continuously encounters microbial pathogens. To defend against this, cells of the epidermis and dermis have evolved several innate strategies to prevent infection. Antimicrobial peptides are one of the primary mechanisms used by the skin in the early stages of immune defense. In general, antimicrobial peptides have broad antibacterial activity against gram-positive and negative bacteria and also show antifungal and antiviral activity. The antimicrobial activity of most peptides occurs as a result of unique structural characteristics that enable them to disrupt the microbial membrane while leaving human cell membranes intact. However, antimicrobial peptides also act on host cells to stimulate cytokine production, cell migration, proliferation, maturation, and extracellular matrix synthesis. The production by human skin of antimicrobial peptides such as defensins and cathelicidins occurs constitutively but also greatly increases after infection, inflammation or injury. Some skin diseases show altered expression of antimicrobial peptides, partially explaining the pathophysiology of these diseases. Thus, current research suggests that understanding how antimicrobial peptides modify susceptibility to microbes, influence skin inflammation, and modify wound healing, provides greater insight into the pathophysiology of skin disorders and offers new therapeutic opportunities. PMID:18086583

  16. Remote Antimicrobial Stewardship in Community Hospitals

    PubMed Central

    Wood, Zachary H.; Nicolsen, Nicole C.; Allen, Nichole; Cook, Paul P.

    2015-01-01

    Antimicrobial stewardship has become standard practice at university medical centers, but the practice is more difficult to implement in remote community hospitals that lack infectious diseases trained practitioners. Starting in 2011, six community hospitals within the Vidant Health system began an antimicrobial stewardship program utilizing pharmacists who reviewed charts remotely from Vidant Medical Center. Pharmacists made recommendations within the electronic medical record (EMR) to streamline, discontinue, or switch antimicrobial agents. Totals of charts reviewed, recommendations made, recommendations accepted, and categories of intervention were recorded. Linear regression was utilized to measure changes in antimicrobial use over time. For the four larger hospitals, recommendations for changes were made in an average of 45 charts per month per hospital and physician acceptance of the pharmacists’ recommendations varied between 83% and 88%. There was no significant decrease in total antimicrobial use, but much of the use was outside of the stewardship program’s review. Quinolone use decreased by more than 50% in two of the four larger hospitals. Remote antimicrobial stewardship utilizing an EMR is feasible in community hospitals and is generally received favorably by physicians. As more community hospitals adopt EMRs, there is an opportunity to expand antimicrobial stewardship beyond the academic medical center. PMID:27025642

  17. Synthesis and conformational analysis by 1H NMR and restrained molecular dynamics simulations of the cyclic decapeptide [Ser-Tyr-Ser-Met-Glu-His-Phe-Arg-Trp-Gly].

    PubMed

    Buono, R A; Kucharczyk, N; Neuenschwander, M; Kemmink, J; Hwang, L Y; Fauchère, J L; Venanzi, C A

    1996-06-01

    The design of enzyme mimics with therapeutic and industrial applications has interested both experimental and computational chemists for several decades. Recent advances in the computational methodology of restrained molecular dynamics, used in conjunction with data obtained from two-dimensional 1H NMR spectroscopy, make it a promising method to study peptide and protein structure and function. Several issues, however, need to be addressed in order to assess the validity of this method for its explanatory and predictive value. Among the issues addressed in this study are: the accuracy and generizability of the GROMOS peptide molecular mechanics force field; the effect of inclusion of solvent on the simulations; and the effect of different types of restraining algorithms on the computational results. The decapeptide Ser-Tyr-Ser-Met-Glu-His-Phe-Arg-Trp-Gly, which corresponds to the sequence of ACTH1-10, has been synthesized, cyclized, and studied by two-dimensional 1H NMR spectroscopy. Restrained molecular dynamics (RMD) and time-averaged restrained molecular dynamics (TARMD) simulations were carried out on four different distance-geometry starting structures in order to determine and contrast the behavior of cyclic ACTH1-10 in vacuum and in solution. For the RMD simulations, the structures did not fit the NOE data well, even at high values of the restraining potential. The TARMD simulation method, however, was able to give structures that fit the NOE data at high values of the restraining potential. In both cases, inclusion of explicit solvent molecules in the simulation had little effect on the quality of the fit, although it was found to dampen the motion of the cyclic peptide. For both simulation techniques, the number and size of the NOE violations increased as the restraining potential approached zero. This is due, presumably, to inadequacies in the force field. Additional TARMD vacuum-phase simulations, run with a larger memory length or with a larger sampling

  18. Human Antimicrobial Peptides and Proteins

    PubMed Central

    Wang, Guangshun

    2014-01-01

    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 medicine to

  19. Antimicrobial Dose in Obese Patient

    PubMed Central

    Kassab, Sawsan; Syed Sulaiman, Syed Azhar; Abdul Aziz, Noorizan

    2007-01-01

    Introduction Obesity is a chronic disease that has become one of major public health issue in Malaysia because of its association with other disease states including cardiovascular disease and diabetes. Despite continuous efforts to educate the public about the health risks associated with obesity, prevalence of the disease continues to increase. Dosing of many medications are based on weight, limited data are available on how antimicrobial agents should be dosed in obesity. The aim of this case presentation is to discuss dose of antibiotic in obese patient. Case report: Patient: GMN, Malay, Female, 45 year old, 150kg, transferred from medical ward to ICU with problems of fever, orthopnea, sepsis secondary to nosocomial pneumonia. She was admitted to hospital a week ago for SOB on exertion, cyanosis, mildly dyspneic, somasthenia, bilateral ankle swelling. There was no fever, cough, chest pain, clubbing, flapping tremor. Her grand father has pre-morbid history of obesity, HPT, DM and asthma. She was non alcoholic, smoker, and not on diet control. The diagnosis Pickwickian syndrome was made. Patient was treated with IV Dopamine 11mcg/kg/min, IV Morphine 4mg/h. IV GTN 15mcg/min, IV Ca gluconate 10g/24h for 3/7, IV Zantac 50mg tds, IV Augmentin 1.2g tds, IV Lasix 40mg od, IV Plasil 10mg tds, S.c heparin 5000IU bd. patient become stable and moved to medical ward to continue her treatment. Discussion: The altered physiologic function seen in obese patients is a concern in patients receiving antimicrobial agents because therapeutic outcomes depend on achieving a minimum inhibitory concentration (MIC). The therapeutic effect of any drug can be altered when any of the 4 pharmacokinetic processes (absorption, distribution, metabolism, or elimination) are altered. Decreased blood flow rates and increased renal clearance in obese patients can affect drug distribution and elimination. Changes in serum protein levels can change the metabolism and distribution of drugs that are

  20. Antimicrobial activity of Epilobium spp. extracts.

    PubMed

    Battinelli, L; Tita, B; Evandri, M G; Mazzanti, G

    2001-01-01

    The antimicrobial activity of the Epilobium angustifolium, E. hirsutum, E. palustre, E. tetragonum and E. rosmarinifolium ethanolic extracts was studied in vitro on Gram-positive and Gram-negative bacteria, yeasts and fungi. The cytotoxicity of the extracts was also evaluated using the Artemia salina test. All the extracts showed antimicrobial activity in a range of concentrations between 10 and 650 microgml of dry extract. E. angustifolium and E. rosmarinifolium had the most broad spectrum of action inhibiting bacteria, yeasts and fungi. The extracts were devoid of toxicity on Artemia salina within the range of antimicrobial concentrations, suggesting that the action is selective on microorganisms. PMID:11482755

  1. [Antimicrobial peptide in dentisty. Literature review].

    PubMed

    Sato, F Simain; Rompen, E; Heinen, E

    2009-12-01

    The use of antimicrobial substances has contributed to the development of multiple antimicrobial resistances (1), challenging the pharmaceutical industry to develop with new, innovative, and effective molecules. Discovered around 1980, molecules called natural antimicrobial peptides (AMPs) appear to hold great potential for the treatment of infections. These cationic peptides are able to stop the bacterial development and to control infections. The purpose of this review is to help improve the understanding of the way AMPs operate in the context of the development of new cures against viruses, bacteria, and mushrooms found in the human body in general and in the oral cavity in particular. PMID:20143750

  2. Ultrashort Antimicrobial Peptides with Antiendotoxin Properties

    PubMed Central

    Chih, Ya-Han; Lin, Yen-Shan; Yip, Bak-Sau; Wei, Hsiu-Ju; Chu, Hung-Lun; Yu, Hui-Yuan; Cheng, Hsi-Tsung

    2015-01-01

    Release of lipopolysaccharide (LPS) (endotoxin) from bacteria into the bloodstream may cause serious unwanted stimulation of the host immune system. Some but not all antimicrobial peptides can neutralize LPS-stimulated proinflammatory responses. Salt resistance and serum stability of short antimicrobial peptides can be boosted by adding β-naphthylalanine to their termini. Herein, significant antiendotoxin effects were observed in vitro and in vivo with the β-naphthylalanine end-tagged variants of the short antimicrobial peptides S1 and KWWK. PMID:26033727

  3. Comparative evaluation of antimicrobials for textile applications.

    PubMed

    Windler, Lena; Height, Murray; Nowack, Bernd

    2013-03-01

    Many antimicrobial technologies are available for textiles. They may be used in many different textile applications to prevent the growth of microorganisms. Due to the biological activity of the antimicrobial compounds, the assessment of the safety of these substances is an ongoing subject of research and regulatory scrutiny. This review aims to give an overview on the main compounds used today for antimicrobial textile functionalization. Based on an evaluation of scientific publications, market data as well as regulatory documents, the potential effects of antimicrobials on the environment and on human health were considered and also life cycle perspectives were taken into account. The characteristics of each compound were summarized according to technical, environmental and human health criteria. Triclosan, silane quaternary ammonium compounds, zinc pyrithione and silver-based compounds are the main antimicrobials used in textiles. The synthetic organic compounds dominate the antimicrobials market on a weight basis. On the technical side the application rates of the antimicrobials used to functionalize a textile product are an important parameter with treatments requiring lower dosage rates offering clear benefits in terms of less active substance required to achieve the functionality. The durability of the antimicrobial treatment has a strong influence on the potential for release and subsequent environmental effects. In terms of environmental criteria, all compounds were rated similarly in effective removal in wastewater treatment processes. The extent of published information about environmental behavior for each compound varies, limiting the possibility for an in-depth comparison of all textile-relevant parameters across the antimicrobials. Nevertheless the comparative evaluation showed that each antimicrobial technology has specific risks and benefits that should be taken into account in evaluating the suitability of different antimicrobial products. The

  4. Implementation of the forward-reverse method for calculating the potential of mean force using a dynamic restraining protocol.

    PubMed

    Nategholeslam, Mostafa; Gray, C G; Tomberli, Bruno

    2014-12-11

    We present a new sampling and analysis scheme for calculating the potential of mean force (PMF) of systems studied by steered molecular dynamics simulations. This scheme, which we call the bin-passing method, is based on the forward-reverse (FR) method (due to I. Kosztin and co-workers, Kosztin et al. J. Chem. Phys. 2006, 124(6), 064106) and arguments based on the second law of thermodynamics. Applying the bin-passing method results in enhanced sampling, better separation of the reversible and irreversible work distributions, and faster convergence to the underlying PMF of the system under study. Post-simulation analysis is performed using a purpose-built software that we have made publicly available at https://github.com/1particle/bin-passing_analyzer under the terms of the GNU General Public License (version 3). Three examples are provided, for systems of varying sizes and complexities, to demonstrate the efficiency of this method and the quality of the results: for the dissociation PMF of NaCl in water, the bin-passing method obtains PMFs in excellent agreement with that obtained for the same system and using the same force-field through static (equilibrium) methods. The bin-passing method gives a very symmetric PMF for passage of a single water molecule through a DPPC bilayer, and the resultant PMF leads to permeability values in better agreement with experiments than those obtained through previous simulation studies. Finally, we consider the interaction of the antimicrobial peptide HHC-36 with two model membranes and employ the bin-passing method to obtain the PMFs for peptide adsorption to the membranes. The characteristics of these PMFs are consistent with the qualities established for the HHC-36 peptide through in vivo and in vitro experiments, as a non-toxic strong antimicrobial agent. PMID:25372312

  5. Antimicrobial peptides of multicellular organisms

    NASA Astrophysics Data System (ADS)

    Zasloff, Michael

    2002-01-01

    Multicellular organisms live, by and large, harmoniously with microbes. The cornea of the eye of an animal is almost always free of signs of infection. The insect flourishes without lymphocytes or antibodies. A plant seed germinates successfully in the midst of soil microbes. How is this accomplished? Both animals and plants possess potent, broad-spectrum antimicrobial peptides, which they use to fend off a wide range of microbes, including bacteria, fungi, viruses and protozoa. What sorts of molecules are they? How are they employed by animals in their defence? As our need for new antibiotics becomes more pressing, could we design anti-infective drugs based on the design principles these molecules teach us?

  6. Antimicrobial dihydroisocoumarins from Crassocephalum biafrae.

    PubMed

    Tabopda, Turibio K; Fotso, Gislain W; Ngoupayo, Joseph; Mitaine-Offer, Anne-Claire; Ngadjui, Bonaventure T; Lacaille-Dubois, Marie-Aleth

    2009-09-01

    Bioassay-guided fractionation of the CHCl (3)-soluble extract of the stem bark of Crassocephalum biafrae (Asteraceae) resulted in the isolation of three new dihydroisocoumarins, named biafraecoumarins A ( 1), B ( 2), and C ( 3); two known triterpenes ( 4 and 5); and a known ceramide ( 6). The structures of the new compounds were established as 7-but-15-enyl-6,8-dihydroxy-3( R)-penta-9,11-dienylisochroman-1-one ( 1), 7-butyl-6,8-dihydroxy-3( R)-penta-9,11-dienylisochroman-1-one ( 2), and 7-butyl-6,8-dihydroxy-3( R)-pent-10-enylisochroman-1-one ( 3) using spectroscopic data. Compounds 1- 3 exhibit low to significant antimicrobial activities against Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Pseudomonas picketti, Trichphyton longifusus, Aspergillus flavus, Microsporum canis, Fusarium solani, Candida albicans, and Candida glabrata. PMID:19350487

  7. Antimicrobial photodynamic therapy: An overview

    PubMed Central

    Rajesh, S.; Koshi, Elizabeth; Philip, Koshi; Mohan, Aparna

    2011-01-01

    Inflammatory periodontal disease caused by dental plaque is characterized by the clinical signs of inflammation and loss of periodontal tissue support. The mechanical removal of this biofilm and adjunctive use of antibacterial disinfectants and antibiotics have been the conventional methods of periodontal therapy. But the removal of plaque and the reduction in the number of infectious organisms can be impaired in sites with difficult access. The possibility of development of resistance to antibiotics by the target organism has led to the development of a new antimicrobial concept with fewer complications. Photodynamic therapy (PDT) involves the use of low power lasers with appropriate wavelength to kill micro organisms treated with a photosensitizer drug. PDT could be a useful adjunct to mechanical as well as antibiotics in eliminating periopathogenic bacteria. PMID:22368354

  8. Antimicrobial activity of benzylisoquinoline alkaloids.

    PubMed

    Villar, A; Mares, M; Rios, J L; Canton, E; Gobernado, M

    1987-04-01

    The antimicrobial in vitro activity of 14 benzylisoquinoline alkaloids was investigated by agar diffusion and agar dilution methods against several genera of microorganisms that included Streptococcus, Staphylococcus, Bacillus, Lysteria, Escherichia, Salmonella, Klebsiella, Pseudomonas, Enterobacter, Serratia, Shigella, Mycobacterium and Candida. Anolobine was the most active compound against grampositive bacteria with MIC90 between 12 and 50 mg/l; less active were anonaine, lysicamine and liriodenine. All the alkaloids of the noraporphine and oxoaporphine groups, with the exception of isopiline, showed activity against Mycobacterium phlei (MIC 6-25 mg/l). Candida albicans ATCC26555 was inhibited by anonaine, nornantenine and xylopine (MIC 3-12 mg/l). None of the alkaloids tested had a significant activity against gramnegative rods. The action against susceptible microorganisms was bactericidal. PMID:3615557

  9. Antimicrobial activities of Barringtonia acutangula.

    PubMed

    Rahman, M Mukhlesur; Polfreman, David; MacGeachan, Jodie; Gray, Alexander I

    2005-06-01

    Crude extracts and VLC fractions from the stem bark of Barringtonia acutangula (L.) Gaertn (Fam. Lecythidaceae) were screened for their antimicrobial activities against two Gram-positive bacteria, two Gram-negative bacteria and two fungi using a microdilution titre assay. Among the crude extracts, petroleum ether extract showed good activity against all test organisms. The VLC fraction PE 16 was found to be very effective against Bacillus subtilis (MIC=25 microg/ml) and Aspergillus niger (MIC=12.5 microg/ml). The activities were compared to standard antibiotics-kanamycin and fluconazole. The major compound from PE16 was identified as 12, 20(29)-lupadien-3-ol by NMR spectroscopy. PMID:16114086

  10. Antimicrobial Compounds from Drypetes staudtii.

    PubMed

    Grace, David; Khan, Madiha S; Friesen, Kenneth; Ata, Athar

    2016-07-01

    Antimicrobial-directed phytochemical investigation of the MeOH extract of Drypetes staudtii afforded two new compounds, 4,5-(methylenedioxy)-o-coumaroylputrescine (1), 4,5-(methylenedioxy)-o-coumaroyl-4'-N-methylputrescine (2), along with seven known natural products 4α-hydroxyeremophila-1,9-diene-3,8-dione (3), drypemolundein B (4), friedelan-3β-ol (5), erythrodiol (6), ursolic acid (7), p-coumaric acid (8), and β-sitosterol (9). Structures of compounds 1 - 9 were elucidated with the aid of extensive NMR and mass spectral studies. All of the isolates exhibited antibacterial activity against Gram-positive and Gram-negative bacteria with minimum inhibitory concentration (MIC) in the range of 8 - 128 μg/ml. Compounds 1 - 2 were also moderately active against Candida albicans with an MIC value of 32 μg/ml. PMID:27288642

  11. An antimicrobial stewardship program reduces antimicrobial therapy duration and hospital stay in surgical wards.

    PubMed

    Güerri-Fernández, R; Villar-García, J; Herrera-Fernández, S; Trenchs-Rodríguez, M; Fernández-Morato, J; Moro, L; Sancho, J; Grande, L; Clará, A; Grau, S; Horcajada, J P

    2016-06-01

    We report a quasi-experimental study of the implementation of an antimicrobial stewardship program in two surgical wards, with a pre-intervention period with just assessment of prescription and an intervention period with a prospective audit on antibiotic prescription model. There was a significant reduction of length of stay and the total days of antimicrobial administration. There were no differences in mortality between groups. The antimicrobial stewardship program led to the early detection of inappropriate empirical antibiotic treatment and was associated with a significant reduction in length of stay and the total duration of antimicrobial therapy. PMID:27167764

  12. Antimicrobial Peptides in Human Sepsis.

    PubMed

    Martin, Lukas; van Meegern, Anne; Doemming, Sabine; Schuerholz, Tobias

    2015-01-01

    Nearly 100 years ago, antimicrobial peptides (AMPs) were identified as an important part of innate immunity. They exist in species from bacteria to mammals and can be isolated in body fluids and on surfaces constitutively or induced by inflammation. Defensins have anti-bacterial effects against Gram-positive and Gram-negative bacteria as well as anti-viral and anti-yeast effects. Human neutrophil peptides (HNP) 1-3 and human beta-defensins (HBDs) 1-3 are some of the most important defensins in humans. Recent studies have demonstrated higher levels of HNP 1-3 and HBD-2 in sepsis. The bactericidal/permeability-increasing protein (BPI) attenuates local inflammatory response and decreases systemic toxicity of endotoxins. Moreover, BPI might reflect the severity of organ dysfunction in sepsis. Elevated plasma lactoferrin is detected in patients with organ failure. HNP 1-3, lactoferrin, BPI, and heparin-binding protein are increased in sepsis. Human lactoferrin peptide 1-11 (hLF 1-11) possesses antimicrobial activity and modulates inflammation. The recombinant form of lactoferrin [talactoferrin alpha (TLF)] has been shown to decrease mortality in critically ill patients. A phase II/III study with TLF in sepsis did not confirm this result. The growing number of multiresistant bacteria is an ongoing problem in sepsis therapy. Furthermore, antibiotics are known to promote the liberation of pro-inflammatory cell components and thus augment the severity of sepsis. Compared to antibiotics, AMPs kill bacteria but also neutralize pathogenic factors such as lipopolysaccharide. The obstacle to applying naturally occurring AMPs is their high nephro- and neurotoxicity. Therefore, the challenge is to develop peptides to treat septic patients effectively without causing harm. This overview focuses on natural and synthetic AMPs in human and experimental sepsis and their potential to provide significant improvements in the treatment of critically ill with severe infections. PMID

  13. Antimicrobial Peptides in Human Sepsis

    PubMed Central

    Martin, Lukas; van Meegern, Anne; Doemming, Sabine; Schuerholz, Tobias

    2015-01-01

    Nearly 100 years ago, antimicrobial peptides (AMPs) were identified as an important part of innate immunity. They exist in species from bacteria to mammals and can be isolated in body fluids and on surfaces constitutively or induced by inflammation. Defensins have anti-bacterial effects against Gram-positive and Gram-negative bacteria as well as anti-viral and anti-yeast effects. Human neutrophil peptides (HNP) 1–3 and human beta-defensins (HBDs) 1–3 are some of the most important defensins in humans. Recent studies have demonstrated higher levels of HNP 1–3 and HBD-2 in sepsis. The bactericidal/permeability-increasing protein (BPI) attenuates local inflammatory response and decreases systemic toxicity of endotoxins. Moreover, BPI might reflect the severity of organ dysfunction in sepsis. Elevated plasma lactoferrin is detected in patients with organ failure. HNP 1–3, lactoferrin, BPI, and heparin-binding protein are increased in sepsis. Human lactoferrin peptide 1–11 (hLF 1–11) possesses antimicrobial activity and modulates inflammation. The recombinant form of lactoferrin [talactoferrin alpha (TLF)] has been shown to decrease mortality in critically ill patients. A phase II/III study with TLF in sepsis did not confirm this result. The growing number of multiresistant bacteria is an ongoing problem in sepsis therapy. Furthermore, antibiotics are known to promote the liberation of pro-inflammatory cell components and thus augment the severity of sepsis. Compared to antibiotics, AMPs kill bacteria but also neutralize pathogenic factors such as lipopolysaccharide. The obstacle to applying naturally occurring AMPs is their high nephro- and neurotoxicity. Therefore, the challenge is to develop peptides to treat septic patients effectively without causing harm. This overview focuses on natural and synthetic AMPs in human and experimental sepsis and their potential to provide significant improvements in the treatment of critically ill with severe infections

  14. Optimizing antimicrobial therapy in children.

    PubMed

    Long, Sarah S

    2016-07-01

    Management of common infections and optimal use of antimicrobial agents are presented, highlighting new evidence from the medical literature that enlightens practice. Primary therapy of staphylococcal skin abscesses is drainage. Patients who have a large abscess (>5 cm), cellulitis or mixed abscess-cellulitis likely would benefit from additional antibiotic therapy. When choosing an antibiotic for outpatient management, the patient, pathogen and in vitro drug susceptibility as well as tolerability, bioavailability and safety characteristics of antibiotics should be considered. Management of recurrent staphylococcal skin and soft tissue infections is vexing. Focus is best placed on reducing density of the organism on the patient's skin and in the environment, and optimizing a healthy skin barrier. With attention to adherence and optimal dosing, acute uncomplicated osteomyelitis can be managed with early transition from parenteral to oral therapy and with a 3-4 week total course of therapy. Doxycycline should be prescribed when indicated for a child of any age. Its use is not associated with dental staining. Azithromycin should be prescribed for infants when indicated, whilst being alert to an associated ≥2-fold excess risk of pyloric stenosis with use under 6 weeks of age. Beyond the neonatal period, acyclovir is more safely dosed by body surface area (not to exceed 500 mg/m(2)/dose) than by weight. In addition to the concern of antimicrobial resistance, unnecessary use of antibiotics should be avoided because of potential later metabolic effects, thought to be due to perturbation of the host's microbiome. PMID:27263076

  15. Mechanical Analysis of an SM 2 Blk IV restrained firing within a concentric canister launcher test unit

    SciTech Connect

    Kassner, M C; Kennedy, T C; Puttapitukporn, T; Rosen, R S

    1999-03-01

    The Office of Naval Research (ONR) and PMS512 have undertaken a program to develop a new Vertical Launching System (VLS) for future generation ships, such as the DD-21 Destroyer. The Naval Sea Systems Command Combat Weapons Program (NAVSEA 05K) and Naval Surface Warfare Center Dahlgren Division (NSWCDD) are working jointly with industry and universities to develop one such launcher design, the Concentric Canister Launcher (CCL). The basic CCL design consists of a tube made of two concentric cylinders; one end is open, the other is sealed with a hemispherical end cap. During firing, the missile exhaust gas is turned 180 degrees by the hemispherical end cap and flows through the annular space between inner and outer cylinders. Depending on the missile utilized and the particular service environment of the CCL, maximum temperatures within the cylinder material have been calculated to exceed 2000 F. In an earlier study [1], the authors determined the high temperature mechanical properties of several candidate alloys being considered for fabrication of the CCL. This study [1] found that, of these candidate materials, titanium alloys exhibit higher yield stresses than that of 316L stainless steel at temperatures up to about 1000 F; above 1500 F, the yield stress of 316L stainless steel is comparable to those of the titanium alloys. The 316L stainless steel was found to strain harden (increase its flow stress with increasing strain) at temperatures up to about 1800 F. The ability of the 316L stainless steel to strain harden at high temperatures may provide an added margin of safety for engineering design of the CCL. The objective of the current study was to perform a computer simulation of the structural response of a CCL during a restrained firing, one in which a SM-2 Blk IV missile would fail to exit the canister. A finite element model of the inner cylinder, outer cylinder, end rings (mounting brackets), and lateral restraints in the uptake was constructed. An elastic

  16. Antimicrobial silver: an unprecedented anion effect.

    PubMed

    Swathy, J R; Sankar, M Udhaya; Chaudhary, Amrita; Aigal, Sahaja; Anshup; Pradeep, T

    2014-01-01

    Silver is an indispensable metal but its use has to be minimised for sustainable growth. Much of the silver lost during use is unrecoverable; an example being its use as an antimicrobial agent, a property known since ages. While developing methods to create an affordable drinking water purifier especially for the developing world, we discovered that 50 parts per billion (ppb) of Ag(+) released continuously from silver nanoparticles confined in nanoscale cages is enough to cause antimicrobial activity in conditions of normal water. Here we show that the antibacterial and antiviral activities of Ag(+) can be enhanced ~1,000 fold, selectively, in presence of carbonate ions whose concentration was maintained below the drinking water norms. The protective layers of the organisms were affected during the carbonate-assisted antimicrobial activity. It is estimated that ~1,300 tons of silver can be saved annually using this new way to enhance its antimicrobial activity. PMID:25418185

  17. Antimicrobial susceptibility pattern of Helicobacter suis strains.

    PubMed

    Vermoote, Miet; Pasmans, Frank; Flahou, Bram; Van Deun, Kim; Ducatelle, Richard; Haesebrouck, Freddy

    2011-12-15

    Helicobacter suis is a very fastidious porcine gastric pathogen, which is also considered to be of zoonotic importance. In vitro antimicrobial susceptibility cannot be determined using standard assays, as this agent only grows in a biphasic medium with an acidic pH. Therefore, a combined agar and broth dilution method was used to analyse the activity of nine antimicrobial agents against nine H. suis isolates. After 48 h microaerobic incubation, minimal inhibitory concentrations (MICs) were determined by software-assisted calculation of bacterial growth. Only for enrofloxacin a bimodal distribution of MICs was demonstrated, indicating acquired resistance in one strain, which showed an AGT→AGG (Ser→Arg) substitution at codon 99 of gyrA. In conclusion, the assay developed here is suitable for determination of the antimicrobial susceptibility of H. suis isolates, although activity of acid sensitive antimicrobial agents may be higher than predicted from MIC endpoints. PMID:21733643

  18. Antimicrobial-Coated Granules for Disinfecting Water

    NASA Technical Reports Server (NTRS)

    Akse, James R.; Holtsnider, John T.; Kliestik, Helen

    2011-01-01

    Methods of preparing antimicrobialcoated granules for disinfecting flowing potable water have been developed. Like the methods reported in the immediately preceding article, these methods involve chemical preparation of substrate surfaces (in this case, the surfaces of granules) to enable attachment of antimicrobial molecules to the surfaces via covalent bonds. A variety of granular materials have been coated with a variety of antimicrobial agents that include antibiotics, bacteriocins, enzymes, bactericides, and fungicides. When employed in packed beds in flowing water, these antimicrobial-coated granules have been proven effective against gram-positive bacteria, gram-negative bacteria, fungi, and viruses. Composite beds, consisting of multiple layers containing different granular antimicrobial media, have proven particularly effective against a broad spectrum of microorganisms. These media have also proven effective in enhancing or potentiating the biocidal effects of in-line iodinated resins and of very low levels of dissolved elemental iodine.

  19. Antimicrobial silver: An unprecedented anion effect

    PubMed Central

    Swathy, J. R.; Sankar, M. Udhaya; Chaudhary, Amrita; Aigal, Sahaja; Anshup; Pradeep, T.

    2014-01-01

    Silver is an indispensable metal but its use has to be minimised for sustainable growth. Much of the silver lost during use is unrecoverable; an example being its use as an antimicrobial agent, a property known since ages. While developing methods to create an affordable drinking water purifier especially for the developing world, we discovered that 50 parts per billion (ppb) of Ag+ released continuously from silver nanoparticles confined in nanoscale cages is enough to cause antimicrobial activity in conditions of normal water. Here we show that the antibacterial and antiviral activities of Ag+ can be enhanced ~1,000 fold, selectively, in presence of carbonate ions whose concentration was maintained below the drinking water norms. The protective layers of the organisms were affected during the carbonate-assisted antimicrobial activity. It is estimated that ~1,300 tons of silver can be saved annually using this new way to enhance its antimicrobial activity. PMID:25418185

  20. Membrane disruption mechanism of antimicrobial peptides

    NASA Astrophysics Data System (ADS)

    Lee, Ka Yee

    2012-04-01

    Largely distributed among living organisms, antimicrobial peptides are a class of small (<100 residues) host defense peptides that induce selective membrane lytic activity against microbial pathogens. The permeabilizing behavior of these diverse peptides has been commonly attributed to the formation of pores, and such pore formation has been categorized as barrel-stave, toroidal, or carpet-like. With the continuing discovery of new peptide species, many are uncharacterized and the exact mechanism is unknown. Through the use of atomic force microscopy, the disruption of supported lipid bilayer patches by protegrin-1 is concentration-dependent. The intercalation of antimicrobial peptide into the bilayer results in structures beyond that of pore formation, but with the formation of worm-like micelles at high peptide concentration. Our results suggest that antimicrobial peptide acts to lower the interfacial energy of the bilayer in a way similar to detergents. Antimicrobial peptides with structural differences, magainin-1 and aurein 1.1, exhibit a mechanistic commonality.

  1. Antimicrobial dispensing by Ontario dairy veterinarians

    PubMed Central

    Léger, David F.; Newby, Nathalie C.; Reid-Smith, Richard; Anderson, Neil; Pearl, David L.; Lissemore, Kerry D.; Kelton, David F.

    2015-01-01

    This questionnaire-based cross-sectional study was designed to capture the demographics of dairy practitioners in Ontario and to describe aspects of antimicrobial dispensing on-farm and over-the-counter by these veterinarians. The information collected revealed that the prescription status of a drug and the level of veterinary-client-patient relationship were important elements of dispensing policies. Over-the-counter dispensing records were incomplete, while only a small proportion of on-farm dispensing records contained pertinent information and directions as required by the Veterinarians Act. While respondents recognized that antimicrobial use in dairy herds could lead to resistance in cattle, few indicated that this was a significant public health issue. Veterinarians can play a key role in antimicrobial stewardship, part of which is the provision of complete written dispensing instructions to producers for antimicrobial use in dairy cattle. PMID:26130834

  2. Photodynamic antimicrobial activity of hypocrellin A.

    PubMed

    Su, Yujie; Sun, Jun; Rao, Shengqi; Cai, Yujie; Yang, Yanjun

    2011-04-01

    Antimicrobial photodynamic therapy is a recently developed therapeutic option that combines a non-toxic photosensitizer with harmless visible light to damage the microbial cell. Hypocrellin A (HA), a natural occurring lipid-soluble perylenequinone pigment, has gained considerable interest since its anticancer and antiviral activities have been reported. Here, we examined the antimicrobial activity of HA against Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative bacteria (Escherichia coli, Salmonella typhimurium). The results indicate that HA has a photodynamic antimicrobial activity against both Gram-positive and Gram-negative bacteria when CaCl(2) or MgCl(2) was employed. A loose binding has been established between HA and the organisms. Molecular oxygen is significantly involved in the photodynamic action of HA. Furthermore, HA maintains a photodynamic activity in terms of both types I and II reactions. Our results confirm the potential of HA to be used as a photosensitizer in antimicrobial photodynamic therapy. PMID:21300554

  3. The First Salamander Defensin Antimicrobial Peptide

    PubMed Central

    Jiang, Ke; Rong, Mingqiang; Lai, Ren

    2013-01-01

    Antimicrobial peptides have been widely identified from amphibian skins except salamanders. A novel antimicrobial peptide (CFBD) was isolated and characterized from skin secretions of the salamander, Cynops fudingensis. The cDNA encoding CFBD precursor was cloned from the skin cDNA library of C. fudingensis. The precursor was composed of three domains: signal peptide of 17 residues, mature peptide of 41 residues and intervening propeptide of 3 residues. There are six cysteines in the sequence of mature CFBD peptide, which possibly form three disulfide-bridges. CFBD showed antimicrobial activities against Staphylococcus aureus, Bacillus subtilis, Candida albicans and Escherichia coli. This peptide could be classified into family of β-defensin based on its seqeuence similarity with β-defensins from other vertebrates. Evolution analysis indicated that CFBD was close to fish β-defensin. As far as we know, CFBD is the first β-defensin antimicrobial peptide from salamanders. PMID:24386139

  4. Towards Self-regenerating Antimicrobial Polymer Surfaces

    PubMed Central

    Dorner, Franziska; Boschert, David; Schneider, Alexandra; Hartleb, Wibke; Al-Ahmad, Ali; Lienkamp, Karen

    2016-01-01

    Regeneration of functional polymer surfaces after damage or contamination is an unresolved scientific challenge, and also of practical importance. In this proof-of-concept study, we present a method to regenerate a functional surface property using a polymer multi-layer architecture. This is exemplified using antimicrobially active surfaces. The idea is to shed the top layer of the polymer layer stack, like a reptile shedding its skin. The proof-of-concept stack consists of two antimicrobial layers and a degradable interlayer. Shedding of the top layer is enabled by degrading that interlayer. The shedding process was analyzed by quantitative fluorescence microscopy, ellipsometry, and FTIR spectroscopy. Antimicrobial assays revealed that the functionality of the emerging antimicrobial layer was fully retained after shedding. PMID:27489747

  5. Emergency department antimicrobial considerations in severe sepsis.

    PubMed

    Green, Robert S; Gorman, Sean K

    2014-11-01

    Severe sepsis and septic shock are common problems in the emergency department patient population and require expert clinical skill by members of the emergency department team to maximize optimal patient outcomes. Although various guidelines have been developed for the management of these patients, issues around antimicrobial-related considerations in critically ill patients require further evidence-based attention. In this review article, important factors related to patient illness, microorganism, timing of antimicrobial administration, and source control are discussed. PMID:25441038

  6. Antimicrobial benzopyrans from the receptacle of sunflower.

    PubMed

    Satoh, A; Utamura, H; Ishizuka, M; Endo, N; Tsuji, M; Nishimura, H

    1996-04-01

    The antimicrobial substances in sunflower (Helianthus annuus) were investigated. Two antifungal benzopyran derivatives, 6-acetyl-2,2-dimethyl-1,2-benzopyran (1) and 6-acetyl-7-hydroxy-2,2-dimethyl-1,2-benzopyran (2), were isolated from the ethanol extract of sunflower receptacles. The antimicrobial activities of isolated compounds 1 and 2 and their related compounds (precocenes) were evaluated by the paper disk method, using Pyricularia oryzae as the test fungus. PMID:8829537

  7. Antimicrobial prophylaxis in caesarean section delivery

    PubMed Central

    Liu, Ronghua; Lin, Lin; Wang, Dujuan

    2016-01-01

    Antimicrobial prophylaxis is used routinely for pre-, intra- and post-operative caesarean section. One of the most important risk factors for postpartum infection is caesarean delivery. Caesarean section shows a higher incidence of infection than vaginal delivery. It is complicated by surgical site infections, endometritis or urinary tract infection. The aim of the present study was to assess the usage of antimicrobials in women undergoing caesarean section at a Tertiary Care Hospital. A prospective study was conducted in 100 women during the period of February 2013 to August 2013 in the inpatient Department of Gynaecology and Obstetrics. Data collected included the age of the patient, gravidity, and type of caesarean section, which was analyzed for the nature and number of antimicrobials prescribed, duration of treatment, polypharmacy, fixed-dose combinations, generic/brand names used and failure of prophylaxis. Antimicrobial prophylaxis was administered to the patients. The most commonly prescribed antimicrobial was a combination of ceftriaxone and sulbactam. Of 100 patients, 87% were aged 20–35 years. The highest proportion of patients were primigravida 72%. Elective procedure was carried out in 38%, the remaining were emergency C-section in whom intra- and post-operative antimicrobial prophylaxis was given for a duration of 7 days. In total, 27% of patients were reported with infection even after the antimicrobial prophylaxis. In conclusion, pre-operative prophylaxis was given in the early rupture of membranes. Fixed-dose combinations were preferred. Incidence of infection even after antimicrobial prophylaxis was reported due to pre-existing infection, debilitating disease or prolonged rupture of membranes. Patients with recurrent infection were shifted to amoxicillin and clavulinic acid combination. Drugs were prescribed only by brand names which is of concern. PMID:27446303

  8. Optimizing antimicrobial therapy in critically ill patients.

    PubMed

    Vitrat, Virginie; Hautefeuille, Serge; Janssen, Cécile; Bougon, David; Sirodot, Michel; Pagani, Leonardo

    2014-01-01

    Critically ill patients with infection in the intensive care unit (ICU) would certainly benefit from timely bacterial identification and effective antimicrobial treatment. Diagnostic techniques have clearly improved in the last years and allow earlier identification of bacterial strains in some cases, but these techniques are still quite expensive and not readily available in all institutions. Moreover, the ever increasing rates of resistance to antimicrobials, especially in Gram-negative pathogens, are threatening the outcome for such patients because of the lack of effective medical treatment; ICU physicians are therefore resorting to combination therapies to overcome resistance, with the direct consequence of promoting further resistance. A more appropriate use of available antimicrobials in the ICU should be pursued, and adjustments in doses and dosing through pharmacokinetics and pharmacodynamics have recently shown promising results in improving outcomes and reducing antimicrobial resistance. The aim of multidisciplinary antimicrobial stewardship programs is to improve antimicrobial prescription, and in this review we analyze the available experiences of such programs carried out in ICUs, with emphasis on results, challenges, and pitfalls. Any effective intervention aimed at improving antibiotic usage in ICUs must be brought about at the present time; otherwise, we will face the challenge of intractable infections in critically ill patients in the near future. PMID:25349478

  9. Optimizing antimicrobial therapy in critically ill patients

    PubMed Central

    Vitrat, Virginie; Hautefeuille, Serge; Janssen, Cécile; Bougon, David; Sirodot, Michel; Pagani, Leonardo

    2014-01-01

    Critically ill patients with infection in the intensive care unit (ICU) would certainly benefit from timely bacterial identification and effective antimicrobial treatment. Diagnostic techniques have clearly improved in the last years and allow earlier identification of bacterial strains in some cases, but these techniques are still quite expensive and not readily available in all institutions. Moreover, the ever increasing rates of resistance to antimicrobials, especially in Gram-negative pathogens, are threatening the outcome for such patients because of the lack of effective medical treatment; ICU physicians are therefore resorting to combination therapies to overcome resistance, with the direct consequence of promoting further resistance. A more appropriate use of available antimicrobials in the ICU should be pursued, and adjustments in doses and dosing through pharmacokinetics and pharmacodynamics have recently shown promising results in improving outcomes and reducing antimicrobial resistance. The aim of multidisciplinary antimicrobial stewardship programs is to improve antimicrobial prescription, and in this review we analyze the available experiences of such programs carried out in ICUs, with emphasis on results, challenges, and pitfalls. Any effective intervention aimed at improving antibiotic usage in ICUs must be brought about at the present time; otherwise, we will face the challenge of intractable infections in critically ill patients in the near future. PMID:25349478

  10. The antimicrobial possibilities of green tea

    PubMed Central

    Reygaert, Wanda C.

    2014-01-01

    Green tea is a popular drink, especially in Asian countries, although its popularity continues to spread across the globe. The health benefits of green tea, derived from the leaves of the Camellia sinensis plant, have been studied for many years. Fairly recently, researchers have begun to look at the possibility of using green tea in antimicrobial therapy, and the potential prevention of infections. The particular properties of catechins found in the tea have shown promise for having antimicrobial effects. There are four main catechins (polyphenols) found in green tea: (-)-epicatechin (EC), (-)-epicatechin-3-gallate (ECG), (-)-epigallocatechin (EGC), and (-)-epigallocatechin-3-gallate (EGCG). Three of these, ECG, EGC, and EGCG have been shown to have antimicrobial effects against a variety of organisms. These catechins have exhibited a variety of antimicrobial mechanisms. The results of studies on the antimicrobial effects of green tea have shown that the potential for preventive and therapeutic purposes is present. Further data collection on studies performed with human consumption during the course of infections, and studies on the occurrence of infections in populations that consume regular amounts of green tea will be necessary to complete the picture of its antimicrobial possibilities. PMID:25191312

  11. Understanding the mechanisms and drivers of antimicrobial resistance.

    PubMed

    Holmes, Alison H; Moore, Luke S P; Sundsfjord, Arnfinn; Steinbakk, Martin; Regmi, Sadie; Karkey, Abhilasha; Guerin, Philippe J; Piddock, Laura J V

    2016-01-01

    To combat the threat to human health and biosecurity from antimicrobial resistance, an understanding of its mechanisms and drivers is needed. Emergence of antimicrobial resistance in microorganisms is a natural phenomenon, yet antimicrobial resistance selection has been driven by antimicrobial exposure in health care, agriculture, and the environment. Onward transmission is affected by standards of infection control, sanitation, access to clean water, access to assured quality antimicrobials and diagnostics, travel, and migration. Strategies to reduce antimicrobial resistance by removing antimicrobial selective pressure alone rely upon resistance imparting a fitness cost, an effect not always apparent. Minimising resistance should therefore be considered comprehensively, by resistance mechanism, microorganism, antimicrobial drug, host, and context; parallel to new drug discovery, broad ranging, multidisciplinary research is needed across these five levels, interlinked across the health-care, agriculture, and environment sectors. Intelligent, integrated approaches, mindful of potential unintended results, are needed to ensure sustained, worldwide access to effective antimicrobials. PMID:26603922

  12. Antimicrobial use on Canadian dairy farms.

    PubMed

    Saini, V; McClure, J T; Léger, D; Dufour, S; Sheldon, A G; Scholl, D T; Barkema, H W

    2012-03-01

    Antimicrobial use (AMU) data are critical for formulating policies for containing antimicrobial resistance. The present study determined AMU on Canadian dairy farms and characterized variation in AMU based on herd-level factors such as milk production, somatic cell count, herd size, geographic region and housing type. Drug use data were collected on 89 dairy herds in 4 regions of Canada, Alberta, Ontario, Québec, and the Maritime provinces (Prince Edward Island, New Brunswick, and Nova Scotia) for an average of 540 d per herd. Dairy producers and farm personnel were asked to deposit empty drug containers into specially provided receptacles. Antimicrobial use was measured as antimicrobial drug use rate (ADUR), with the unit being number of animal defined-daily doses (ADD)/1,000 cow-days. Antimicrobial drug use rates were determined at farm, region, and national level. Combined ADUR of all antimicrobial classes was 14.35 ADD/1,000 cow-days nationally. National level ADUR of the 6 most commonly used antimicrobial drug classes, cephalosporins, penicillins, penicillin combinations, tetracyclines, trimethoprim-sulfonamide combinations, and lincosamides were 3.05, 2.56, 2.20, 1.83, 0.87, and 0.84 ADD/1,000 cow-days, respectively. Dairy herds in Ontario were higher users of third-generation cephalosporins (ceftiofur) than in Québec. Alberta dairy herds were higher users of tetracyclines in comparison to Maritimes. Antimicrobial drug use rate was higher via systemic route as compared with intramammary and other routes of administration (topical, oral, and intrauterine). The ADUR of antimicrobials used intramammarily was higher for clinical mastitis treatment than dry cow therapy. For dry cow therapy, penicillin ADUR was greater than ADUR of first-generation cephalosporins. For clinical mastitis treatment, ADUR of intramammary penicillin combinations was greater than ADUR of cephapirin. Herd-level milk production was positively associated with overall ADUR, ADUR of

  13. Quaternized Chitosan as an Antimicrobial Agent: Antimicrobial Activity, Mechanism of Action and Biomedical Applications in Orthopedics

    PubMed Central

    Tan, Honglue; Ma, Rui; Lin, Chucheng; Liu, Ziwei; Tang, Tingting

    2013-01-01

    Chitosan (CS) is a linear polysaccharide with good biodegradability, biocompatibility and antimicrobial activity, which makes it potentially useful for biomedical applications, including an antimicrobial agent either alone or blended with other polymers. However, the poor solubility of CS in most solvents at neutral or high pH substantially limits its use. Quaternary ammonium CS, which was prepared by introducing a quaternary ammonium group on a dissociative hydroxyl group or amino group of the CS, exhibited improved water solubility and stronger antibacterial activity relative to CS over an entire range of pH values; thus, this quaternary modification increases the potential biomedical applications of CS in the field of anti-infection. This review discusses the current findings on the antimicrobial properties of quaternized CS synthesized using different methods and the mechanisms of its antimicrobial actions. The potential antimicrobial applications in the orthopedic field and perspectives regarding future studies in this field are also considered. PMID:23325051

  14. Oral administration of antimicrobials increase antimicrobial resistance in E. coli from chicken--a systematic review.

    PubMed

    Simoneit, C; Burow, E; Tenhagen, B-A; Käsbohrer, A

    2015-01-01

    Antimicrobials play an important role in animal and human health care. It was the aim of this systematic review to assess the effects of oral administration of antimicrobials on the development of antimicrobial resistance (AMR) in Escherichia coli (E. coli) from chickens. Moreover, the effects of the administration of more than one antimicrobial and of different dosages were studied. Literature was searched in November 2012 from the electronic databases ISI Web of Science, PubMed, Scopus and a national literature database (DIMDI) as well as the database ProQuest LLC. The search was updated in March 2014. Original studies describing a treatment (A) and a control group of either non-treatment (C) or initial value (0) and determining AMR in E. coli at different sample points (SP) were included. The literature search resulted in 35 full text articles on the topic, seven (20%) of which contained sufficient information on the administered antimicrobial and the impact of treatment on AMR. Most papers described the use of more than one antimicrobial, several dosages, controls (non-treatment or pre-treatment) and measured AMR at different SPs leading to a total of 227 SPs on the impact of the use of antimicrobials on AMR in chickens. 74% of the SPs (168/227) described a higher AMR-rate in E. coli from treated animals than from controls. After the administration of a single antimicrobial, AMR increased at 72% of the SPs. Administration of more than one antimicrobial increased AMR at 82% of the SPs. Higher dosages were associated with similar or higher AMR rates. The limited number of studies for each antimicrobial agent and the high variability in the resistance effect call for more well designed studies on the impact of oral administration on AMR development and spread. PMID:25433717

  15. Antimicrobial therapy of pulmonary tuberculosis*

    PubMed Central

    McDermott, Walsh

    1960-01-01

    The discovery, some nine years ago, of the highly specific antituberculous drug, isoniazid, marked an important advance in the antimicrobial therapy of tuberculosis, first practised successfully with streptomycin and p-aminosalicylic acid (PAS) in the late 'forties. Isoniazid is relatively non-toxic and, unlike streptomycin, can be administered orally, so that it is eminently suitable for use, either alone or in combination with PAS, in the domiciliary treatment of tuberculous patients. The wisdom of employing it on a large scale in home-treatment programmes, however, has been questioned on the ground that such wide-spread use might result in a spread of tubercle bacilli resistant to the drug. This controversial subject is discussed in some detail in this general review of the chemotherapy of tuberculosis. The author is convinced that, so far, the benefits of isoniazid therapy have outweighed the disadvantages and, though well aware of the possible consequences in terms of isoniazid-resistance, sees no reason at the present time for not making full use of this valuable weapon in the antituberculosis armamentarium. PMID:20604078

  16. The Endogenous Cell-Fate Factor Dachshund restrains Prostate Epithelial Cell Migration via Repression of Cytokine Secretion via a CXCL Signaling Module

    PubMed Central

    Chen, Ke; Wu, Kongming; Jiao, Xuanmao; Wang, Liping; Ju, Xiaoming; Wang, Min; Di Sante, Gabriele; Xu, Shaohua; Wang, Qiong; Li, Kevin; Sun, Xin; Xu, Congwen; Li, Zhiping; Casimiro, Mathew C.; Ertel, Adam; Addya, Sankar; McCue, Peter; Lisanti, Michael P.; Wang, Chenguang; Davis, Richard J.; Mardon, Graeme; Pestell, Richard G.

    2015-01-01

    Prostate cancer (PCa) is the second leading form of cancer death in men. In a subset of PCa patients increased chemokine signaling IL-8 and IL-6 correlates with androgen therapy-resistant prostate cancer (CRPC). IL-8 and IL-6 are produced by prostate epithelial cells and promote PCa cell invasion, however the mechanisms restraining prostate epithelial cell cytokine secretion are poorly understood. Herein the cell-fate determinant factor DACH1 inhibited androgen therapy-resistant prostate cancer (CRPC) tumor growth in mice. Using Dach1fl/fl/Probasin-Cre bi-transgenic mice, we show IL-8 and IL-6 secretion was altered ~1000 fold by endogenous Dach1. Endogenous Dach1 is shown to serve as a key endogenous restraint to prostate epithelial cell growth and restrains migration via CXCL signaling. DACH1 inhibited expression, transcription and secretion of the CXCL genes (IL-8, IL-6) by binding to their promoter regulatory regions in chromatin. DACH1 is thus a newly defined determinant of benign and malignant prostate epithelium cellular growth, migration and cytokine abundance in vivo. PMID:25769723

  17. Derivation of Reliable Geometries in QM Calculations of DNA Structures: Explicit Solvent QM/MM and Restrained Implicit Solvent QM Optimizations of G-Quadruplexes.

    PubMed

    Gkionis, Konstantinos; Kruse, Holger; Šponer, Jiří

    2016-04-12

    Modern dispersion-corrected DFT methods have made it possible to perform reliable QM studies on complete nucleic acid (NA) building blocks having hundreds of atoms. Such calculations, although still limited to investigations of potential energy surfaces, enhance the portfolio of computational methods applicable to NAs and offer considerably more accurate intrinsic descriptions of NAs than standard MM. However, in practice such calculations are hampered by the use of implicit solvent environments and truncation of the systems. Conventional QM optimizations are spoiled by spurious intramolecular interactions and severe structural deformations. Here we compare two approaches designed to suppress such artifacts: partially restrained continuum solvent QM and explicit solvent QM/MM optimizations. We report geometry relaxations of a set of diverse double-quartet guanine quadruplex (GQ) DNA stems. Both methods provide neat structures without major artifacts. However, each one also has distinct weaknesses. In restrained optimizations, all errors in the target geometries (i.e., low-resolution X-ray and NMR structures) are transferred to the optimized geometries. In QM/MM, the initial solvent configuration causes some heterogeneity in the geometries. Nevertheless, both approaches represent a decisive step forward compared to conventional optimizations. We refine earlier computations that revealed sizable differences in the relative energies of GQ stems computed with AMBER MM and QM. We also explore the dependence of the QM/MM results on the applied computational protocol. PMID:26914292

  18. Antimicrobial Characteristics of Heated Eggshell Powder.

    PubMed

    Ohshima, Yuki; Takada, Daisuke; Namai, Satoe; Sawai, Jun; Kikuchi, Mikio; Hotta, Mikinori

    2015-01-01

    Eggshells have high bioavailability and can be used as a source of calcium. The main component is CaCO3, which, when heated, is converted to CaO. Seashells are also mainly composed of CaCO3 and were previously found to exhibit antimicrobial activity after being heated. In this study, heated eggshell powder (HESP) was found to have antimicrobial activity against bacterial vegetative cells, fungi and bacterial spores. Parameters, such as the minimum inhibitory concentration, were determined with kinetic analysis using an indirect conductimetric assay. Moreover, HESP was able to kill the Bacillus subtilis spores. There were no significant differences in the activity between HESP, heated scallop-shell powder and pure CaO. The MIC values for HESP against bacteria and fungi were 0.29-0.43 and 1.3-1.5 mg/mL, respectively. Against B. subtilis spores, a reduction of two orders of magnitude of viability was confirmed following 20 min of treatment at 10 mg/mL at 60 ℃. The active oxygen generated from the HESP slurry was examined with chemiluminescence. The intensity of this increased with increasing concentrations of the HESP slurry. This suggests that HESP could be used as a natural antimicrobial agent. Although a high pH is the main contributor to this antimicrobial activity, active oxygen species generated from HESP are likely to be the main antimicrobial agents.. PMID:26699855

  19. Antimicrobial Activity of Carbon-Based Nanoparticles

    PubMed Central

    Maleki Dizaj, Solmaz; Mennati, Afsaneh; Jafari, Samira; Khezri, Khadejeh; Adibkia, Khosro

    2015-01-01

    Due to the vast and inappropriate use of the antibiotics, microorganisms have begun to develop resistance to the commonly used antimicrobial agents. So therefore, development of the new and effective antimicrobial agents seems to be necessary. According to some recent reports, carbon-based nanomaterials such as fullerenes, carbon nanotubes (CNTs) (especially single-walled carbon nanotubes (SWCNTs)) and graphene oxide (GO) nanoparticles show potent antimicrobial properties. In present review, we have briefly summarized the antimicrobial activity of carbon-based nanoparticles together with their mechanism of action. Reviewed literature show that the size of carbon nanoparticles plays an important role in the inactivation of the microorganisms. As major mechanism, direct contact of microorganisms with carbon nanostructures seriously affects their cellular membrane integrity, metabolic processes and morphology. The antimicrobial activity of carbon-based nanostructures may interestingly be investigated in the near future owing to their high surface/volume ratio, large inner volume and other unique chemical and physical properties. In addition, application of functionalized carbon nanomaterials as carriers for the ordinary antibiotics possibly will decrease the associated resistance, enhance their bioavailability and provide their targeted delivery. PMID:25789215

  20. Health and economic impacts of antimicrobial resistance.

    PubMed

    Holmberg, S D; Solomon, S L; Blake, P A

    1987-01-01

    For comparison of the impacts of infections due to antimicrobial-resistant bacteria with those of infections due to antimicrobial-susceptible strains of the same bacteria, data were evaluated from 175 published and unpublished reports of investigations of nosocomial and community-acquired infections with selected bacteria. The evaluation of outcomes of hospital-acquired infections with resistant organisms was often confounded by risk factors also associated with poor outcomes. Nevertheless, for both nosocomial and community-acquired infections, the mortality, the likelihood of hospitalization, and the length of hospital stay were usually at least twice as great for patients infected with drug-resistant strains as for those infected with drug-susceptible strains of the same bacteria. Poor outcomes could be attributed both to the expected effects of ineffective antimicrobial therapy and to the unexpected occurrence of drug-resistant infections complicated by prior antimicrobial therapy for other medical problems. Although the adverse economic and health effects of drug-resistant bacterial infections can only be roughly quantified, it is concluded that antimicrobial resistance is an important health problem and an economic burden to society. PMID:3321356

  1. An institutional review of antimicrobial stewardship interventions.

    PubMed

    Cao, Henry; Phe, Kady; Laine, Gregory A; Russo, Hannah R; Putney, Kimberly S; Tam, Vincent H

    2016-09-01

    In order to combat increasing rates of bacterial resistance, many institutions have implemented antimicrobial stewardship programmes (ASPs) to improve antibiotic use. To ascertain the potential impact of our stewardship programme at Baylor St Luke's Medical Center (Houston, TX), antimicrobial-related interventions were analysed over a 4-year period. ASP recommendations related to antimicrobial therapy from 2009 to 2012 were retrieved from the hospital electronic database and were retrospectively reviewed. The number of interventions for each time period was adjusted to the hospital census data. The interventions were randomly assessed and categorised for clinical significance based on established institutional guidelines. In total, 14654 non-duplicate antimicrobial therapy interventions were retrieved, of which 11874 (81.0%) were audited for accuracy. Approximately 13 interventions were made per 1000 patient-days, but there were no significant patterns observed regarding the number of interventions performed from month to month (range 8-21). The most frequent types of interventions were related to inappropriate dosing (39.0%), antimicrobial selection (20.5%) and drug allergy (13.0%). Serious adverse drug events (ADEs) were potentially avoided in 20.7% of all interventions. Cumulative potential cost avoidance was more than US$6.5 million. In our institution, proper drug and dose selection were the major components of the ASP. Without focusing solely on reduction of drug acquisition costs, implementation of an ASP could still be cost effective by improving the quality of patient care and avoiding ADEs with serious consequences. PMID:27530844

  2. Antimicrobial Cyclic Peptides for Plant Disease Control

    PubMed Central

    Lee, Dong Wan; Kim, Beom Seok

    2015-01-01

    Antimicrobial cyclic peptides derived from microbes bind stably with target sites, have a tolerance to hydrolysis by proteases, and a favorable degradability under field conditions, which make them an attractive proposition for use as agricultural fungicides. Antimicrobial cyclic peptides are classified according to the types of bonds within the ring structure; homodetic, heterodetic, and complex cyclic peptides, which in turn reflect diverse physicochemical features. Most antimicrobial cyclic peptides affect the integrity of the cell envelope. This is achieved through direct interaction with the cell membrane or disturbance of the cell wall and membrane component biosynthesis such as chitin, glucan, and sphingolipid. These are specific and selective targets providing reliable activity and safety for non-target organisms. Synthetic cyclic peptides produced through combinatorial chemistry offer an alternative approach to develop antimicrobials for agricultural uses. Those synthesized so far have been studied for antibacterial activity, however, the recent advancements in powerful technologies now promise to provide novel antimicrobial cyclic peptides that are yet to be discovered from natural resources. PMID:25774105

  3. Biopolymer-based antimicrobial packaging: a review.

    PubMed

    Cha, Dong Su; Chinnan, Manjeet S

    2004-01-01

    The term antimicrobialpackaging encompasses any packaging technique(s) used to control microbial growth in a food product. These include packaging materials and edible films and coatings that contain antimicrobial agents and also techniques that modify the atmosphere within the package. In recent years, antimicrobial packaging has attracted much attention from the food industry because of the increase in consumer demand for minimally processed, preservative-free products. Reflecting this demand, the preservative agents must be applied to packaging in such away that only low levels of preservatives come into contact with the food. The film or coating technique is considered to be more effective, although more complicated to apply. New antimicrobial packaging materials are continually being developed. Many of them exploit natural agents to control common food-borne microorganisms. Current trends suggest that, in due course, packaging will generally incorporate antimicrobial agents, and the sealing systems will continue to improve. The focus of packaging in the past has been on the appearance, size, and integrity of the package. A greater emphasis on safety features associated with the addition of antimicrobial agents is perhaps the next area for development in packaging technology. PMID:15462127

  4. Development and construction of low-cracking high-performance concrete (LC-HPC) bridge decks: Free shrinkage tests, restrained ring tests, construction experience, and crack survey results

    NASA Astrophysics Data System (ADS)

    Yuan, Jiqiu

    2011-12-01

    The development, construction, and evaluation of low-cracking high-performance concrete (LC-HPC) bridge decks are described based on laboratory test results and experiences gained during the construction of 13 LC-HPC bridge decks in Kansas, along with another deck bid under the LC-HPC specifications but for which the owner did not enforce the specification. This study is divided into four parts covering (1) an evaluation of the free shrinkage properties of LC-HPC candidate mixtures, (2) an investigation of the relationship between the evaporable water content in the cement paste and the free shrinkage of concrete, (3) a study of the restrained shrinkage performance of concrete using restrained ring tests, and (4) a description of the construction and preliminary evaluation of LC-HPC and control bridge decks constructed in Kansas. The first portion of the study involves evaluating the effects of the duration of curing, fly ash, and a shrinkage reducing admixture (SRA) on the free-shrinkage characteristics of concrete mixtures. The results indicate that an increase of curing period reduces free shrinkage. With 7 days of curing, concretes containing fly ash as a partial replacement for cement exhibit higher free shrinkage than concretes with 100% portland cement. When the curing period is increased to 14, 28, and 56 days, the adverse effect of adding fly ash on free shrinkage is minimized and finally reversed. The addition of an SRA significantly reduces free shrinkage for both the 100% portland cement mixture and the mixture containing fly ash. The second portion of the study investigates the relationship between the evaporable water content in the cement paste and the free shrinkage of concrete. A linear relationship between free shrinkage and evaporable water content in the cement paste is observed. For a given mixture, specimens cured for a longer period contain less evaporable water and exhibit lower free shrinkage and less weight loss in the free shrinkage

  5. Antimicrobial Resistance in Salmonella Isolates Recovered from Cattle at Slaughter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Since 1997, the animal arm of the National Antimicrobial Resistance Monitoring System (NARMS) has monitored changes in antimicrobial susceptibilities of Salmonella isolates from animal origin. Additionally, since 2000, susceptibility of bovine Salmonella isolates collected in the US has ...

  6. Clinical implications of antimicrobial resistance: how big is the problem?

    PubMed

    Duckworth, Georgia

    2002-03-01

    This presentation addresses the question of the size of the antimicrobial resistance problem by examining the monitoring of antimicrobial use and resistance. It focuses on the main sources of information, possible pitfalls of the data and the susceptibility of the main pathogens responsible for bacteraemias in England and Wales. It addresses some of the difficulties in establishing the link between antimicrobial resistance and antimicrobial prescribing and concludes with some thoughts on necessary developments. PMID:12044283

  7. Antimicrobials: classifications and uses in critical care.

    PubMed

    Cisneros-Farrar, Francisca; Parsons, Lynn C

    2007-03-01

    Patients in the critical care setting are at high risk for infection because their normal host defenses are compromised. Critical care patients frequently have complicated, multisystem, mixed infections that can be life threatening. Optimal patient outcomes are the result of (1) early identification of signs and symptoms of infection; (2) nursing knowledge about common antimicrobials and their side effects and adverse reactions; (3) obtaining cultures before starting empiric therapy with antimicrobials; (4) consulting as needed with the infection control team; (5) practicing basic measures of infection control, such as hand washing; and (6) using special isolation precautions when the patient's condition warrants special care. The nurse also needs to be vigilant to the signs of toxicity from antimicrobial therapy. These interventions can save the critical care patient's life, prevent others from becoming infected, and save the hospital precious fiscal resources. PMID:17338949

  8. Mechanisms of Antimicrobial Resistance in ESKAPE Pathogens

    PubMed Central

    Santajit, Sirijan; Indrawattana, Nitaya

    2016-01-01

    The ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) are the leading cause of nosocomial infections throughout the world. Most of them are multidrug resistant isolates, which is one of the greatest challenges in clinical practice. Multidrug resistance is amongst the top three threats to global public health and is usually caused by excessive drug usage or prescription, inappropriate use of antimicrobials, and substandard pharmaceuticals. Understanding the resistance mechanisms of these bacteria is crucial for the development of novel antimicrobial agents or other alternative tools to combat these public health challenges. Greater mechanistic understanding would also aid in the prediction of underlying or even unknown mechanisms of resistance, which could be applied to other emerging multidrug resistant pathogens. In this review, we summarize the known antimicrobial resistance mechanisms of ESKAPE pathogens. PMID:27274985

  9. Bacterial strategies of resistance to antimicrobial peptides.

    PubMed

    Joo, Hwang-Soo; Fu, Chih-Iung; Otto, Michael

    2016-05-26

    Antimicrobial peptides (AMPs) are a key component of the host's innate immune system, targeting invasive and colonizing bacteria. For successful survival and colonization of the host, bacteria have a series of mechanisms to interfere with AMP activity, and AMP resistance is intimately connected with the virulence potential of bacterial pathogens. In particular, because AMPs are considered as potential novel antimicrobial drugs, it is vital to understand bacterial AMP resistance mechanisms. This review gives a comparative overview of Gram-positive and Gram-negative bacterial strategies of resistance to various AMPs, such as repulsion or sequestration by bacterial surface structures, alteration of membrane charge or fluidity, degradation and removal by efflux pumps.This article is part of the themed issue 'Evolutionary ecology of arthropod antimicrobial peptides'. PMID:27160595

  10. Prospective approach to managing antimicrobial drug shortages.

    PubMed

    Griffith, Milena M; Patel, Jean A; Sutton, Sarah H; Bolon, Maureen K; Esterly, John S; Gross, Alan E; Postelnick, Michael J; Zembower, Teresa R; Scheetz, Marc H

    2012-07-01

    Antimicrobial drug shortages continue to increase, with few new therapeutic options available. Nationally, proposals have been offered to alleviate drug shortages; however, these recommendations are unlikely to effect change in the near future. Thus, antimicrobial stewardship leaders in acute care hospitals must develop a prospective management strategy to lessen the impact of these shortages on patient care. Herein, we describe several resources available to aid professionals in antimicrobial stewardship and healthcare epidemiology to manage drug shortages. An effective approach should include prospectively tracking shortages and maximizing inventory by appropriately managing usage. Several tenets should underpin this management. Alternative agents should be rationally chosen before the inventory of the primary agent has reached zero, ethical considerations should be taken into account, and timely notification and communication with key stakeholders should occur throughout the prescribing and dispensing process. PMID:22669238

  11. The Antimicrobial Activity of Porphyrin Attached Polymers

    NASA Astrophysics Data System (ADS)

    Thompson, Lesley

    2008-03-01

    We are interested in testing the antimicrobial activity of a porphyrin that is attached to a polymer. The porphyrin (5-(4-carboxyphenyl)-10,15,20-tris-(4-pryridyl)) was synthesized from methyl 4-formyl benzoate, 4-pyridinecarboxaldehyde, and pyrrole and attached to a copolymer of polystyrene/poly(vinyl benzyl chloride), which was synthesized by free radical polymerization. The antimicrobial activity of the polymer-attached porphyrin was then determined for gram-negative E. Coli grown to 0.80 OD. In this procedure, glass slides were coated with polymer-attached porphyrin via dip-coating, and the E. Coli bacteria were plated in Luria Broth media. The plates were subsequently exposed to light overnight before they were incubated as porphyrins act as photo-sensitizers when irradiated with light. The polymer-attached porphyrin did exhibit antimicrobial activity and parameters that affect its efficiency will be discussed.

  12. Antimicrobial use and stewardship programs among dialysis centers.

    PubMed

    D'Agata, Erika M C

    2013-01-01

    Antimicrobial exposure contributes to the emergence and spread of multidrug-resistant organisms. As rates of colonization and infection with these organisms are among the highest in the population of chronic hemodialysis patients and antimicrobial exposure among this patient population is extensive, it is imperative to prescribe antimicrobials judiciously. Thirty to forty percent of chronic hemodialysis patients receive at least one dose of antimicrobials in outpatient centers over a one-year period. Up to 30% of these antimicrobials are prescribed inappropriately, as per national guidelines. The predominant reasons include (i) failure to de-escalate to a more narrow-spectrum antimicrobial, (ii) criteria for infection, especially skin and soft tissue infections, are not met, and (iii) indications and duration for surgical prophylaxis for minor vascular-access-related procedures do not follow recommended guidelines. Vancomycin, third- or fourth-generation cephalosporins and cefazolin are the most common antimicrobials or antimicrobial classes prescribed inappropriately. Antimicrobial stewardship programs reduce both inappropriate antimicrobial exposure and associated costs. Effective strategies include (i) education, (ii) guidelines and clinical pathways, (iii) antimicrobial order forms, (iv) de-escalation therapy, and (v) prospective audit and feedback. Dialysis centers need to identify a team of individuals that will lead the antimicrobial stewardship program. Administrative and financial support for this team is essential. After implementation of the program, regular monitoring for compliance with strategies, and identifying factors that are preventing compliance are necessary. The efficacy of the program should also be evaluated at regular intervals through process and outcome measures. PMID:23600755

  13. Antimicrobial resistance of three species of Bacillus to thirty various antimicrobial agents.

    PubMed

    Moldenhauer, J E; Bass, S; Rubio, S L

    1996-01-01

    Three frequently used strains of Bacillus were tested using antimicrobial susceptibility test discs to determine their resistance to various antimicrobial drug agents. The organisms selected were B. subtilis ATCC 6633 (used for USP B and F tests), B. stearothermophilus ATCC 12980 (used as a biological indicator for steam sterilization) and B. coagulans ATCC 51232 (used as a biological indicator for steam sterilization). The results indicated that for the thirty antimicrobial drug agents tested, the only organisms which exhibited any resistance to these agents was B. subtilis, and it only showed resistance to two drugs (Aztreonam and Bacitracin). PMID:8973119

  14. Using genomics to identify novel antimicrobials.

    PubMed

    Kim, W H; Lillehoj, H S; Gay, C G

    2016-04-01

    There is a critical need in animal agriculture to develop novel antimicrobials and alternative strategies that will help to reduce the use of antibiotics and address the challenges of antimicrobial resistance. High-throughput gene expression analysis is providing new tools that are enabling the discovery of host-derived antimicrobial peptides. Examples of gene-encoded natural antibiotics that have gained attention include antimicrobial peptides such as human granulysin and its multi-species homolog, namely NK-lysin, which provide a protective response against a broad range of microbes and are a principal component of innate immunity in vertebrates. Both granulysin and NK-lysin are localised in cytolytic granules in natural killer and cytotoxic T lymphocytes. Host-derived NK-lysins that were first described in mammals are also found in avian species, and they have been shown to have antimicrobial activities that could potentially be used to control important poultry pathogens. Morphological alterations observed following chicken NK-lysin binding to Eimeria sporozoites and Escherichia coli membranes indicate damage and disruption of cell membranes, suggesting that NK-lysin kills pathogenic protozoans and bacteria by direct interaction. Genotype analysis revealed that chicken NK-lysin peptides derived from certain alleles were more effective at killing pathogens than those derived from others, which could potentially affect susceptibility to diseases. Although the host-derived antimicrobial peptides described in this paper may not, by themselves, be able to replace the antibiotics currently used in animal production, their use as specific treatments based on their known mechanisms of action is showing promising results. PMID:27217171

  15. Antimicrobials in animal agriculture: parables and policy.

    PubMed

    Scott, H M; Midgley, G; Loneragan, G H

    2015-04-01

    In addition to the scientific, economic, regulatory and other policy factors that impact on antimicrobial decision-making in different jurisdictions around the world, there exist ethical, social and cultural bases for the contemporary use of these products in animal agriculture. Thus, the use of the word 'parable' to describe the contemporary moral stories that help to guide ethical antimicrobial use practices and broader policy decisions in animal agriculture is appropriate. Several of these stories reflect difficult decisions that arise from conflicting moral imperatives (i.e. both towards animal welfare and towards human health). Understanding the factors that combine to define the past and present paradigms of antimicrobial usage is crucial to mapping a path forward. There exist barriers, as well as opportunities, for advancing scenarios for reducing antimicrobial usage under a variety of voluntary, regulatory and legal policy frameworks. Any new approaches will ideally be structured to extend the use of present-day antimicrobials into the future, to provide novel alternatives for regulating any newly introduced antimicrobial products so as to maximize their useful life span and to ensure the optimal use of these products in animal agriculture to protect not only the health of animals and the interests of animal health/agriculture stakeholders, but also the human health and the interests of the public at large. A full range of policy approaches, which span the realm from strictly enforced regulations and laws to voluntary guidelines and compliance, should be explored with respect to their risks and benefits in a variety of worldwide settings and in full consideration of a range of stakeholder values. PMID:25903491

  16. Perception, Attitude, and Knowledge Regarding Antimicrobial Resistance, Appropriate Antimicrobial Use, and Infection Control Among Future Medical Practitioners: A Multicenter Study.

    PubMed

    Chuenchom, Nuttagarn; Thamlikitkul, Visanu; Chaiwarith, Romanee; Deoisares, Rawisut; Rattanaumpawan, Pinyo

    2016-05-01

    A questionnaire-based study was conducted among final-year Thai medical students. The problem of antimicrobial resistance is well recognized, but their knowledge of antimicrobial resistance, appropriate antimicrobial use, and infection control was substantially limited. Only half of these students recognized existence of an antimicrobial stewardship program or infection control unit in their hospitals. Infect Control Hosp Epidemiol 2016;37:603-605. PMID:26809753

  17. SecA: a potential antimicrobial target.

    PubMed

    Chaudhary, Arpana S; Chen, Weixuan; Jin, Jinshan; Tai, Phang C; Wang, Binghe

    2015-01-01

    There is a consensus in the medical profession of the pressing need for novel antimicrobial agents due to issues related to drug resistance. In practice, solutions to this problem to a large degree lie with the identification of new and vital targets in bacteria and subsequently designing their inhibitors. We consider SecA a very promising antimicrobial target. In this review, we compile and analyze information available on SecA to show that inhibition of SecA has a multitude of consequences. Furthermore, we discuss issues critical to the design and evaluation of SecA inhibitors. PMID:26062397

  18. Antimicrobial Action of Compounds from Marine Seaweed.

    PubMed

    Pérez, María José; Falqué, Elena; Domínguez, Herminia

    2016-03-01

    Seaweed produces metabolites aiding in the protection against different environmental stresses. These compounds show antiviral, antiprotozoal, antifungal, and antibacterial properties. Macroalgae can be cultured in high volumes and would represent an attractive source of potential compounds useful for unconventional drugs able to control new diseases or multiresistant strains of pathogenic microorganisms. The substances isolated from green, brown and red algae showing potent antimicrobial activity belong to polysaccharides, fatty acids, phlorotannins, pigments, lectins, alkaloids, terpenoids and halogenated compounds. This review presents the major compounds found in macroalga showing antimicrobial activities and their most promising applications. PMID:27005637

  19. Strategies for targeted antimicrobial photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Verma, Sarika; Sallum, Ulysses; Zheng, Xiang; Hasan, Tayyaba

    2009-06-01

    The photophysics and mechanisms of cell killing by photodynamic therapy (PDT) have been extensively studied in recent years, and PDT has received regulatory approval for the treatment of a number of diseases worldwide. As the application of this treatment modality expands with regard to both anatomical sites and diseases, it is important to develop strategies for enhancing PDT outcomes. Our group has focused on developing targeting strategies to enhance PDT for both cancerous as well as anti-microbial applications. In this article, we will discuss photosensitizer modification and conjugation strategies for targeted antimicrobial photodynamic therapy.

  20. Antimicrobial Action of Compounds from Marine Seaweed

    PubMed Central

    Pérez, María José; Falqué, Elena; Domínguez, Herminia

    2016-01-01

    Seaweed produces metabolites aiding in the protection against different environmental stresses. These compounds show antiviral, antiprotozoal, antifungal, and antibacterial properties. Macroalgae can be cultured in high volumes and would represent an attractive source of potential compounds useful for unconventional drugs able to control new diseases or multiresistant strains of pathogenic microorganisms. The substances isolated from green, brown and red algae showing potent antimicrobial activity belong to polysaccharides, fatty acids, phlorotannins, pigments, lectins, alkaloids, terpenoids and halogenated compounds. This review presents the major compounds found in macroalga showing antimicrobial activities and their most promising applications. PMID:27005637

  1. Antimicrobial hasubanalactam alkaloid from Stephania glabra.

    PubMed

    Semwal, Deepak Kumar; Rawat, Usha

    2009-03-01

    A novel hasubanalactam alkaloid, named glabradine, has been isolated from the tubers of Stephania glabra, together with three known quaternary protoberberine alkaloids, palmatine, dehydrocorydalmine and stepharanine. The structure of glabradine was assigned as 7-O-demethyl-N,O-dimethyloxostephinine, by means of rigorous spectroscopic analysis including 2 D NMR measurements. It was evaluated for antimicrobial activity against Staphylococcus aureus, S. mutans, Microsporum gypseum, M. canis and Trichophyton rubrum and displayed potent antimicrobial activity superior to those of novobiocin and erythromycin used as positive controls. PMID:19148860

  2. SecA: a potential antimicrobial target

    PubMed Central

    Chaudhary, Arpana S; Chen, Weixuan; Jin, Jinshan; Tai, Phang C; Wang, Binghe

    2015-01-01

    There is a consensus in the medical profession of the pressing need for novel antimicrobial agents due to issues related to drug resistance. In practice, solutions to this problem to a large degree lie with the identification of new and vital targets in bacteria and subsequently designing their inhibitors. We consider SecA a very promising antimicrobial target. In this review, we compile and analyze information available on SecA to show that inhibition of SecA has a multitude of consequences. Furthermore, we discuss issues critical to the design and evaluation of SecA inhibitors. PMID:26062397

  3. Antimicrobial Stewardship for the Infection Control Practitioner.

    PubMed

    Nagel, Jerod L; Kaye, Keith S; LaPlante, Kerry L; Pogue, Jason M

    2016-09-01

    Antibiotic misuse is a serious patient safety concern and a national public health priority. Years of indiscriminant antibiotic use has promoted selection for antibiotic resistant bacteria and Clostridium difficile This crisis has led to clinicians being faced with managing untreatable infections, often in the most vulnerable patient populations. This review summarizes the goals of antimicrobial stewardship programs, the essential members needed to initiate a program, various antimicrobial stewardship strategies, the role of the infection control practitioner in stewardship, barriers to its implementation and maintenance, approaches to measure the impact of a program, and the steps needed to initiate a program. PMID:27515147

  4. Octenidine dihydrochloride: chemical characteristics and antimicrobial properties.

    PubMed

    Assadian, Ojan

    2016-03-01

    The empiric use of antibiotics is being restricted due to the spread of antimicrobial resistance. However, topical antiseptics are less likely to induce resistance, owing to their unspecific mode of action and the high concentrations in which they can be used. One such antiseptic, octenidine dihydrochloride (OCT), can be used either prophylactically or therapeutically on the skin, mucosa and wounds. Evidence to support its use comes from in-vitro, animal and clinical studies on its safety, tolerability and efficacy. This article summarises the physical, chemical and antimicrobial properties of OCT in the context of wound care. PMID:26949863

  5. Fate and transport of antimicrobials and antimicrobial resistance genes in soil and runoff following land application of swine slurry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to the use of antimicrobials in livestock production, residual antimicrobials and antimicrobial resistance genes (ARGs) could enter the environment following the land application of animal wastes and could further contaminate surface and groundwater. The objective of this study was to determine ...

  6. Molecular target of synthetic antimicrobial oligomer in bacterial membranes

    NASA Astrophysics Data System (ADS)

    Yang, Lihua; Gordon, Vernita; Som, Abhigyan; Cronan, John; Tew, Gregory; Wong, Gerard

    2008-03-01

    Antimicrobial peptides comprises a key component of innate immunity for a wide range of multicellular organisms. It has been shown that natural antimicrobial peptides and their synthetic analogs have demonstrated broad-spectrum antimicrobial activity via permeating bacterial membranes selectively. Synthetic antimicrobials with tunable structure and toxicological profiles are ideal for investigations of selectivity mechanisms. We investigate interactions and self-assembly using a prototypical family of antimicrobials based on phenylene ethynylene. Results from synchrotron small angle x-ray scattering (SAXS) results and in vitro microbicidal assays on genetically modified `knock-out' bacteria will be presented.

  7. The ins and outs of periodontal antimicrobial therapy.

    PubMed

    Jorgensen, Michael G; Slots, Jørgen

    2002-04-01

    A multifaceted antimicrobial approach is necessary for the successful management of destructive periodontal disease. Effective antimicrobial periodontal therapy aims to overwhelm periodontal pathogens with aggressive initial therapy and prevent previously suppressed pathogens from rising up anew through daily oral hygiene measures and frequent professional cleaning. Current antimicrobial periodontal therapy employs mechanical debridement performed with and without surgery, antibiotics, and antiseptics. Subgingival irrigation with povidone-iodine at the dentist's office and subgingival irrigation with dilute sodium hypochlorite for home-care constitute effective, safe, and affordable periodontal antimicrobial therapy. This article describes theoretical and practical guidelines for implementing rational and cost-effective antimicrobial principles in the management of periodontal disease. PMID:12005374

  8. Antimicrobial Polymeric Materials with Quaternary Ammonium and Phosphonium Salts

    PubMed Central

    Xue, Yan; Xiao, Huining; Zhang, Yi

    2015-01-01

    Polymeric materials containing quaternary ammonium and/or phosphonium salts have been extensively studied and applied to a variety of antimicrobial-relevant areas. With various architectures, polymeric quaternary ammonium/phosphonium salts were prepared using different approaches, exhibiting different antimicrobial activities and potential applications. This review focuses on the state of the art of antimicrobial polymers with quaternary ammonium/phosphonium salts. In particular, it discusses the structure and synthesis method, mechanisms of antimicrobial action, and the comparison of antimicrobial performance between these two kinds of polymers. PMID:25667977

  9. Antimicrobial Resistance of Faecal Escherichia coli Isolates from Pig Farms with Different Durations of In-feed Antimicrobial Use.

    PubMed

    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. Comparative evaluation of silver-containing antimicrobial dressings and drugs.

    PubMed

    Castellano, Joseph J; Shafii, Susan M; Ko, Francis; Donate, Guillermo; Wright, Terry E; Mannari, Rudolph J; Payne, Wyatt G; Smith, David J; Robson, Martin C

    2007-06-01

    Wound dressings containing silver as antimicrobial agents are available in various forms and formulations; however, little is understood concerning their comparative efficacy as antimicrobial agents. Eight commercially available silver-containing dressings, Acticoat 7, Acticoat Moisture Control, Acticoat Absorbent, Silvercel, Aquacel Ag, Contreet F, Urgotol SSD and Actisorb, were tested to determine their comparative antimicrobial effectiveness in vitro and compared against three commercially available topical antimicrobial creams, a non treatment control, and a topical silver-containing antimicrobial gel, Silvasorb. Zone of inhibition and quantitative testing was performed by standard methods using Escherichia coli, Pseudomonas aeruginosa, Streptococcus faecalis and Staphylococcus aureus. Results showed all silver dressings and topical antimicrobials displayed antimicrobial activity. Silver-containing dressings with the highest concentrations of silver exhibited the strongest bacterial inhibitive properties. Concreet F and the Acticoat dressings tended to have greater antimicrobial activity than did the others. Topical antimicrobial creams, including silver sulfadiazine, Sulfamylon and gentamicin sulfate, and the topical antimicrobial gel Silvasorb exhibited superior bacterial inhibition and bactericidal properties, essentially eliminating all bacterial growth at 24 hours. Silver-containing dressings are likely to provide a barrier to and treatment for infection; however, their bactericidal and bacteriostatic properties are inferior to commonly used topical antimicrobial agents. PMID:17651227

  11. Antimicrobial functionalized genetically engineered spider silk

    PubMed Central

    Gomes, Sílvia; Leonor, Isabel B.; Mano, João F.; Reis, Rui L.; Kaplan, David L.

    2011-01-01

    Genetically engineered fusion proteins offer potential as multifunctional biomaterials for medical use. Fusion or chimeric proteins can be formed using recombinant DNA technology by combining nucleotide sequences encoding different peptides or proteins that are otherwise not found together in nature. In the present study, three new fusion proteins were designed, cloned and expressed and assessed for function, by combining the consensus sequence of dragline spider silk with three different antimicrobial peptides. The human antimicrobial peptides human neutrophil defensin 2 (HNP-2), human neutrophil defensins 4 (HNP-4) and hepcidin were fused to spider silk through bioengineering. The spider silk domain maintained its self-assembly features, a key aspect of these new polymeric protein biomaterials, allowing the formation of β-sheets to lock in structures via physical interactions without the need for chemical cross-linking. These new functional silk proteins were assessed for antimicrobial activity against Gram - Escherichia coli and Gram + Staphylococcus aureus and microbicidal activity was demonstrated. Dynamic light scattering was used to assess protein aggregation to clarify the antimicrobial patterns observed. Attenuated-total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and circular dichroism (CD) were used to assess the secondary structure of the new recombinant proteins. In vitro cell studies with a human osteosarcoma cell line (SaOs-2) demonstrated the compatibility of these new proteins with mammalian cells. PMID:21458065

  12. Use of Biopolymers in Antimicrobial Food Packaging

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent outbreaks of foodborne illness and food recalls continue to push for innovative ways to inhibit microbial growth in foods. As an additional hurdle to food processes, antimicrobial food packaging can play an important role in reducing the risk of pathogen contamination of processed foods. In...

  13. Antimicrobial packaging for fresh-cut fruits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fresh-cut fruits are minimally processed produce which are consumed directly at their fresh stage without any further kill step. Microbiological quality and safety are major challenges to fresh-cut fruits. Antimicrobial packaging is one of the innovative food packaging systems that is able to kill o...

  14. An insect pupal cell with antimicrobial properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil-dwelling insects have developed various defense mechanisms to defend against pathogen infection. The pecan weevil, Curculio caryae, spends two to three years in the soil inside an earthen cell. We hypothesized that the cell may possess antimicrobial properties. In a laboratory study, we teste...

  15. An Alternative Antimicrobial Commercial Egg Washing Procedure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Presently, commercial eggs are washed with water containing an alkali detergent at approximately pH 11 followed by a chlorine rinse. At this pH, it is likely that there is little, if any, free chlorine in the final rinse to act as an antimicrobial against pathogens like Salmonella. Using a chlorine ...

  16. Topical antimicrobials for burn wound infections.

    PubMed

    Dai, T; Huang, Y Y; Sharma, S K; Hashmi, J T; Kurup, D B; Hamblin, M R

    2010-06-01

    Throughout most of history, serious burns occupying a large percentage of body surface area were an almost certain death sentence because of subsequent infection. A number of factors such as disruption of the skin barrier, ready availability of bacterial nutrients in the burn milieu, destruction of the vascular supply to the burned skin, and systemic disturbances lead to immunosuppression combined together to make burns particularly susceptible to infection. In the 20th century the introduction of antibiotic and antifungal drugs, the use of topical antimicrobials that could be applied to burns, and widespread adoption of early excision and grafting all helped to dramatically increase survival. However the relentless increase in microbial resistance to antibiotics and other antimicrobials has led to a renewed search for alternative approaches to prevent and combat burn infections. This review will cover patented strategies that have been issued or filed with regard to new topical agents, preparations, and methods of combating burn infections. Animal models that are used in preclinical studies are discussed. Various silver preparations (nanocrystalline and slow release) are the mainstay of many approaches but antimicrobial peptides, topical photodynamic therapy, chitosan preparations, new iodine delivery formulations, phage therapy and natural products such as honey and essential oils have all been tested. This active area of research will continue to provide new topical antimicrobials for burns that will battle against growing multidrug resistance. PMID:20429870

  17. Phytoaccumulation of antimicrobials by hydroponic Cucurbita pepo.

    PubMed

    Aryal, Niroj; Reinhold, Dawn

    2013-01-01

    Consumer use of antimicrobial-containing products continuously introduces triclocarban and triclosan into the environment. Triclocarban and triclosan adversely affect plants and animals and have the potential to affect human health. Research examined the phytoaccumulation of triclocarban and triclosan by pumpkin (Cucurbita pepo cultivar Howden) and zucchini (Cucurbita pepo cultivar Gold Rush) grown hydroponically. Pumpkin and zucchini were grown in nutrient solution spiked with 0.315 microg/mL triclocarban and 0.289 microg/mL triclosan for two months. Concentrations of triclocarban and triclosan in nutrient solutions were monitored weekly. At the end of the trial, roots and shoots were analyzed for triclocarban and triclosan. Research demonstrated that pumpkin and zucchini accumulated triclocarban and triclosan. Root accumulation factors were 1.78 and 0.64 and translocation factors were 0.001 and 0.082 for triclocarban and triclosan, respectively. The results of this experiment were compared with a previous soil column study that represented environmentally relevant exposure of antimicrobials from biosolids and had similar root mass. Plants were not as efficient in removing triclocarban and triclosan in hydroponic systems as in soil systems. Shoot concentrations of antimicrobials were the same or lower in hydroponic systems than in soil columns, indicating that hydroponic system does not overpredict the concentrations of antimicrobials. PMID:23487999

  18. NATIONAL ANTIMICROBIAL RESISTANCE MONITORING SYSTEM (NARMS)

    EPA Science Inventory

    The main activity of NARMS is to monitor antimicrobial resistance of human enteric bacteria, including Campylobacter, Salmonella, Escherichia coli O157, and Shigella. NARMS is an active surveillance system that collects every 10th non-typhi Salmonella and Shigella isolate, every ...

  19. Antimicrobial resistance of enterococci from animals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is increasing concern over antimicrobial resistance in bacteria of animal and human origin including the possibility of transfer of resistance genes between animal to human bacteria, particularly, those that may be pathogenic. The reported increases in resistance are thought to result from ant...

  20. Helical antimicrobial polypeptides with radial amphiphilicity

    PubMed Central

    Xiong, Menghua; Lee, Michelle W.; Mansbach, Rachael A.; Song, Ziyuan; Bao, Yan; Peek, Richard M.; Yao, Catherine; Chen, Lin-Feng; Ferguson, Andrew L.; Wong, Gerard C. L.; Cheng, Jianjun

    2015-01-01

    α-Helical antimicrobial peptides (AMPs) generally have facially amphiphilic structures that may lead to undesired peptide interactions with blood proteins and self-aggregation due to exposed hydrophobic surfaces. Here we report the design of a class of cationic, helical homo-polypeptide antimicrobials with a hydrophobic internal helical core and a charged exterior shell, possessing unprecedented radial amphiphilicity. The radially amphiphilic structure enables the polypeptide to bind effectively to the negatively charged bacterial surface and exhibit high antimicrobial activity against both gram-positive and gram-negative bacteria. Moreover, the shielding of the hydrophobic core by the charged exterior shell decreases nonspecific interactions with eukaryotic cells, as evidenced by low hemolytic activity, and protects the polypeptide backbone from proteolytic degradation. The radially amphiphilic polypeptides can also be used as effective adjuvants, allowing improved permeation of commercial antibiotics in bacteria and enhanced antimicrobial activity by one to two orders of magnitude. Designing AMPs bearing this unprecedented, unique radially amphiphilic structure represents an alternative direction of AMP development; radially amphiphilic polypeptides may become a general platform for developing AMPs to treat drug-resistant bacteria. PMID:26460016

  1. Antimicrobial Packaging using PLA-pectin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A pectin and poly(lactic acid) (PLA) composite was compounded by extrusion. A model antimicrobial polypeptide, nisin, was loaded into the composite by diffusion. The incorporation of pectin into PLA resulted in a heterogeneous biphasic structure, as revealed by scanning electronic microscopy, conf...

  2. ANTIMICROBIAL EFFICACY TESTING (IN-HOUSE)

    EPA Science Inventory

    This project initiates the in-house study of antimicrobial efficacy, growth parameters, and transport characteristics of biological contaminants. Viable and non-viable microbial analysis will be performed by growth culture and molecular biology techniques.

    Experiments w...

  3. Antimicrobial peptides in echinoderm host defense.

    PubMed

    Li, Chun; Blencke, Hans-Matti; Haug, Tor; Stensvåg, Klara

    2015-03-01

    Antimicrobial peptides (AMPs) are important effector molecules in innate immunity. Here we briefly summarize characteristic traits of AMPs and their mechanisms of antimicrobial activity. Echinoderms live in a microbe-rich marine environment and are known to express a wide range of AMPs. We address two novel AMP families from coelomocytes of sea urchins: cysteine-rich AMPs (strongylocins) and heterodimeric AMPs (centrocins). These peptide families have conserved preprosequences, are present in both adults and pluteus stage larvae, have potent antimicrobial properties, and therefore appear to be important innate immune effectors. Strongylocins have a unique cysteine pattern compared to other cysteine-rich peptides, which suggests a novel AMP folding pattern. Centrocins and SdStrongylocin 2 contain brominated tryptophan residues in their native form. This review also includes AMPs isolated from other echinoderms, such as holothuroidins, fragments of beta-thymosin, and fragments of lectin (CEL-III). Echinoderm AMPs are crucial molecules for the understanding of echinoderm immunity, and their potent antimicrobial activity makes them potential precursors of novel drug leads. PMID:25445901

  4. Topical Antimicrobials for Burn Wound Infections

    PubMed Central

    Dai, Tianhong; Huang, Ying-Ying; Sharma, Sulbha K.; Hashmi, Javad T.; Kurup, Divya B.; Hamblin, Michael R.

    2010-01-01

    Throughout most of history, serious burns occupying a large percentage of body surface area were an almost certain death sentence because of subsequent infection. A number of factors such as disruption of the skin barrier, ready availability of bacterial nutrients in the burn milieu, destruction of the vascular supply to the burned skin, and systemic disturbances lead to immunosuppression combined together to make burns particularly susceptible to infection. In the 20th century the introduction of antibiotic and antifungal drugs, the use of topical antimicrobials that could be applied to burns, and widespread adoption of early excision and grafting all helped to dramatically increase survival. However the relentless increase in microbial resistance to antibiotics and other antimicrobials has led to a renewed search for alternative approaches to prevent and combat burn infections. This review will cover patented strategies that have been issued or filed with regard to new topical agents, preparations, and methods of combating burn infections. Animal models that are used in preclinical studies are discussed. Various silver preparations (nanocrystalline and slow release) are the mainstay of many approaches but antimicrobial peptides, topical photodynamic therapy, chitosan preparations, new iodine delivery formulations, phage therapy and natural products such as honey and essential oils have all been tested. This active area of research will continue to provide new topical antimicrobials for burns that will battle against growing multi-drug resistance. PMID:20429870

  5. Swellability of Silver (I) Antimicrobial Wound Dressings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An important characteristic of moist wound dressings is their ability to swell and absorb exudates from the wound, while maintaining a moist atmosphere at the wound site. At the Southern Regional Research Center, we have developed antimicrobial silver- CM-cotton print cloth from CM-Printcloth with l...

  6. The Antimicrobial Index: a comprehensive literature-based antimicrobial database and reference work

    PubMed Central

    Amirkia, Vafa David; Qiubao, Pan

    2011-01-01

    Although the ever-growing usage of antimicrobials in the fields of medicine, pharmacology, and microbiology have undoubtedly allowed for unprecedented advances in the scientific world, these advances are nevertheless accompanied by unprecedented challenges. Sharp increases in antibiotic usages have led to inefficient and wasteful usage practices. Bacterial resistances have dramatically increased and therefore hindered the effectiveness of traditional antibiotics, thus forcing many life-science professionals to turn to plant extracts and synthetic chemicals [1]. The Antimicrobial Index (TAMI) seeks to alleviate some of these mounting difficulties through the collection and centralization of relevant antimicrobial susceptibility data from journals. Data compiled for antimicrobials include: method of action, physical properties, resistance genes, side effects, and minimal inhibitory concentrations (MIC50, MIC90 and/or ranges). TAMI currently contains data on 960 antimicrobials and over 24,000 microorganisms (3,500 unique strains) which were collected from over 400 pieces of published literature. Volume and scope of the index have been and will continue to increase and it is hoped that such an index will further foster international cooperation and communication of antimicrobial-related knowledge. TAMI can be accessed at: http://antibiotics.toku-e.com/. PMID:21383924

  7. Late Holocene Paleo-Uplift Events at the Tapion Restraining Bend in Haiti: Implications for Earthquake Recurrence in the Vicinity of the 2010 Rupture Zone

    NASA Astrophysics Data System (ADS)

    Taylor, F. W.; Mann, P.; Briggs, R. W.; Prentice, C. S.; Jean, P.; Shen, C.; Chiang, H.; Jiang, X.

    2011-12-01

    The January 12, 2010, Mw 7.0 earthquake in Haiti was caused by slip on one or more blind thrust faults north of the plate-bounding, left-lateral, strike-slip Enriquillo-Plaintain Garden fault zone (EPGFZ). Thrusting lifted ~50 km of coastline with maximum coastal uplift of 0.64 m. Prior to the 2010 event, the EPGFZ likely ruptured during the 1751 or 1770 earthquakes with left-lateral surface offsets on the main trace of the fault that range from 1.3 to 3.3 m. We mapped and dated evidence of paleo-uplifts near the topographically prominent Tapion restraining bend, an apparent right-step along the main trace of the EPGFZ. We found fossil corals that provide evidence of uplift prior to 2010 at two sites located 6.4 km apart along the steep seaward side of Tapion Ridge, but no other evidence of paleo-uplift anywhere in the 2010 uplift zone. Near the east end of Tapion, growth-position coral at ~ 1m ALC (above living coral post-2010 uplift) gave a 230Th/234U age of 2138 ± 11 yr. 2010 uplift here was ~0.37 m, so that the net uplift from 2138 ± 11 yr until the 2010 earthquake was ~0.63 m. Near the western end of Tapion, emerged in situ coral heads giving ages of 4241 ± 13 and 4346 ± 14 yr are planed off at ~0.5 m ALC and capped by a pebble conglomerate, but we estimate that these corals had extended to ~1 m ALC prior to erosion. An emerged bioerosion notch centered at 0.46 m ALC and the planed tops of the coral heads at ~0.5 m correspond well to the 0.44 m ALC of coral that lived prior to the 2010 uplift at this site. A higher emerged bioerosion notch centered at ~0.93 m ALC corresponds well to the elevation of the nearby 4241 ± 13 and 4346 ± 14 yr corals at ~1.0 m ALC prior to being planed off to ~0.5 m. The dated corals and 0.93 m ALC notch indicate ~0.5 m net uplift from ~4241 ± 13 until the 2010 earthquake. Thus, fossil corals at two sites near Tapion are now at similar elevations, but their ages are significantly different and indicate two distinct uplift ages

  8. Magnesium Based Materials and their Antimicrobial Activity

    NASA Astrophysics Data System (ADS)

    Robinson, Duane Allan

    The overall goals of this body of work were to characterize the antimicrobial properties of magnesium (Mg) metal and nano-magnesium oxide (nMgO) in vitro, to evaluate the in vitro cytotoxicity of Mg metal, and to incorporate MgO nanoparticles into a polymeric implant coating and evaluate its in vitro antimicrobial properties. In the course of this work it was found that Mg metal, Mg-mesh, and nMgO have in vitro antimicrobial properties that are similar to a bactericidal antibiotic. For Mg metal, the mechanism of this activity appears to be related to an increase in pH (i.e. a more alkaline environment) and not an increase in Mg2+. Given that Mg-mesh is a Mg metal powder, the assumption is that it has the same mechanism of activity as Mg metal. The mechanism of activity for nMgO remains to be elucidated and may be related to a combination of interaction of the nanoparticles with the bacteria and the alkaline pH. It was further demonstrated that supernatants from suspensions of Mg-mesh and nMgO had the same antimicrobial effect as was noted when the particles were used. The supernatant from Mg-mesh and nMgO was also noted to prevent biofilm formation for two Staphylococcus strains. Finally, poly-epsilon-caprolactone (PCL) composites of Mg-mesh (PCL+Mg-mesh) and nMgO (PCL+nMgO) were produced. Coatings applied to screws inhibited growth of Escherichia coli and Pseudomonas aeruginosa and in thin disc format inhibited the growth of Staphylococcus aureus in addition to the E. coli and P. aeruginosa. Pure Mg metal was noted to have some cytotoxic effect on murine fibroblast and osteoblast cell lines, although this effect needs to be characterized further. To address the need for an in vivo model for evaluating implant associated infections, a new closed fracture osteomyelitis model in the femur of the rat was developed. Magnesium, a readily available and inexpensive metal was shown to have antimicrobial properties that appear to be related to its corrosion products and

  9. CHK2–BRCA1 tumor-suppressor axis restrains oncogenic Aurora-A kinase to ensure proper mitotic microtubule assembly

    PubMed Central

    Ertych, Norman; Stolz, Ailine; Valerius, Oliver; Braus, Gerhard H.; Bastians, Holger

    2016-01-01

    BRCA1 (breast cancer type 1 susceptibility protein) is a multifunctional tumor suppressor involved in DNA damage response, DNA repair, chromatin regulation, and mitotic chromosome segregation. Although the nuclear functions of BRCA1 have been investigated in detail, its role during mitosis is little understood. It is clear, however, that loss of BRCA1 in human cancer cells leads to chromosomal instability (CIN), which is defined as a perpetual gain or loss of whole chromosomes during mitosis. Moreover, our recent work has revealed that the mitotic function of BRCA1 depends on its phosphorylation by the tumor-suppressor kinase Chk2 (checkpoint kinase 2) and that this regulation is required to ensure normal microtubule plus end assembly rates within mitotic spindles. Intriguingly, loss of the positive regulation of BRCA1 leads to increased oncogenic Aurora-A activity, which acts as a mediator for abnormal mitotic microtubule assembly resulting in chromosome missegregation and CIN. However, how the CHK2–BRCA1 tumor suppressor axis restrains oncogenic Aurora-A during mitosis to ensure karyotype stability remained an open question. Here we uncover a dual molecular mechanism by which the CHK2–BRCA1 axis restrains oncogenic Aurora-A activity during mitosis and identify BRCA1 itself as a target for Aurora-A relevant for CIN. In fact, Chk2-mediated phosphorylation of BRCA1 is required to recruit the PP6C–SAPS3 phosphatase, which acts as a T-loop phosphatase inhibiting Aurora-A bound to BRCA1. Consequently, loss of CHK2 or PP6C-SAPS3 promotes Aurora-A activity associated with BRCA1 in mitosis. Aurora-A, in turn, then phosphorylates BRCA1 itself, thereby inhibiting the mitotic function of BRCA1 and promoting mitotic microtubule assembly, chromosome missegregation, and CIN. PMID:26831064

  10. Three-dimensional structure of potato carboxypeptidase inhibitor in solution. A study using nuclear magnetic resonance, distance geometry, and restrained molecular dynamics

    SciTech Connect

    Clore, G.M.; Gronenborn, A.M.; Nilges, M.; Ryan, C.A.

    1987-12-01

    The solution conformation of potato carboxypeptidase inhibitor (CPI) has been investigated by /sup 1/H NMR spectroscopy. The spectrum is assigned in a sequential manner by using two-dimensional NMR techniques to identify through-bond and through-space (<5 A) connectivities. A set of 309 approximate interproton distance restraints is derived from the two-dimensional nuclear Overhauser enhancement spectra and used as the basis of a three-dimensional structure determination by a combination of metric matrix distance geometry and restrained molecular dynamics calculations. A total of 11 converged distance geometry structures were computed and refined by using restrained molecular dynamics. The average atomic root mean square (rms) difference between the final 11 structures and the mean structure obtained by averaging their coordinates is 1.4 +/- 0.3 A for residues 2-39 and 0.9 +/- 0.2 A for residues 5-37. The corresponding values for all atoms are 1.9 +/- 0.3 and 1.4 +/- 0.2 A, respectively. The computed structures are very close to the X-ray structure of CPI in its complex with carboxypeptidase, and the backbone atomic rms difference between the mean of the computed structures and the X-ray structure is only 1.2 A. Nevertheless, there are some real differences present which are evidenced by significant deviations between the experimental upper interproton distance limits and the corresponding interproton distances derived from the X-ray structure. These principally occur in two regions, residues 18-20 and residues 28-30, the latter comprising part of the region of secondary contact between CPI and carboxypeptidase in the X-ray structure.

  11. Quantum dots (QDs) restrain human cervical carcinoma HeLa cell proliferation through inhibition of the ROCK-c-Myc signaling.

    PubMed

    Chen, Liqun; Qu, Guangbo; Zhang, Changwen; Zhang, Shuping; He, Jiuyang; Sang, Nan; Liu, Sijin

    2013-03-01

    Cancers often cause significant morbidity and even death to patients. To date, conventional therapies, such as chemotherapy, radiation and surgery, are often limited; meanwhile, novel anticancer therapeutics are urgently needed to improve clinical treatments. Rapid application of nanotechnology and nanomaterials represents a promising vista for the development of anti-cancer therapeutics. However, how to integrate the novel properties of nanotechnology and nanomaterials into cancer treatment warrants close investigation. In the current study, we report a novel finding about the inhibitory effect of CdSe quantum dots (QDs) on Rho-associated kinase (ROCK) activity in cervical carcinoma HeLa cells associated with the attenuation of the ROCK-c-Myc signaling. We mechanistically demonstrated that QD-conducted ROCK inhibition greatly diminished c-Myc protein stability due to reduced phosphorylation, and also suppressed its activity in transcribing target genes (e.g. HSPC111). Thus, the treatment of QDs greatly restrained HeLa cell growth by inducing cell cycle arrest at G1 phase due to the reduced ability of c-Myc in driving cell proliferation. Additionally, since HSPC111, one of the c-Myc targets, is involved in regulating cell growth through ribosomal biogenesis and assembly, the downregulation of HSPC111 could also contribute to diminished proliferation in HeLa cells upon QD treatment. These results together suggested that inhibition of ROCK activity or ROCK-mediated c-Myc signaling in tumor cells upon QD treatment might represent a promising strategy to restrain tumor progression for human cervical carcinoma. PMID:23370637

  12. Antimicrobial biocompatible bioscaffolds for orthopaedic implants.

    PubMed

    Qureshi, Ammar T; Terrell, Lekeith; Monroe, W Todd; Dasa, Vinod; Janes, Marlene E; Gimble, Jeffrey M; Hayes, Daniel J

    2014-05-01

    Nationally, nearly 1.5 million patients in the USA suffer from ailments requiring bone grafts and hip and other joint replacements. Infections following internal fixation in orthopaedic trauma can cause osteomyelitis in 22-66% of cases and, if uncontrolled, the mortality rate can be as high as 2%. We characterize a procedure for the synthesis of antimicrobial and biocompatible poly-l-lactic acid (PLLA) and poly-ethyleneglycol (PEG) bioscaffolds designed to degrade and absorb at a controlled rate. The bioscaffold architecture aims to provide a suitable substrate for the controlled release of silver nanoparticles (SNPs) to reduce bacterial growth and to aid the proliferation of human adipose-derived stem cells (hASCs) for tissue-engineering applications. The fabricated bioscaffolds were characterized by scanning transmission microscope (SEM) and it showed that the addition of tncreasing concentrations of SNPs results in the formation of dendritic porous channels perpendicular to the axis of precipitation. The antimicrobial properties of these porous bioscaffolds were tested according to a modified ISO 22196 standard across varying concentrations of biomass-mediated SNPs to determine an efficacious antimicrobial concentration. The bioscaffolds reduced the Staphylococcus aureus and Escherichia coli viable colony-forming units by 98.85% and 99.9%, respectively, at an antimicrobial SNPs concentration of 2000 ppm. Human ASCs were seeded on bioscaffolds and cultured in vitro for 20 days to study the effect of SNPs concentration on the viability of cells. SEM analysis and the metabolic activity-based fluorescent dye, AlamarBlue®, demonstrated the growth of cells on the efficacious antimicrobial bioscaffolds. The biocompatibility of in vitro leached silver, quantified by inductively coupled plasma optical emission spectroscopy (ICP-OES), proved non-cytotoxic when tested against hASCs, as evaluated by MTT assay. PMID:22700366

  13. Identification of acquired antimicrobial resistance genes

    PubMed Central

    Zankari, Ea; Hasman, Henrik; Cosentino, Salvatore; Vestergaard, Martin; Rasmussen, Simon; Lund, Ole; Aarestrup, Frank M.; Larsen, Mette Voldby

    2012-01-01

    Objectives Identification of antimicrobial resistance genes is important for understanding the underlying mechanisms and the epidemiology of antimicrobial resistance. As the costs of whole-genome sequencing (WGS) continue to decline, it becomes increasingly available in routine diagnostic laboratories and is anticipated to substitute traditional methods for resistance gene identification. Thus, the current challenge is to extract the relevant information from the large amount of generated data. Methods We developed a web-based method, ResFinder that uses BLAST for identification of acquired antimicrobial resistance genes in whole-genome data. As input, the method can use both pre-assembled, complete or partial genomes, and short sequence reads from four different sequencing platforms. The method was evaluated on 1862 GenBank files containing 1411 different resistance genes, as well as on 23 de-novo-sequenced isolates. Results When testing the 1862 GenBank files, the method identified the resistance genes with an ID = 100% (100% identity) to the genes in ResFinder. Agreement between in silico predictions and phenotypic testing was found when the method was further tested on 23 isolates of five different bacterial species, with available phenotypes. Furthermore, ResFinder was evaluated on WGS chromosomes and plasmids of 30 isolates. Seven of these isolates were annotated to have antimicrobial resistance, and in all cases, annotations were compatible with the ResFinder results. Conclusions A web server providing a convenient way of identifying acquired antimicrobial resistance genes in completely sequenced isolates was created. ResFinder can be accessed at www.genomicepidemiology.org. ResFinder will continuously be updated as new resistance genes are identified. PMID:22782487

  14. Repurposing celecoxib as a topical antimicrobial agent

    PubMed Central

    Thangamani, Shankar; Younis, Waleed; Seleem, Mohamed N.

    2015-01-01

    There is an urgent need for new antibiotics and alternative strategies to combat multidrug-resistant bacterial pathogens, which are a growing clinical issue. Repurposing existing approved drugs with known pharmacology and toxicology is an alternative strategy to accelerate antimicrobial research and development. In this study, we show that celecoxib, a marketed inhibitor of cyclooxygenase-2, exhibits broad-spectrum antimicrobial activity against Gram-positive pathogens from a variety of genera, including Staphylococcus, Streptococcus, Listeria, Bacillus, and Mycobacterium, but not against Gram-negative pathogens. However, celecoxib is active against all of the Gram-negative bacteria tested, including strains of, Acinetobacter, and Pseudomonas, when their intrinsic resistance is artificially compromised by outer membrane permeabilizing agents such as colistin. The effect of celecoxib on incorporation of radioactive precursors into macromolecules in Staphylococcus aureus was examined. The primary antimicrobial mechanism of action of celecoxib was the dose-dependent inhibition of RNA, DNA, and protein synthesis. Further, we demonstrate the in vivo efficacy of celecoxib in a methicillin-resistant S. aureus (MRSA) infected Caenorhabditis elegans whole animal model. Topical application of celecoxib (1 and 2%) significantly reduced the mean bacterial count in a mouse model of MRSA skin infection. Further, celecoxib decreased the levels of all inflammatory cytokines tested, including tumor necrosis factor-α, interleukin-6, interleukin-1 beta, and monocyte chemo attractant protein-1 in wounds caused by MRSA infection. Celecoxib also exhibited synergy with many conventional antimicrobials when tested against four clinical isolates of S. aureus. Collectively, these results demonstrate that celecoxib alone, or in combination with traditional antimicrobials, has a potential to use as a topical drug for the treatment of bacterial skin infections. PMID:26284040

  15. Topical antimicrobials for burn infections - an update.

    PubMed

    Sevgi, Mert; Toklu, Ani; Vecchio, Daniela; Hamblin, Michael R

    2013-12-01

    The relentless rise in antibiotic resistance among pathogenic bacteria and fungi, coupled with the high susceptibility of burn wounds to infection, and the difficulty of systemically administered antibiotics to reach damaged tissue, taken together have made the development of novel topical antimicrobials for burn infections a fertile area of innovation for researchers and companies. We previously covered the existing patent literature in this area in 2010, but the notable progress made since then, has highlighted the need for an update to bring the reader up to date on recent developments. New patents in the areas of topically applied antibiotics and agents that can potentiate the action of existing antibiotics may extend their useful lifetime. Developments have also been made in biofilm-disrupting agents. Antimicrobial peptides are nature's way for many life forms to defend themselves against attack by pathogens. Silver has long been known to be a highly active antimicrobial but new inorganic metal derivatives based on bismuth, copper and gallium have emerged. Halogens such as chlorine and iodine can be delivered by novel technologies. A variety of topically applied antimicrobials include chitosan preparations, usnic acid, ceragenins and XF porphyrins. Natural product derived antimicrobials such as tannins and essential oils have also been studied. Novel techniques to deliver reactive oxygen species and nitric oxide in situ have been developed. Light-mediated techniques include photodynamic therapy, ultraviolet irradiation, blue light, low-level laser therapy and titania photocatalysis. Passive immunotherapy employs antibodies against pathogens and their virulence factors. Finally an interesting new area uses therapeutic microorganisms such as phages, probiotic bacteria and protozoa to combat infections. PMID:24215506

  16. Oral antimicrobials increase antimicrobial resistance in porcine E. coli--a systematic review.

    PubMed

    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 <1.0, respectively. Eleven studies, describing 36 different trials, fulfilled the eligibility criteria and were finally assessed. An increase of AMR in E. coli was found in 10 out of 11 trials comparing AMR after with AMR prior to oral treatment and in 22 of the 25 trials comparing orally treated with untreated groups. Effects expressed as odds or prevalence ratios were highest for the use of aminoglycosides, quinolones and tetracycline. There was no clear association between the reported dosage and AMR towards tetracycline. Information on 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

  17. Understanding antimicrobial stewardship: Disease severity treatment thresholds and antimicrobial alternatives among organic and conventional calf producers.

    PubMed

    Habing, Greg; Djordjevic, Catherine; Schuenemann, Gustavo M; Lakritz, Jeff

    2016-08-01

    Reductions in livestock antimicrobial use (AMU) can be achieved through identification of effective antimicrobial alternatives as well as accurate and stringent identification of cases requiring antimicrobial therapy. Objective measurements of selectivity that incorporate appropriate case definitions are necessary to understand the need and potential for reductions in AMU through judicious use. The objective of this study was to measure selectivity using a novel disease severity treatment threshold for calf diarrhea, and identify predictors of more selective application of antimicrobials among conventional dairy producers. A second objective of this study was to describe the usage frequency and perceptions of efficacy of common antimicrobial alternatives among conventional and organic producers. The cross-sectional survey was mailed to Michigan and Ohio, USA dairy producers and contained questions on AMU attitudes, AMU practices, veterinary-written protocols, and antimicrobial alternatives. The treatment threshold, defined based on the case severity where the producer would normally apply antimicrobials, was identified with a series of descriptions with increasing severity, and ordinal multivariable logistic regression was used to determine the association between the treatment threshold and individual or herd characteristics. The response rate was 49% (727/1488). Overall, 42% of conventional producers reported any veterinary-written treatment protocol, and 27% (113/412) of conventional producers had a veterinary-written protocol for the treatment of diarrhea that included a case identification. The majority (58%, 253/437) of conventional producers, but a minority (7%) of organic producers disagreed that antibiotic use in agriculture led to resistant bacterial infections in people. Among conventional producers, the proportion of producers applying antimicrobials for therapy increased from 13% to 67% with increasing case severity. The treatment threshold was low

  18. A Shrimp C-type Lectin Inhibits Proliferation of the Hemolymph Microbiota by Maintaining the Expression of Antimicrobial Peptides*

    PubMed Central

    Wang, Xian-Wei; Xu, Ji-Dong; Zhao, Xiao-Fan; Vasta, Gerardo Raul; Wang, Jin-Xing

    2014-01-01

    Some aquatic invertebrates such as shrimp contain low albeit stable numbers of bacteria in the circulating hemolymph. The proliferation of this hemolymph microbiota in such a nutrient-rich environment is tightly controlled in healthy animals, but the mechanisms responsible had remained elusive. In the present study, we report a C-type lectin (MjHeCL) from the kuruma shrimp (Marsupenaeus japonicus) that participates in restraining the hemolymph microbiota. Although the expression of MjHeCL did not seem to be modulated by bacterial challenge, the down-regulation of its expression by RNA interference led to proliferation of the hemolymph microbiota, ultimately resulting in shrimp death. This phenotype was rescued by the injection of recombinant MjHeCL, which restored the healthy status of the knockdown shrimp. A mechanistic analysis revealed that MjHeCL inhibited bacterial proliferation by modulating the expression of antimicrobial peptides. The key function of MjHeCL in the shrimp immune homeostasis might be related to its broader recognition spectrum of the hemolymph microbiota components than other lectins. Our study demonstrates the role of MjHeCL in maintaining the healthy status of shrimp and provides new insight into the biological significance of C-type lectins, a diversified and abundant lectin family in invertebrate species. PMID:24619414

  19. Engaging hospitalists in antimicrobial stewardship: Lessons from a multihospital collaborative.

    PubMed

    Mack, Megan R; Rohde, Jeffrey M; Jacobsen, Diane; Barron, James R; Ko, Christin; Goonewardene, Michael; Rosenberg, David J; Srinivasan, Arjun; Flanders, Scott A

    2016-08-01

    Inappropriate antimicrobial use in hospitalized patients contributes to antimicrobial-resistant infections and complications. We sought to evaluate the impact, barriers, and facilitators of antimicrobial stewardship best practices in a diverse group of hospital medicine programs. This multihospital initiative included 1 community nonteaching hospital, 2 community teaching hospitals, and 2 academic medical centers participating in a collaborative with the Centers for Disease Control and Prevention and the Institute for Healthcare Improvement. We conducted multimodal physician education on best practices for antimicrobial use including: (1) enhanced antimicrobial documentation, (2) improved quality and accessibility of local clinical guidelines, and (3) a 72-hour antimicrobial "timeout." Implementation barriers included variability in physician practice styles, lack of awareness of stewardship importance, and overly broad interventions. Facilitators included engaging hospitalists, collecting real time data and providing performance feedback, and appropriately limiting the scope of interventions. In 2 hospitals, complete antimicrobial documentation in sampled medical records improved significantly (4% to 51% and 8% to 65%, P < 0.001 for each comparison). A total of 726 antimicrobial timeouts occurred at 4 hospitals, and 30% resulted in optimization or discontinuation of antimicrobials. With careful attention to key barriers and facilitators, hospitalists can successfully implement effective antimicrobial stewardship practices. Journal of Hospital Medicine 2016;11:576-580. © 2016 Society of Hospital Medicine. PMID:27130473

  20. Antimicrobial use on 24 beef farms in Ontario.

    PubMed

    Carson, Carolee A; Reid-Smith, Richard; Irwin, Rebecca J; Martin, Wayne S; McEwen, Scott A

    2008-01-01

    Understanding risk factors for antimicrobial resistance requires knowledge of antimicrobial selection pressure. The objectives of this research were to develop methodology for collecting quantitative antimicrobial use information from beef producers in Ontario, to document the types and quantities of antimicrobials reported (for a minimum of 12 mo), and to compare 2 metrics for injectable use reporting. Twenty-four volunteer beef producers were asked to complete a questionnaire, document drug use in a treatment diary, and retain empty medication containers. For injectable antimicrobials, producers recorded approximately 60% of the total use in the treatment diaries; oxytetracycline, penicillin, macrolides, florfenicol, and spectinomycin were used in the greatest quantities. Based on estimated weights of active ingredients (calculated according to number of animals exposed, duration, and average dose per day) the antimicrobials most commonly used in feed were monensin, tylosin, lasalocid, and tetracyclines. The antimicrobials most commonly used in water were lincomycin-spectinomycin, chlortetracycline, and oxytetracycline. Based on estimated weights and measured quantities, < 1% of antimicrobials used were in the Canadian category of highest importance to human medicine. A comparison of animal daily dosages to kilograms of active ingredient demonstrated that the relative ranking of use of antimicrobials varied with the chosen metric, and that further investigation into the best measure in relation to antimicrobial resistance is warranted. PMID:18505199

  1. Antimicrobial resistance in bacteria from Swiss veal calves at slaughter.

    PubMed

    Di Labio, E; Regula, G; Steiner, A; Miserez, R; Thomann, A; Ledergerber, U

    2007-01-01

    Bacteria with antimicrobial resistance can be transferred from animals to humans and may compromise antimicrobial treatment in case of infection. To determine the antimicrobial resistance situation in bacteria from Swiss veal calves, faecal samples from 500 randomly selected calves originating from 129 farms were collected at four big slaughterhouses. Samples were cultured for Escherichia coli, Enterococcus sp. and Campylobacter sp. and isolated strains were tested for antimicrobial susceptibility to selected antimicrobial agents by the minimal inhibitory concentration technique using the broth microdilution method. From 100 farms, data on farm management, animal husbandry and antimicrobial treatments of the calves were collected by questionnaire. Risk factors associated with antimicrobial resistance were identified by logistic regression. In total, 467 E. coli, 413 Enterococcus sp. and 202 Campylobacter sp. were isolated. Of those, 68.7%, 98.7% and 67.8%, respectively, were resistant to at least one of the tested antimicrobial agents. Resistance was mainly observed to antimicrobials frequently used in farm animals. Prevalence of resistance to antimicrobials important for human treatment was generally low. However, a rather high number of quinupristin/dalfopristin-resistant Enterococcus faecium and ciprofloxacin-resistant Campylobacter sp. were detected. External calf purchase, large finishing groups, feeding of milk by-products and administration of antimicrobials through feed upon arrival of the animals on the farm significantly increased the risk of antimicrobial resistance at farm level. Participation in a quality assurance programme and injection of a macrolide upon arrival of the animals on the farm had a protective effect. The present study showed that veal calves may serve as a reservoir for resistant bacteria. To ensure food safety, veal calves should be included in the national monitoring programme for antimicrobial resistance in farm animals. By

  2. Antimicrobial resistance in Libya: 1970–2011

    PubMed Central

    Ghenghesh, Khalifa Sifaw; Rahouma, Amal; Tawil, Khaled; Zorgani, Abdulaziz; Franka, Ezzedin

    2013-01-01

    Resistance to antimicrobial agents is a major health problem that affects the whole world. Providing information on the past state of antimicrobial resistance in Libya may assist the health authorities in addressing the problem more effectively in the future. Information was obtained mainly from Highwire Press (including PubMed) search for the period 1970–2011 using the terms ‘antibiotic resistance in Libya’, ‘antimicrobial resistance in Libya’, ‘tuberculosis in Libya’, and ‘primary and acquired resistance in Libya’ in title and abstract. From 1970 to 2011 little data was available on antimicrobial resistance in Libya due to lack of surveillance and few published studies. Available data shows high resistance rates for Salmonella species in the late 1970s and has remained high to the present day. High prevalence rates (54–68%) of methicillin-resistant Staphylococcus aureus (MRSA) were reported in the last decade among S. aureus from patients with burns and surgical wound infections. No reports were found of vancomycin-resistant S. aureus (VRSA) or vancomycin-intermediate-resistant S. aureus (VISA) using standard methods from Libya up to the end of 2011. Reported rates of primary (i.e. new cases) and acquired (i.e. retreatment cases) multidrug-resistant tuberculosis (MDR-TB) from the eastern region of Libya in 1971 were 16.6 and 33.3% and in 1976 were 8.6 and 14.7%, in western regions in 1984–1986 were 11 and 21.5% and in the whole country in 2011 were estimated at 3.4 and 29%, respectively. The problem of antibiotic resistance is very serious in Libya. The health authorities in particular and society in general should address this problem urgently. Establishing monitoring systems based on the routine testing of antimicrobial sensitivity and education of healthcare workers, pharmacists, and the community on the health risks associated with the problem and benefits of prudent use of antimicrobials are some steps that can be taken to tackle the

  3. [Antimicrobial activity exerted by sodium dichloroisocyanurate].

    PubMed

    D'Auria, F D; Simonetti, G; Strippoli, V

    1989-01-01

    Sodium dichloroisocyanurate is a chlorinated cleaner. It was used for swimming pool sanitation and for the sterilisation of linen. Not recently ago sodium dichloroisocyanurate has substituted hypochlorite for the sterilisation of infant feeding bottles and teats. Sodium dichloroisocyanurate is soluble in water; this condition causes the hydrolysis of sodium dichloroisocyanurate in hypochlorous acid, that is the active agent, isocyanurate and isocyanurate chlorine. These compounds form a chlorine protein that carry out microbicidal activity. In a toxicology study has been shown that no severe changes in the normal metabolic function occurred, furthermore sodium dichloroisocyanurate has not shown teratogenic effects at the concentration of 200 mg/kg. The antimicrobial activity of sodium dichloroisocyanurate was evaluated against Gram negative bacteria such as E. coli or Salmonella typhimurium and against some fungi. This study illustrates a rapid antimicrobial activity using concentrations. Our study concentrated on the antimicrobial activity of sodium dichloroisocyanurate in some experimental conditions. We tested 66 strains of fungi, 28 Gram positive bacteria and 29 Gram negative bacteria. We also evaluated the antimicrobial activity of sodium dichloroisocyanurate against protozoa such as Trichomonas vaginalis. The antimicrobial activity was evaluated in cultural conditions and non cultural conditions; in these experiments we observed similar action in both the commercial product and pure substance. In cultural conditions sodium dichloroisocyanurate shows a good activity against fungi and bacteria, moreover it can be observed that the serum didn't interfere with its activity. In a non cultural condition the Candida was killed rapidly by the sodium dichloroisocyanurate but this activity is influenced by the growth phase of the yeast. Against mycelial form such as Penicillium and Aspergillus the sodium dichloroisocyanurate needs a longer contact time than yeast form

  4. Controversies in Antimicrobial Stewardship: Focus on New Rapid Diagnostic Technologies and Antimicrobials

    PubMed Central

    Wenzler, Eric; Wong, Jordan R.; Goff, Debra A.; Jankowski, Christopher A.; Bauer, Karri A.

    2016-01-01

    Antimicrobial stewardship programs (ASPs) are challenged with ensuring appropriate antimicrobial use while minimizing expenditures. ASPs have consistently demonstrated improved patient outcomes and significant cost reductions but are continually required to justify the costs of their existence and interventions due to the silo mentality often adopted by hospital administrators. As new technologies and antimicrobials emerge, ASPs are in a constant tug-of-war between providing optimal clinical outcomes and ensuring cost containment. Additionally, robust data on cost-effectiveness of new rapid diagnostic technologies and antimicrobials with subsequent ASP interventions to provide justification are lacking. As the implementation of an ASP will soon be mandatory for acute care hospitals in the United States, ASPs must find ways to justify novel interventions to align themselves with healthcare administrators. This review provides a framework for the justification of implementing a rapid diagnostic test or adding a new antimicrobial to formulary with ASP intervention, reviews approaches to demonstrating cost-effectiveness, and proposes methods for which ASPs may reduce healthcare expenditures via alternative tactics. PMID:27025521

  5. Rational design of tryptophan-rich antimicrobial peptides with enhanced antimicrobial activities and specificities.

    PubMed

    Yu, Hui-Yuan; Huang, Kuo-Chun; Yip, Bak-Sau; Tu, Chih-Hsiang; Chen, Heng-Li; Cheng, Hsi-Tsung; Cheng, Jya-Wei

    2010-11-01

    Trp-rich antimicrobial peptides play important roles in the host innate defense mechanism of many plants and animals. A series of short Trp-rich peptides derived from the C-terminal region of Bothrops asper myothoxin II, a Lys49 phospholipase A(2) (PLA(2)), were found to reproduce the antimicrobial activities of their parent molecule. Of these peptides, KKWRWWLKALAKK-designated PEM-2-was found to display improved activity against both Gram-positive and Gram-negative bacteria. To improve the antimicrobial activity of PEM-2 for potential clinical applications further, we determined the solution structure of PEM-2 bound to membrane-mimetic dodecylphosphocholine (DPC) micelles by two-dimensional NMR methods. The DPC micelle-bound structure of PEM-2 adopts an α-helical conformation and the positively charged residues are clustered together to form a hydrophilic patch. The surface electrostatic potential map indicates that two of the three tryptophan residues are packed against the peptide backbone and form a hydrophobic face with Leu7, Ala9, and Leu10. A variety of biophysical and biochemical experiments, including circular dichroism, fluorescence spectroscopy, and microcalorimetry, were used to show that PEM-2 interacted with negatively charged phospholipid vesicles and efficiently induced dye release from these vesicles, suggesting that the antimicrobial activity of PEM-2 could be due to interactions with bacterial membranes. Potent analogues of PEM-2 with enhanced antimicrobial and less pronounced hemolytic activities were designed with the aid of these structural studies. PMID:20865718

  6. Antimicrobial Cellobiose Dehydrogenase-Chitosan Particles.

    PubMed

    Tegl, Gregor; Thallinger, Barbara; Beer, Bianca; Sygmund, Christoph; Ludwig, Roland; Rollett, Alexandra; Nyanhongo, Gibson S; Guebitz, Georg M

    2016-01-13

    Increasing prevalence of chronic wounds and microbial infection constitute a severe health challenge. The situation is further complicated by emerging multidrug resistance making the treatment of infections increasingly difficult. Here, a novel antimicrobial system based on in situ release of hydrogen peroxide (H2O2) by cellobiose dehydrogenase (CDH) immobilized on chitosan (CTS) particles is described. Covalent immobilization using carbodiimide coupling lead to a higher amount of protein immobilized on CTS (104 μg CDH/mg CTS) when compared to noncovalent immobilization, which, however, showed highest recovery of CDH activity (0.01 U/mg CTS). The CDH-CTS in situ generated H2O2 completely inhibited growth of Escherichia coli and Staphylococcus aureus over a period of 24 h. This resilient antimicrobial system represents a novel strategy for preventing infection with potential application in counteracting microbial colonization of chronic wounds. PMID:26672396

  7. Design and Application of Antimicrobial Peptide Conjugates.

    PubMed

    Reinhardt, Andre; Neundorf, Ines

    2016-01-01

    Antimicrobial peptides (AMPs) are an interesting class of antibiotics characterized by their unique antibiotic activity and lower propensity for developing resistance compared to common antibiotics. They belong to the class of membrane-active peptides and usually act selectively against bacteria, fungi and protozoans. AMPs, but also peptide conjugates containing AMPs, have come more and more into the focus of research during the last few years. Within this article, recent work on AMP conjugates is reviewed. Different aspects will be highlighted as a combination of AMPs with antibiotics or organometallic compounds aiming to increase antibacterial activity or target selectivity, conjugation with photosensitizers for improving photodynamic therapy (PDT) or the attachment to particles, to name only a few. Owing to the enormous resonance of antimicrobial conjugates in the literature so far, this research topic seems to be very attractive to different scientific fields, like medicine, biology, biochemistry or chemistry. PMID:27187357

  8. Mechanisms of biofilm resistance to antimicrobial agents.

    PubMed

    Mah, T F; O'Toole, G A

    2001-01-01

    Biofilms are communities of microorganisms attached to a surface. It has become clear that biofilm-grown cells express properties distinct from planktonic cells, one of which is an increased resistance to antimicrobial agents. Recent work has indicated that slow growth and/or induction of an rpoS-mediated stress response could contribute to biocide resistance. The physical and/or chemical structure of exopolysaccharides or other aspects of biofilm architecture could also confer resistance by exclusion of biocides from the bacterial community. Finally, biofilm-grown bacteria might develop a biofilm-specific biocide-resistant phenotype. Owing to the heterogeneous nature of the biofilm, it is likely that there are multiple resistance mechanisms at work within a single community. Recent research has begun to shed light on how and why surface-attached microbial communities develop resistance to antimicrobial agents. PMID:11166241

  9. Leaves Antimicrobial Activity of Glycyrrhiza glabra L.

    PubMed

    Irani, Mahboubeh; Sarmadi, Marziyeh; Bernard, Françoise; Ebrahimi Pour, Gholam Hossein; Shaker Bazarnov, Hossein

    2010-01-01

    Licorice (Glycyrrhiza glabra L.) is an important medicinal plant. In this study, the antimicrobial activities of ethanolic and aqueous extracts from licorice leaves were studied compared to root extracts activities. Bacillus subtilis, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli, and Candida albicans were used as test organisms. Antimicrobial activity was tested by paper disc agar diffusion and serial dilution methods in order to determine minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The root and leave extracts showed activity against Candida albicans, and tested gram-positive bacteria in a dose dependent manner. The ethanolic extract of the leaves was the most active extract against gram-positive bacteria. Its effectiveness against strains provides hope that it can serve as an alternative therapeutic agent. PMID:24381608

  10. Antimicrobial therapy in patients with septic shock.

    PubMed

    Pastene, Bruno; Duclos, Gary; Martin, Claude; Leone, Marc

    2016-04-01

    Providing antibiotics is a life-saving intervention in patients with septic shock. Cultures as clinically appropriate before antimicrobial therapy are required. Guidelines recommend providing broad-spectrum antibiotics within the first hour after recognition of shock. The site of infection, the patient's history and clinical status, and the local ecology all affect the choice of empirical treatment. The appropriateness of this choice is an important determinant of patient outcome. At 48-96h, the antimicrobial treatment should be systematically reassessed based on the clinical course and culture results. Cessation, de-escalation, continuation, or escalation are discussed according to these variables. Unnecessary treatment should be avoided to reduce the emergence of multidrug resistant pathogens. PMID:27062114

  11. Biocompatible 3D Matrix with Antimicrobial Properties.

    PubMed

    Ion, Alberto; Andronescu, Ecaterina; Rădulescu, Dragoș; Rădulescu, Marius; Iordache, Florin; Vasile, Bogdan Ștefan; Surdu, Adrian Vasile; Albu, Madalina Georgiana; Maniu, Horia; Chifiriuc, Mariana Carmen; Grumezescu, Alexandru Mihai; Holban, Alina Maria

    2016-01-01

    The aim of this study was to develop, characterize and assess the biological activity of a new regenerative 3D matrix with antimicrobial properties, based on collagen (COLL), hydroxyapatite (HAp), β-cyclodextrin (β-CD) and usnic acid (UA). The prepared 3D matrix was characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Microscopy (FT-IRM), Transmission Electron Microscopy (TEM), and X-ray Diffraction (XRD). In vitro qualitative and quantitative analyses performed on cultured diploid cells demonstrated that the 3D matrix is biocompatible, allowing the normal development and growth of MG-63 osteoblast-like cells and exhibited an antimicrobial effect, especially on the Staphylococcus aureus strain, explained by the particular higher inhibitory activity of usnic acid (UA) against Gram positive bacterial strains. Our data strongly recommend the obtained 3D matrix to be used as a successful alternative for the fabrication of three dimensional (3D) anti-infective regeneration matrix for bone tissue engineering. PMID:26805790

  12. Irreversible hydrocolloids: a comparison of antimicrobial efficacy.

    PubMed

    Cserna, A; Crist, R L; Adams, A B; Dunning, D G

    1994-04-01

    The surface antimicrobial efficacy of four irreversible hydrocolloid materials against two common oral bacteria, Lactobacillus and Streptococcus mutans, was evaluated. Twelve reversible hydrocolloid (agar) plates for each bacteria were used. Five wells, 1 cm in diameter by 5 ml in depth, were punched into each plate that contained a known concentration of bacteria. An equal-sized but different type of irreversible hydrocolloid plug was placed into each of four wells. The fifth (center) well contained chlorhexidine (Peridex) as a positive control agent. Results indicated that the irreversible hydrocolloids Coe Hydrophilic Gel (CHG) with chlorhexidine and Jeltrate Plus with quaternary ammonium were both as effective as the positive control agent in reducing surface growth of the bacteria studied. The use of antimicrobial irreversible hydrocolloids thus may aid in reducing operatory to laboratory cross-contamination. PMID:8196004

  13. New antimicrobial molecules and new antibiotic strategies.

    PubMed

    Rodríguez de Castro, Felipe; Naranjo, Olga Rajas; Marco, Javier Aspa; Violán, Jordi Solé

    2009-04-01

    Drug options for treatment of infections are increasingly limited. The pharmaceutical industry has found it difficult to discover new antimicrobial agents, and only two novel classes of antibiotics, the oxazolidinones and the cyclic lipopeptides, have entered the market since the late 1960s. Few new agents have reached the market in the last decade with potential interest for community-acquired pneumonia (CAP) treatment, including linezolid (the first oxazolidinone in clinical use), new fluoroquinolones, cefditoren, ertapenem, and telithromycin. Agents currently in clinical development include other novel quinolones and ketolides, broad-spectrum cephalosporin derivatives, faropenem, several glycopeptides, and iclaprim. Other molecules are considered to be promising candidates for the future. In addition to the foregoing agents, alternative treatment approaches have also been introduced into clinical practice, which include the administration of the appropriate antimicrobials in a timely manner and the consideration of the pharmacokinetic-pharmacodynamic properties of the agent(s). PMID:19296416

  14. Antimicrobial proteins: From old proteins, new tricks.

    PubMed

    Smith, Valerie J; Dyrynda, Elisabeth A

    2015-12-01

    This review describes the main types of antimicrobial peptides (AMPs) synthesised by crustaceans, primarily those identified in shrimp, crayfish, crab and lobster. It includes an overview of their range of microbicidal activities and the current landscape of our understanding of their gene expression patterns in different body tissues. It further summarises how their expression might change following various types of immune challenges. The review further considers proteins or protein fragments from crustaceans that have antimicrobial properties but are more usually associated with other biological functions, or are derived from such proteins. It discusses how these unconventional AMPs might be generated at, or delivered to, sites of infection and how they might contribute to crustacean host defence in vivo. It also highlights recent work that is starting to reveal the extent of multi-functionality displayed by some decapod AMPs, particularly their participation in other aspects of host protection. Examples of such activities include proteinase inhibition, phagocytosis, antiviral activity and haematopoiesis. PMID:26320628

  15. [Antimicrobial activity of orthodontic band cements].

    PubMed

    Pavic, J; Arriagada, M; Elgueta, J; García, C

    1990-01-01

    The prevalence of enamel decalcification and caries beneath orthodontic bands, has indicated the need for a new enamel binding adhesive orthodontic cement. The purpose of this study was to evaluate the antimicrobial activity, in vitro, on Streptococcus mutans and Lactobacillus, acidophillus, of three materials used to cements the orthodontic bands. The cements studied were: Zinc phosphate cement, Glass-ionomer cement, and Policarboxylate cement. Thirty petri plates were seeded with S. mutans, and thirty with L. acidophillus; on each plate three pellet were placed, one of each cement studied. Petri plates were incubated under microaerophilic conditions at 37 C, and checked at 72 hrs. for Streptococcus, mutans, and four days for Lactobacillus acidophillus to evaluate the inhibition zone. The results were tabulated for each material. It was demonstrated that exists important variations in the antimicrobial properties of the materials studied, as in the microbial sensitivity to these cements. PMID:2135908

  16. Measuring the impact of antimicrobial stewardship programs.

    PubMed

    Dik, Jan-Willem H; Hendrix, Ron; Poelman, Randy; Niesters, Hubert G; Postma, Maarten J; Sinha, Bhanu; Friedrich, Alexander W

    2016-06-01

    Antimicrobial Stewardship Programs (ASPs) are being implemented worldwide to optimize antimicrobial therapy, and thereby improve patient safety and quality of care. Additionally, this should counteract resistance development. It is, however, vital that correct and timely diagnostics are performed in parallel, and that an institution runs a well-organized infection prevention program. Currently, there is no clear consensus on which interventions an ASP should comprise. Indeed this depends on the institution, the region, and the patient population that is served. Different interventions will lead to different effects. Therefore, adequate evaluations, both clinically and financially, are crucial. Here, we provide a general overview of, and perspective on different intervention strategies and methods to evaluate these ASP programs, covering before mentioned topics. This should lead to a more consistent approach in evaluating these programs, making it easier to compare different interventions and studies with each other and ultimately improve infection and patient management. PMID:27077229

  17. Antimicrobial activity of Aspilia latissima (Asteraceae)

    PubMed Central

    Souza, Jeana M.E.; Chang, Marilene R.; Brito, Daniela Z.; Farias, Katyuce S.; Damasceno-Junior, Geraldo A.; Turatti, Izabel C.C.; Lopes, Norberto P.; Santos, Edson A.; Carollo, Carlos A.

    2015-01-01

    Abstract We evaluated the antimicrobial activity of Aspilia latissima - an abundant plant from the Brazilian Pantanal region - against Candida albicans, Candida parapsilosis, Candida krusei, Candida tropicalis, Pseudomonas aeruginosa, Enterococcus faecalis, Escherichia coli and Staphylococcus aureus. The crude extracts and fractions showed activity in all tested microorganisms. The chloroform fraction of the leaves and roots showed the most antimicrobial activity against S. aureus, with an MIC of 500 μg/mL. This fraction was submitted to bioautographic assays to characterize the activity of the compounds. Two bands from the leaves (L-A and L-B) and three bands from the roots (R-C, R-D and R-E) were bioactive. Within the root-derived bands, the terpene derivatives stigmasterol, kaurenoic acid and kaura-9(11), 16-dien-18-oic acid were identified. Antibiotic activity of A. latissima is reported for the first time. PMID:26691468

  18. Condensing Heat Exchanger with Hydrophilic Antimicrobial Coating

    NASA Technical Reports Server (NTRS)

    Thomas, Christopher M. (Inventor); Ma, Yonghui (Inventor)

    2014-01-01

    A multi-layer antimicrobial hydrophilic coating is applied to a substrate of anodized aluminum, although other materials may form the substrate. A silver layer is sputtered onto a thoroughly clean anodized surface of the aluminum to about 400 nm thickness. A layer of crosslinked, silicon-based macromolecular structure about 10 nm thickness overlies the silver layer, and the outermost surface of the layer of crosslinked, silicon-based macromolecular structure is hydroxide terminated to produce a hydrophilic surface with a water drop contact angle of less than 10.degree.. The coated substrate may be one of multiple fins in a condensing heat exchanger for use in the microgravity of space, which has narrow channels defined between angled fins such that the surface tension of condensed water moves water by capillary flow to a central location where it is pumped to storage. The antimicrobial coating prevents obstruction of the capillary passages.

  19. Assessing the antimicrobial activities of Ocins.

    PubMed

    Choyam, Shilja; Lokesh, Dhanashree; Kempaiah, Bettadaiah Bheemakere; Kammara, Rajagopal

    2015-01-01

    The generation of a zone of inhibition on a solid substrate indicates the bioactivity of antimicrobial peptides such as bacteriocin and enterocin. The indicator strain plays a significant role in bacteriocin assays. Other characteristics of bacteriocins, such as their dispersal ability and the different zymogram components, also affect bacteriocin assays. However, universal well diffusion assays for antimicrobials, irrespective of their ability to diffuse (bacteriocin and enterocin), do not exist. The ability of different zymography components to generate non-specific activities have rarely been explored in the literature. The purpose of the present work was to evaluate the impact of major factors (diffusion and rate of diffusion) in a solid substrate bioassay, and to document the adverse effects of sodium dodecyl sulfate in zymograms used to estimate the approximate molecular weight of bacteriocins. PMID:26441952

  20. Design and Application of Antimicrobial Peptide Conjugates

    PubMed Central

    Reinhardt, Andre; Neundorf, Ines

    2016-01-01

    Antimicrobial peptides (AMPs) are an interesting class of antibiotics characterized by their unique antibiotic activity and lower propensity for developing resistance compared to common antibiotics. They belong to the class of membrane-active peptides and usually act selectively against bacteria, fungi and protozoans. AMPs, but also peptide conjugates containing AMPs, have come more and more into the focus of research during the last few years. Within this article, recent work on AMP conjugates is reviewed. Different aspects will be highlighted as a combination of AMPs with antibiotics or organometallic compounds aiming to increase antibacterial activity or target selectivity, conjugation with photosensitizers for improving photodynamic therapy (PDT) or the attachment to particles, to name only a few. Owing to the enormous resonance of antimicrobial conjugates in the literature so far, this research topic seems to be very attractive to different scientific fields, like medicine, biology, biochemistry or chemistry. PMID:27187357

  1. Assessing the antimicrobial activities of Ocins

    PubMed Central

    Choyam, Shilja; Lokesh, Dhanashree; Kempaiah, Bettadaiah Bheemakere; Kammara, Rajagopal

    2015-01-01

    The generation of a zone of inhibition on a solid substrate indicates the bioactivity of antimicrobial peptides such as bacteriocin and enterocin. The indicator strain plays a significant role in bacteriocin assays. Other characteristics of bacteriocins, such as their dispersal ability and the different zymogram components, also affect bacteriocin assays. However, universal well diffusion assays for antimicrobials, irrespective of their ability to diffuse (bacteriocin and enterocin), do not exist. The ability of different zymography components to generate non-specific activities have rarely been explored in the literature. The purpose of the present work was to evaluate the impact of major factors (diffusion and rate of diffusion) in a solid substrate bioassay, and to document the adverse effects of sodium dodecyl sulfate in zymograms used to estimate the approximate molecular weight of bacteriocins. PMID:26441952

  2. Antimicrobial activity and chemical composition of some essential oils.

    PubMed

    Aridoğan, Buket Cicioğlu; Baydar, Hasan; Kaya, Selçuk; Demirci, Mustafa; Ozbaşar, Demir; Mumcu, Ethem

    2002-12-01

    In this study the composition and antimicrobial properties of essential oils obtained from Origanum onites, Mentha piperita, Juniperus exalsa, Chrysanthemum indicum, Lavandula hybrida, Rosa damascena, Echinophora tenuifolia, Foeniculum vulgare were examined. To evaluate the in vitro antibacterial activities of these eight aromatic extracts; their in vitro antimicrobial activities were determined by disk diffusion testing, according to the NCCLS criteria. Escherichia coli (ATTC 25922), Staphylococcus aureus (ATCC 25923) and Pseudomonas aeruginosa (ATTC 27853 were used as standard test bacterial strains. Origanum onites recorded antimicrobial activity against all test bacteria, and was strongest against Staphylococcus aureus. For Rosa damascena, Mentha piperita and Lavandula hybrida antimicrobial activity was recorded only to Staphylococcus aureus. Juniperus exalsa, and Chrysanthemum indicum exhibited antibacterial activities against both Staphylococcus aureus and Escherichia coli. We also examined the in vitro antimicrobial activities of some components of the essential oils and found some components with antimicrobial activity. PMID:12510839

  3. Development of chitosan-based antimicrobial leather coatings.

    PubMed

    Fernandes, Isabel P; Amaral, Joana S; Pinto, Vera; Ferreira, Maria José; Barreiro, Maria Filomena

    2013-10-15

    The development of antimicrobial coatings for footwear components is of great interest both from industry and consumer's point of view. In this work, antimicrobial leather materials were developed taking advantage of chitosan intrinsic antimicrobial activity and film forming capacity. Considering the specificities of the leather tanning industry, different coating technologies, namely drum, calender and spray, were tested, being the best results achieved with the drum. This last approach was further investigated to assess the effect of chitosan content, type of solubilizing acid, and impregnation time on the achieved antimicrobial capacity. Considering chitosan price (economic reasons) and the obtained results (antimicrobial activity and coating effectiveness, as inspected by SEM), the impregnation in the drum using a chitosan content of 1% (w/v) in a formic acid solution during 2h, is proposed as the best option for obtaining leather with antimicrobial capacity. PMID:23987468

  4. Curbing the menace of antimicrobial resistance in developing countries

    PubMed Central

    2009-01-01

    Several reports suggest that antimicrobial resistance is an increasing global problem; but like most pandemics, the greatest toll is in the less developed countries. The dismally low rate of discovery of antimicrobials compared to the rate of development of antimicrobial resistance places humanity on a very dangerous precipice. Since antimicrobial resistance is part of an organism's natural survival instinct, total eradication might be unachievable; however, it can be reduced to a level that it no longer poses a threat to humanity. While inappropriate antimicrobial consumption contributes to the development of antimicrobial resistance, other complex political, social, economic and biomedical factors are equally important. Tackling the menace therefore should go beyond the conventional sensitization of members of the public and occasional press releases to include a multi-sectoral intervention involving the formation of various alliances and partnerships. Involving civil society organisations like the media could greatly enhance the success of the interventions PMID:19922676

  5. The changing landscape of antimicrobial resistance in New Zealand.

    PubMed

    Williamson, Deborah A; Heffernan, Helen

    2014-09-26

    Antimicrobial resistance is one of the biggest health threats of the modern age, threatening the routine treatment of many common infectious diseases. Resistance to many common antimicrobials is now endemic in New Zealand, in both community and healthcare settings. Over the past two decades, the landscape of antimicrobial resistance has changed considerably in New Zealand, with the emergence and spread of pathogens such as community-associated methicillin-resistant Staphylococcus aureus, extended-spectrum β-lactamase-producing Enterobacteriaceae and multi- resistant Neisseria gonorrhoeae. Factors contributing to the emergence and spread of antimicrobial-resistant pathogens in New Zealand include the use and overuse of antimicrobials, transmission of resistant organisms in community and healthcare settings, and importation of resistant pathogens from areas where multi-resistant pathogens are endemic. In this review, we provide a summary of major antimicrobial-resistant bacteria in New Zealand, with a specific focus on those pathogens that pose major threats to human health. PMID:25290498

  6. Antimicrobial activity of endophytic fungi isolated from Swietenia macrophylla leaves.

    PubMed

    Ibrahim, Darah; Lee, Chong Chai; Sheh-Hong, Lim

    2014-02-01

    The endophytic fungi isolated from leaves of Swietenia macrophylla of different ages were examined for antimicrobial activity. The agar plug diffusion assay was used for primary screening, followed by the disc diffusion method. A total of 461 filamentous endophytic fungi were isolated and cultured to examine their antimicrobial properties. In the primary screen, 315 isolates (68.3%) exhibited activity against at least one of the test pathogenic microorganisms. The percentage of isolates exhibiting antimicrobial activity increased with leaf age. Endophytic fungal assemblages, as well as those isolates exhibiting antimicrobial properties appeared to increase with leaf age. The main antimicrobial compounds were produced extracellularly by the endophytic fungi. The results suggest that healthy leaves at older stages of growth can be a potential source for the isolation of endophytic fungi with antimicrobial properties. PMID:24689302

  7. Using antimicrobial adjuvant therapy in cancer treatment: a review

    PubMed Central

    2012-01-01

    Recent clinical and pre-clinical data demonstrate that adjuvant antimicrobial therapy is beneficial in cancer treatment. There could be several reasons for this effect, which include treating cancer associated bacteria and viruses, prophylaxis of post-chemotherapy infections due to immunosuppression, and antiproliferative effect of certain antimicrobials. Targeting cancer associated viruses and bacteria with antimicrobial agents is currently used for gastric, cervical, hematopoietic, liver and brain cancer. However this treatment is effective only in combination with conventional therapies. Antimicrobials can also have a direct antiproliferative and cytotoxic effect, and can cause apoptosis. Moreover, some antimicrobials are known to be helpful in overcoming side effects of drugs commonly used in cancer treatment. Chemotherapy related bacteremia and neutropenia can be overcome by the appropriately timed use of antimicrobials. This review summarizes the data on the effects of antivirals and antibiotics on cancer treatment and describes their mechanisms. PMID:23164412

  8. Novel food packaging systems with natural antimicrobial agents.

    PubMed

    Irkin, Reyhan; Esmer, Ozlem Kizilirmak

    2015-10-01

    A new type of packaging that combines food packaging materials with antimicrobial substances to control microbial surface contamination of foods to enhance product microbial safety and to extend shelf-life is attracting interest in the packaging industry. Several antimicrobial compounds can be combined with different types of packaging materials. But in recent years, since consumer demand for natural food ingredients has increased because of safety and availability, these natural compounds are beginning to replace the chemical additives in foods and are perceived to be safer and claimed to alleviate safety concerns. Recent research studies are mainly focused on the application of natural antimicrobials in food packaging system. Biologically derived compounds like bacteriocins, phytochemicals, enzymes can be used in antimicrobial food packaging. The aim of this review is to give an overview of most important knowledge about application of natural antimicrobial packagings with model food systems and their antimicrobial effects on food products. PMID:26396358

  9. Antimicrobial Diterpenoids of Wedelia trilobata (L.) Hitchc.

    PubMed

    Li, Shi-Fei; Ding, Jia-Yin; Li, Ya-Ting; Hao, Xiao-Jiang; Li, Shun-Lin

    2016-01-01

    Continued interest in the metabolites of Wedelia trilobata (L.) Hitchc, a notoriously invasive weed in South China, led to the isolation of twenty-six ent-kaurane diterpenoids, including seven new ones 1-7. Their structures and relative configuration were elucidated on the basis of extensive spectroscopic analysis, including 1D- and 2D-NMR experiments. The antimicrobial activities of all isolated diterpenoids were evaluated against a panel of bacteria and fungi. PMID:27070557

  10. Strategies for antimicrobial drug delivery to biofilm.

    PubMed

    Martin, Claire; Low, Wan Li; Gupta, Abhishek; Amin, Mohd Cairul Iqbal Mohd; Radecka, Iza; Britland, Stephen T; Raj, Prem; Kenward, Ken M A

    2015-01-01

    Biofilms are formed by the attachment of single or mixed microbial communities to a variety of biological and/or synthetic surfaces. Biofilm micro-organisms benefit from many advantages of the polymicrobial environment including increased resistance against antimicrobials and protection against the host organism's defence mechanisms. These benefits stem from a number of structural and physiological differences between planktonic and biofilm-resident microbes, but two main factors are the presence of extracellular polymeric substances (EPS) and quorum sensing communication. Once formed, biofilms begin to synthesise EPS, a complex viscous matrix composed of a variety of macromolecules including proteins, lipids and polysaccharides. In terms of drug delivery strategies, it is the EPS that presents the greatest barrier to diffusion for drug delivery systems and free antimicrobial agents alike. In addition to EPS synthesis, biofilm-based micro-organisms can also produce small, diffusible signalling molecules involved in cell density-dependent intercellular communication, or quorum sensing. Not only does quorum sensing allow microbes to detect critical cell density numbers, but it also permits co-ordinated behaviour within the biofilm, such as iron chelation and defensive antibiotic activities. Against this backdrop of microbial defence and cell density-specific communication, a variety of drug delivery systems have been developed to deliver antimicrobial agents and antibiotics to extracellular and/or intracellular targets, or more recently, to interfere with the specific mechanisms of quorum sensing. Successful delivery strategies have employed lipidic and polymeric-based formulations such as liposomes and cyclodextrins respectively, in addition to inorganic carriers e.g. metal nanoparticles. This review will examine a range of drug delivery systems and their application to biofilm delivery, as well as pharmaceutical formulations with innate antimicrobial properties

  11. Antimicrobial activity of tannins from Terminalia citrina.

    PubMed

    Burapadaja, S; Bunchoo, A

    1995-08-01

    Isolation of the fruit CH3OH extract of Terminalia citrina yielded five known tannins identified as corilagin (1) (3), punicalagin (2) (4), 1,3,6-tri-O-galloyl-beta-D-glucopyranose (3) (5), chebulagic acid (4) (6), and 1,2,3,4,6-penta-O-galloyl-beta-D-glucopyranose (5) (7) by comparison of their physical and spectral data with those of authentic samples. These tannins were tested for antimicrobial action. PMID:7480186

  12. Antimicrobial Peptides Design by Evolutionary Multiobjective Optimization

    PubMed Central

    Maccari, Giuseppe; Di Luca, Mariagrazia; Nifosí, Riccardo; Cardarelli, Francesco; Signore, Giovanni; Boccardi, Claudia; Bifone, Angelo

    2013-01-01

    Antimicrobial peptides (AMPs) are an abundant and wide class of molecules produced by many tissues and cell types in a variety of mammals, plant and animal species. Linear alpha-helical antimicrobial peptides are among the most widespread membrane-disruptive AMPs in nature, representing a particularly successful structural arrangement in innate defense. Recently, AMPs have received increasing attention as potential therapeutic agents, owing to their broad activity spectrum and their reduced tendency to induce resistance. The introduction of non-natural amino acids will be a key requisite in order to contrast host resistance and increase compound's life. In this work, the possibility to design novel AMP sequences with non-natural amino acids was achieved through a flexible computational approach, based on chemophysical profiles of peptide sequences. Quantitative structure-activity relationship (QSAR) descriptors were employed to code each peptide and train two statistical models in order to account for structural and functional properties of alpha-helical amphipathic AMPs. These models were then used as fitness functions for a multi-objective evolutional algorithm, together with a set of constraints for the design of a series of candidate AMPs. Two ab-initio natural peptides were synthesized and experimentally validated for antimicrobial activity, together with a series of control peptides. Furthermore, a well-known Cecropin-Mellitin alpha helical antimicrobial hybrid (CM18) was optimized by shortening its amino acid sequence while maintaining its activity and a peptide with non-natural amino acids was designed and tested, demonstrating the higher activity achievable with artificial residues. PMID:24039565

  13. The antimicrobial efficiency of silver activated sorbents

    NASA Astrophysics Data System (ADS)

    Đolić, Maja B.; Rajaković-Ognjanović, Vladana N.; Štrbac, Svetlana B.; Rakočević, Zlatko Lj.; Veljović, Đorđe N.; Dimitrijević, Suzana I.; Rajaković, Ljubinka V.

    2015-12-01

    This study is focused on the surface modifications of the materials that are used for antimicrobial water treatment. Sorbents of different origin were activated by Ag+-ions. The selection of the most appropriate materials and the most effective activation agents was done according to the results of the sorption and desorption kinetic studies. Sorption capacities of selected sorbents: granulated activated carbon (GAC), zeolite (Z), and titanium dioxide (T), activated by Ag+-ions were following: 42.06, 13.51 and 17.53 mg/g, respectively. The antimicrobial activity of Ag/Z, Ag/GAC and Ag/T sorbents were tested against Gram-negative bacteria E. coli, Gram-positive bacteria S. aureus and yeast C. albicans. After 15 min of exposure period, the highest cell removal was obtained using Ag/Z against S. aureus and E. coli, 98.8 and 93.5%, respectively. Yeast cell inactivation was unsatisfactory for all three activated sorbents. The antimicrobial pathway of the activated sorbents has been examined by two separate tests - Ag+-ions desorbed from the activated surface to the aqueous phase and microbial cell removal caused by the Ag+-ions from the solid phase (activated surface sites). The results indicated that disinfection process significantly depended on the microbial-activated sites interactions on the modified surface. The chemical state of the activating agent had crucial impact to the inhibition rate. The characterization of the native and modified sorbents was performed by X-ray diffraction technique, X-ray photoelectron spectroscopy and scanning electron microscope. The concentration of adsorbed and released ions was determined by inductively coupled plasma optical emission spectroscopy and mass spectrometry. The antimicrobial efficiency of activated sorbents was related not only to the concentration of the activating agent, but moreover on the surface characteristics of the material, which affects the distribution and the accessibility of the activating agent.

  14. Antimicrobial prophylaxis in minor and major surgery.

    PubMed

    Bassetti, M; Righi, E; Astilean, A; Corcione, S; Petrolo, A; Farina, E C; De Rosa, F G

    2015-01-01

    Surgical site infections (SSIs) are a frequent cause of morbidity following surgical procedures. Gram-positive cocci, particularly staphylococci, cause many of these infections, although Gram-negative organisms are also frequently involved. The risk of developing a SSI is associated with a number of factors, including aspects of the operative procedure itself, such as wound classification, and patient-related variables, such as preexisting medical conditions. Antimicrobial prophylaxis (AP) plays an important role in reducing SSIs, especially if patient-related risk factors for SSIs are present. The main components of antimicrobial prophylaxis are: timing, selection of drugs and patients, duration and costs. Compliance with these generally accepted preventive principles may lead to overall decreases in the incidence of these infections. Ideally the administration of the prophylactic agent should start within 30 minutes from the surgical incision. The duration of the AP should not exceed 24 hours for the majority of surgical procedures. The shortest effective period of prophylactic antimicrobial administration is not known and studies have demonstrated that post-surgical antibiotic administration is unnecessary. Furthermore, there were no proven benefits in multiple dose regimens when compared to single-dose regimens. The choice of an appropriate prophylactic antimicrobial agent should be based primarily on efficacy and safety. Broad spectrum antibiotics should be avoided due to the risk of promoting bacterial resistance. Cephalosporins are the most commonly used antibiotics in surgical prophylaxis; specifically, cefazolin or cefuroxime are mainly used in the prophylaxis regimens for cardio-thoracic surgery, vascular surgery, hip or knee arthroplasty surgery, neurosurgical procedures and gynecologic and obstetric procedures. A review of the prophylactic regimens regarding the main surgical procedures is presented. PMID:24561611

  15. Antimicrobial Cu-bearing stainless steel scaffolds.

    PubMed

    Wang, Qiang; Ren, Ling; Li, Xiaopeng; Zhang, Shuyuan; Sercombe, Timothy B; Yang, Ke

    2016-11-01

    Copper-bearing stainless steel scaffolds with two different structures (Body Centered Cubic and Gyroid labyrinth) at two solid fractions (25% and 40%) were fabricated from both 316L powder and a mixture of 316L and elemental Cu powder using selective laser melting, and relative 316L scaffolds were served as control group. After processing, the antimicrobial testing demonstrated that the 316L-Cu scaffolds presented excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus, and the cell viability assay indicated that there was no cytotoxic effect of 316L-Cu scaffolds on rat marrow mesenchymal stem cells. As such, these have the potential to reduce implant-associated infections. The Cu was also found to homogeneously distribute within the microstructure by scanning electronic microcopy. The addition of Cu would not significantly affect its strength and stiffness compared to 316L scaffold, and the stiffness of all the scaffolds (3-20GPa) is similar to that of bone and much less than that of bulk stainless steel. Consequently, fabrication of such low stiffness porous structures, especially coupled with the addition of antimicrobial Cu, may provide a new direction for medical stainless steels. PMID:27524049

  16. Antianaerobic Antimicrobials: Spectrum and Susceptibility Testing

    PubMed Central

    Wexler, Hannah M.; Goldstein, Ellie J. C.

    2013-01-01

    SUMMARY Susceptibility testing of anaerobic bacteria recovered from selected cases can influence the choice of antimicrobial therapy. The Clinical and Laboratory Standards Institute (CLSI) has standardized many laboratory procedures, including anaerobic susceptibility testing (AST), and has published documents for AST. The standardization of testing methods by the CLSI allows comparisons of resistance trends among various laboratories. Susceptibility testing should be performed on organisms recovered from sterile body sites, those that are isolated in pure culture, or those that are clinically important and have variable or unique susceptibility patterns. Organisms that should be considered for individual isolate testing include highly virulent pathogens for which susceptibility cannot be predicted, such as Bacteroides, Prevotella, Fusobacterium, and Clostridium spp.; Bilophila wadsworthia; and Sutterella wadsworthensis. This review describes the current methods for AST in research and reference laboratories. These methods include the use of agar dilution, broth microdilution, Etest, and the spiral gradient endpoint system. The antimicrobials potentially effective against anaerobic bacteria include beta-lactams, combinations of beta-lactams and beta-lactamase inhibitors, metronidazole, chloramphenicol, clindamycin, macrolides, tetracyclines, and fluoroquinolones. The spectrum of efficacy, antimicrobial resistance mechanisms, and resistance patterns against these agents are described. PMID:23824372

  17. Diversity of wheat anti-microbial peptides.

    PubMed

    Egorov, Tsezi A; Odintsova, Tatyana I; Pukhalsky, Vitaliy A; Grishin, Eugene V

    2005-11-01

    From seeds of Triticum kiharae Dorof. et Migusch., 24 novel anti-microbial peptides were isolated and characterized by a combination of three-step HPLC (affinity, size-exclusion and reversed-phase) with matrix-assisted laser-desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and Edman degradation. Based on sequence similarity and cysteine motifs, partially sequenced peptides were assigned to 7 families: defensins, thionins, lipid-transfer proteins, hevein-like peptides, knottin-like peptides, glycine-rich peptides, and MBP-1 homologs. A novel subfamily of defensins consisting of 6 peptides and a new family of glycine-rich (8 peptides with different repeat motifs) were identified. Three 6-cysteine knottin-like peptides represented by N- and C-terminally truncated variants revealed no sequence homology to any known plant anti-microbial peptides. A new 8-cysteine hevein-like peptide and three 4-cysteine peptides homologous to MBP-1 from maize were isolated. This is the first communication on the occurrence of nearly all families of plant anti-microbial peptides in a single species. PMID:16269343

  18. Toxicology of antimicrobial nanoparticles for prosthetic devices

    PubMed Central

    Nuñez-Anita, Rosa Elvira; Acosta-Torres, Laura Susana; Vilar-Pineda, Jorge; Martínez-Espinosa, Juan Carlos; de la Fuente-Hernández, Javier; Castaño, Víctor Manuel

    2014-01-01

    Advances in nanotechnology are producing an accelerated proliferation of new nanomaterial composites that are likely to become an important source of engineered health-related products. Nanoparticles with antifungal effects are of great interest in the formulation of microbicidal materials. Fungi are found as innocuous commensals and colonize various habitats in and on humans, especially the skin and mucosa. As growth on surfaces is a natural part of the Candida spp. lifestyle, one can expect that Candida organisms colonize prosthetic devices, such as dentures. Macromolecular systems, due to their properties, allow efficient use of these materials in various fields, including the creation of reinforced nanoparticle polymers with antimicrobial activity. This review briefly summarizes the results of studies conducted during the past decade and especially in the last few years focused on the toxicity of different antimicrobial polymers and factors influencing their activities, as well as the main applications of antimicrobial polymers in dentistry. The present study addresses aspects that are often overlooked in nanotoxicology studies, such as careful time-dependent characterization of agglomeration and ion release. PMID:25187703

  19. Topical antimicrobial toolkit for wound infection.

    PubMed

    Woo, Kevin Y; Alam, Tarik; Marin, Joseph

    2014-11-01

    Increased bacterial burden and formation of biofilm has been recognized as one of the key factors contributing to delayed wound healing. There is a toolbox of topical antimicrobial wound dressings that incorporate silver, iodine, polyhexamethylene biguanide, methylene blue/gentian violet, and honey. This article reviews a diverse range of evidence to discuss the advantages and disadvantage of topical antimicrobial dressings. Discussion will provide guidance on when and how to use topical antimicrobial dressings to achieve optimal outcomes and cost-effective wound care. Chronic wounds do not follow a predictable and expected healing trajectory, and they may persist for months or years due to underlying disease processes, recurrent injury, and comorbidities.1 With an aging population and increased prevalence of chronic diseases, the majority of wounds are refractory to healing, placing a significant burden on the health system and individual patients. Bacterial burden and biofilm have been recognized as key factors contributing to persistent inflammation, tissue destruction, delayed wound healing, and other serious complications (especially in individuals who are frail and immune-compromised).2 It has been demonstrated that when bacterial growth reaches a critical threshold of 105 bacteria per gram of tissue, bacterial toxins can cause tissue damage in the superficial wound compartment, delaying healing.2 In the literature, this phenomenon is referred to as critical colonization, increased bacterial burden, superficial infection, or localized infection. According to a recent review, over 50% of chronic wounds exhibit signs and symptoms that are consistent with localized infection.3. PMID:25433174

  20. ANTIMICROBIAL ACTIVITY OF EXTRACTS FROM ECUADORIAN LICHENS.

    PubMed

    Matvieieva, N A; Pasichnyk, L A; Zhytkevych, N V; Jacinto, Pabón Garcés Galo; Pidgorskyi, V S

    2015-01-01

    Antimicrobial activity of the ethanolic, isopropanolic, acetone, DMSO and aqueous extracts of the two lichen species from Ecuadorian highland, Usnea sp. and Stereocaulon sp. were explored in vitro against bacteria Bacillus subtilis, Escherichia coli and Staphylococcus aureus by the disc-diffusion method. Also the minimal inhibitory concentration (MIC) was determined. The strongest antimicrobial activity was found in DMSO extract of Usnea sp. compared to antibacterial activity of ciprfloxacin and cefazolin antibiotics. The inhibition zone was 28 mm, 30 mm, 31mm (DMSO extract, ciprfloxacin and cefazolin respectively) in case of B. subtilis usage as the test bacteria. MIC value for Usnea sp. and Stereocaulon sp. DMSO extracts was 0.4 mg/ml. E. coli was resistant to all kinds of extracts. The S. aureus sensitivity to lichen DMSO extracts was comparable to sensitivity of these microorganisms to tetracycline and vancomycin. Thereby, most kinds of extracts (ethanol, isopropanol, hexane, DMSO and acetone solvents) from Ecuadorian lichens Usnea sp. and Stereocaulon sp. with the exception of aqueous Stereocaulon sp. extracts possessed antibacterial activity against B. subtilis. DMSO lichen extracts had also antimicrobial activity against S. aureus. At the same time the extracts studied didn't demonstrate antibacterial activity against the representatives of the most common and harmful phytopathogenic bacteria tested. Further investigations of Ecuadorian lichens especially study of plants collected from extremal highland biotops can be very important in study of possibility of treatment of numerous diseases caused by pathogenic microorganisms. PMID:26214895

  1. Antimicrobial peptides: Old Molecules with New Ideas

    PubMed Central

    Nakatsuji, Teruaki; Gallo, Richard L.

    2011-01-01

    Almost 90 years have passed since Alexander Fleming discovered the antimicrobial activity of lysozyme, the first natural antibiotic isolated from our body. Since then, various types of molecules with antibiotic activity have been isolated from animals, insects, plants and bacteria, and their use has revolutionised clinical medicine. So far, more than 1200 types of peptides with antimicrobial activity have been isolated from various cells and tissues, and it appears all living organisms employ these antimicrobial peptides (AMPs) in their host defense. In the last decade, innate AMPs produced by mammals have been shown to be essential for the protection of skin and other organs. Their importance is due to their pleiotrophic functions to not only kill microbes but also control host physiological functions such as inflammation, angiogenesis and wound healing. Recent advances in our understanding of the function of AMPs have associated their altered production with various human diseases such as psoriasis, atopic dermatitis and rosacea. In this review, we summarize the history of AMP biology and provide an overview of recent research progress in this field. PMID:22158560

  2. Effectiveness of antimicrobial food packaging materials.

    PubMed

    Cooksey, K

    2005-10-01

    Antimicrobial additives have been used successfully for many years as direct food additives. The literature provides evidence that some of these additives may be effective as indirect food additives incorporated into food packaging materials. Antimicrobial food packaging is directed toward the reduction of surface contamination of processed, prepared foods such as sliced meats and Frankfurter sausages (hot dogs). The use of such packaging materials is not meant to be a substitute for good sanitation practices, but it should enhance the safety of food as an additional hurdle for the growth of pathogenic and/or spoilage microorganisms. Studies have focused on establishing methods for coating low-density polyethylene film or barrier films with methyl cellulose as a carrier for nisin. These films have significantly reduced the presence of Listeria monocytogenes in solutions and in vacuum packaged hot dogs. Other research has focused on the use of chitosan to inhibit L. monocytogenes and chlorine dioxide sachets for the reduction of Salmonella on modified atmosphere-packaged fresh chicken breasts. Overall, antimicrobial packaging shows promise as an effective method for the inhibition of certain bacteria in foods, but barriers to their commercial implementation continue to exist. PMID:16227182

  3. [New antimicrobials against Gram-positive organisms].

    PubMed

    Montejo, M

    2008-01-01

    Glycopeptides have been the antimicrobials most commonly used for infections by Gram-positive organisms and methicillin resistant S. aureus (MRSA). In recent years, however, glycopeptide resistance and tolerance have become a serious problem. Thus, enterococci highly resistant to vancomycin, vancomycin-intermediate/ resistant S. aureus (VISA), and vancomycin tolerance in S. aureus are found, and increased therapeutic failure and mortality are clinically reported with vancomycin MIC for S. aureus > or = 1.5-2 microg/mL. When faced with these organisms, we therefore need potent bactericidal antimicrobials that may be empirically administered, effective against susceptible and resistant pathogens, easily dosed, with few adverse effects and no significant interaction with other drugs, and that can be administered in an outpatient setting. In bacteremia by methicillin-susceptible S. aureus, use of vancomycin is associated to a greater failure and mortality rate as compared to semisynthetic penicillins. New treatment options for MRSA infections include daptomycin, linezolid, tygecycline, and quinupristin/dalfopristin. New anti-MRSA drugs are also under development, including glycopeptides (dalbavancin, telavancin, and oritavancin), ceftobiprole, and iclaprim. This paper reviews the new antimicrobials against Gram-positive organisms. PMID:18957022

  4. Towards an antimicrobial ‘microglove’

    PubMed Central

    Reilman, Ewoud; Hagting, Joke G.; Flipsen, Theo; Ulmer, Herb; van Dijl, Jan Maarten

    2015-01-01

    A large proportion of hospital-related infections are acquired and spread due to the direct contacts between patients and healthcare workers. Accordingly, proper infection prevention measures, and especially hand hygiene, are key to limit the spread of infections in nosocomial settings. However, healthcare workers frequently experience difficulties in complying strictly to hand disinfection protocols. This study was therefore aimed at the development of a hand rub with antimicrobial activity that forms a protective film on the hand, a so-called microglove, in order to enhance hand hygiene. For this purpose, various co-polymer formulations consisting of different ratios of Polyvinylpyrrolidone (PVP) and a branched C20 derivatized maleate (M20) in combination with the known biocide benzalkonium chloride (BKC) were tested for their combined film-forming and antimicrobial activities. The results of a series of novel contamination and transmission assays show that a formulation of 80% PVP and 20% M20 co-polymer with 0.9% BKC fulfils the elementary requirements for an antimicrobial microglove. PMID:26564815

  5. Antimicrobial activity of garlic against oral streptococci.

    PubMed

    Groppo, F C; Ramacciato, J C; Motta, R H L; Ferraresi, P M; Sartoratto, A

    2007-05-01

    The antimicrobial activity of two garlic clones' (1: purple and 2: white) crude extracts against oral microbiota was evaluated in vitro (study 1) and in vivo (study 2). Study 1 consisted of the evaluation of minimum inhibitory (MIC) and bactericidal (MBC) concentrations against nine streptococci strains. In study 2, a 2.5% garlic (clone 2) solution was used as a mouthwash in a 5-week study by 30 subjects. Blood agar and Mitis Salivarius Bacitracin agar were inoculated with subjects' saliva to quantify oral microorganisms and mutans streptococci. Study 1 showed MIC ranging from 0.5 to 32.0 mg ml(-1) for clone 2 and from 8 to 64.0 mg ml(-1) for clone 1. MBC ranged from 1.0 to 128.0 mg ml(-1) and from 8.0 to 128.0 mg ml(-1) regarding clones 2 and 1 respectively. Study 2 showed that 2.5% garlic mouthwash solution had good antimicrobial activity against mutans streptococci and oral microorganisms. Maintenance of reduced salivary levels of streptococci was observed after 2 weeks at the end of mouthwash use. Unpleasant taste (100%), halitosis (90%) and nausea (30%) were reported by subjects after the end of the study. It was concluded that the garlic clones have antimicrobial properties in vitro against streptococci and anticariogenic properties against oral microorganism in spite of its adverse effects. PMID:17461963

  6. Periodontal antimicrobials--finding the right solutions.

    PubMed

    Jorgensen, Michael G; Aalam, Alexandre; Slots, Jørgen

    2005-02-01

    Strengthened by promising research data and commercial backing, interest in the field of anti-infective periodontal therapy is rapidly expanding. Management of the periodontal microbiota with antibiotic drugs and antiseptic agents in conjunction with mechanical debridement seems to be more effective than mechanical therapy alone, at least in the treatment of advanced periodontal disease. The choice of a periodontal chemotherapeutic regimen requires an understanding of the usual infecting flora, available antimicrobial agents, and pathogen susceptibility patterns. Systemic administration of combinations of metronidazole and either amoxicillin or ciprofloxacin has been widely used with great success; however the presence of subgingival yeasts and resistant bacteria can be a problem in some periodontitis patients. Valuable antiseptic agents for subgingival application include 10% povidone-iodine for professional use and 0.1-0.5% sodium hypochlorite for patient self-care. These antiseptics have significantly broader spectra of antimicrobial action, are less likely to induce development of resistant bacteria and adverse host reactions, and are considerably less expensive than commercially available antibiotics in controlled release devices. In practice, mechanical debridement combined with subgingival povidone-iodine application in the dental office and sodium hypochlorite irrigation for patient self-care are valuable antimicrobial remedies in the treatment of virtually all types of periodontal disease. Management of moderate to severe periodontitis may require additional systemic antibiotic and/or surgical treatment. PMID:15747646

  7. Antianaerobic antimicrobials: spectrum and susceptibility testing.

    PubMed

    Brook, Itzhak; Wexler, Hannah M; Goldstein, Ellie J C

    2013-07-01

    Susceptibility testing of anaerobic bacteria recovered from selected cases can influence the choice of antimicrobial therapy. The Clinical and Laboratory Standards Institute (CLSI) has standardized many laboratory procedures, including anaerobic susceptibility testing (AST), and has published documents for AST. The standardization of testing methods by the CLSI allows comparisons of resistance trends among various laboratories. Susceptibility testing should be performed on organisms recovered from sterile body sites, those that are isolated in pure culture, or those that are clinically important and have variable or unique susceptibility patterns. Organisms that should be considered for individual isolate testing include highly virulent pathogens for which susceptibility cannot be predicted, such as Bacteroides, Prevotella, Fusobacterium, and Clostridium spp.; Bilophila wadsworthia; and Sutterella wadsworthensis. This review describes the current methods for AST in research and reference laboratories. These methods include the use of agar dilution, broth microdilution, Etest, and the spiral gradient endpoint system. The antimicrobials potentially effective against anaerobic bacteria include beta-lactams, combinations of beta-lactams and beta-lactamase inhibitors, metronidazole, chloramphenicol, clindamycin, macrolides, tetracyclines, and fluoroquinolones. The spectrum of efficacy, antimicrobial resistance mechanisms, and resistance patterns against these agents are described. PMID:23824372

  8. IN-VITRO ANTIMICROBIAL ACTIVITY OF BRONCHOSOL.

    PubMed

    Witkowska-Banaszczak, Ewa; Michalak, Anna; Kędzia, Anna

    2015-01-01

    Bronchosol is a traditional medicinal product in the form of syrup used in cough and impeded expectoration. The active ingredients that it contains include extracts from the herb of thyme, the root of primrose and thymol. It is recommended in disorders of the respiratory tract when expectoration is impeded and secretion of liquid mucus in bronchi is insufficient. Antimicrobial activity of the components of Bronchosol, especially thyme and thymol, has frequently been reported in the literature. To date, there have not been any studies to confirm such activity of Bronchosol, though. The results of our research are the first one to point to the great activity of Bronchosol against microorganisms causing infections of the respiratory tract. It has been demonstrated that this product displayed antimicrobial activity against reference strains as well as strains of anaerobic and aerobic bacteria and fungi isolated from patients. The confirmation of the antimicrobial activity of Bronchosol provides an explanation of its effectiveness in the therapy of the respiratory tract infections. PMID:26642688

  9. Toxicology of antimicrobial nanoparticles for prosthetic devices.

    PubMed

    Nuñez-Anita, Rosa Elvira; Acosta-Torres, Laura Susana; Vilar-Pineda, Jorge; Martínez-Espinosa, Juan Carlos; de la Fuente-Hernández, Javier; Castaño, Víctor Manuel

    2014-01-01

    Advances in nanotechnology are producing an accelerated proliferation of new nanomaterial composites that are likely to become an important source of engineered health-related products. Nanoparticles with antifungal effects are of great interest in the formulation of microbicidal materials. Fungi are found as innocuous commensals and colonize various habitats in and on humans, especially the skin and mucosa. As growth on surfaces is a natural part of the Candida spp. lifestyle, one can expect that Candida organisms colonize prosthetic devices, such as dentures. Macromolecular systems, due to their properties, allow efficient use of these materials in various fields, including the creation of reinforced nanoparticle polymers with antimicrobial activity. This review briefly summarizes the results of studies conducted during the past decade and especially in the last few years focused on the toxicity of different antimicrobial polymers and factors influencing their activities, as well as the main applications of antimicrobial polymers in dentistry. The present study addresses aspects that are often overlooked in nanotoxicology studies, such as careful time-dependent characterization of agglomeration and ion release. PMID:25187703

  10. Classification of antimicrobial peptides with imbalanced datasets

    NASA Astrophysics Data System (ADS)

    Camacho, Francy L.; Torres, Rodrigo; Ramos Pollán, Raúl

    2015-12-01

    In the last years, pattern recognition has been applied to several fields for solving multiple problems in science and technology as for example in protein prediction. This methodology can be useful for prediction of activity of biological molecules, e.g. for determination of antimicrobial activity of synthetic and natural peptides. In this work, we evaluate the performance of different physico-chemical properties of peptides (descriptors groups) in the presence of imbalanced data sets, when facing the task of detecting whether a peptide has antimicrobial activity. We evaluate undersampling and class weighting techniques to deal with the class imbalance with different classification methods and descriptor groups. Our classification model showed an estimated precision of 96% showing that descriptors used to codify the amino acid sequences contain enough information to correlate the peptides sequences with their antimicrobial activity by means of learning machines. Moreover, we show how certain descriptor groups (pseudoaminoacid composition type I) work better with imbalanced datasets while others (dipeptide composition) work better with balanced ones.

  11. Antimicrobial activity of preparation Bioaron C.

    PubMed

    Gawron-Gzella, Anne; Michalak, Anna; Kędzia, Anna

    2014-01-01

    The antimicrobial activity of sirupus Bioaron C, a preparation, whose main ingredient is an extract from the leaves of Aloe arborescens, was tested against different microorganisms isolated from patients with upper respiratory tract infections. The experiments were performed on 40 strains: 20 strains of anaerobic bacteria, 13 strains of aerobic bacteria and 7 strains of yeast-like fungi from the genus Candida and on 18 reference strains (ATCC). The antimicrobial activity of Bioaron C (MBC and MFC) was determined at undiluted concentration. Bioaron C proved to be very effective against the microorganisms causing infections. At the concentration recommended by the producer, the preparation showed biocidal activity (MBC, MFC) against the strains of the pathogenic microorganisms, which cause respiratory infections most frequently, including, among others, Peptostreptococcus anaerobius, Parvimonas micra, Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Streptococcus anginosus, Haemophilus influenzae, Moraxella catarrhalis, Pseudomonas aeruginosa and Candida albicans, already after 15 min. The MIC of Bioaron C against most of the tested microorganisms was 5 to 100 times lower than the usually applied concentration. The great antimicrobial activity means that the preparation may be used in the prevention and treatment of infections of the upper respiratory tract. Bioaron C may be an alternative or complement to classical therapy, especially in children. PMID:25362808

  12. Resistance to Antimicrobial Peptides in Vibrios

    PubMed Central

    Destoumieux-Garzón, Delphine; Duperthuy, Marylise; Vanhove, Audrey Sophie; Schmitt, Paulina; Wai, Sun Nyunt

    2014-01-01

    Vibrios are associated with a broad diversity of hosts that produce antimicrobial peptides (AMPs) as part of their defense against microbial infections. In particular, vibrios colonize epithelia, which function as protective barriers and express AMPs as a first line of chemical defense against pathogens. Recent studies have shown they can also colonize phagocytes, key components of the animal immune system. Phagocytes infiltrate infected tissues and use AMPs to kill the phagocytosed microorganisms intracellularly, or deliver their antimicrobial content extracellularly to circumvent tissue infection. We review here the mechanisms by which vibrios have evolved the capacity to evade or resist the potent antimicrobial defenses of the immune cells or tissues they colonize. Among their strategies to resist killing by AMPs, primarily vibrios use membrane remodeling mechanisms. In particular, some highly resistant strains substitute hexaacylated Lipid A with a diglycine residue to reduce their negative surface charge, thereby lowering their electrostatic interactions with cationic AMPs. As a response to envelope stress, which can be induced by membrane-active agents including AMPs, vibrios also release outer membrane vesicles to create a protective membranous shield that traps extracellular AMPs and prevents interaction of the peptides with their own membranes. Finally, once AMPs have breached the bacterial membrane barriers, vibrios use RND efflux pumps, similar to those of other species, to transport AMPs out of their cytoplasmic space. PMID:27025756

  13. Antimicrobial stewardship programme (AMSP) practices in India

    PubMed Central

    Walia, Kamini; Ohri, V.C.; Mathai, Dilip

    2015-01-01

    A survey was conducted to ascertain practice of antimicrobial stewardship programme (AMSP) in India for 2013. A total of 20 health care institutions (HCI) responded to a detailed questionnaire. All the institutions contacted were tertiary care HCI, of which 12 were funded by government (GHCI) and 8 were corporate/private HCI (PHCI). Further, all catered to both rural and urban populations and were spread across the country. Written documents were available with 40 per cent for AMSP, 75 per cent for hospital infection control (HIC) and HIC guidelines and 65 per cent for antimicrobial agents (AMA) prescription guidelines. Records were maintained for health care associated infections (HCAI) by 60 per cent HCI. Antimicrobial resistance (AMR) data were being analysed by 80 per cent HCI. AMA usage data were analysed by only 25 per cent HCI and AMA prescription audit and feedback by 30 per cent. PHCI performed better than GHCI across all fields of AMSP. The main contributory factor was possibly the much higher level of accreditation of PHCI hospitals and their diagnostic laboratories. The absence of infectious diseases physicians and clinical pharmacists is worrying and demands careful attention. PMID:26354210

  14. Guest-Induced Arylamide Polymer Helicity: Twist-Sense Bias and Solvent-Dependent Helicity Inversion.

    PubMed

    Zhang, Peng; Zhang, Liang; Wang, Ze-Kun; Zhang, Yun-Chang; Guo, Rong; Wang, Hui; Zhang, Dan-Wei; Li, Zhan-Ting

    2016-06-01

    A benzene/naphthalene alternately incorporated amide polymer was synthesized and characterized. (1) H NMR spectroscopy, fluorescence, and circular dichroism (CD) experiments indicated that, in chloroform, the polymer could be induced by the chiral l-aspartic acid dianion or one of its derivatives to form a helical tubular conformation with twist-sense bias. CD titration studies showed that the l-aspartic acid dianion (8 equiv.) could lead to a maximum Cotton effect. It was also revealed that the twist-sense bias obeyed the majority rule, and 70 % enantiomeric excess could realize the maximum helicity bias. Adding acetonitrile to the solution of chloroform caused inversion of the guest-induced helicity bias of the polymer. PMID:27027979

  15. Antimicrobial effect of chitosan nanoparticles on streptococcus mutans biofilms.

    PubMed

    Chávez de Paz, Luis E; Resin, Anton; Howard, Kenneth A; Sutherland, Duncan S; Wejse, Peter L

    2011-06-01

    Nanoparticle complexes were prepared from chitosans of various molecular weights (MW) and degrees of deacetylation (DD). The antimicrobial effect was assessed by the Live/Dead BacLight technique in conjunction with confocal scanning laser microscopy (CSLM) and image analysis. Nanocomplexes prepared from chitosans with high MW showed a low antimicrobial effect (20 to 25% of cells damaged), whereas those prepared from low-MW chitosans showed high antimicrobial effect (>95% of cells damaged). PMID:21498764

  16. Antimicrobial Effect of Chitosan Nanoparticles on Streptococcus mutans Biofilms▿

    PubMed Central

    Chávez de Paz, Luis E.; Resin, Anton; Howard, Kenneth A.; Sutherland, Duncan S.; Wejse, Peter L.

    2011-01-01

    Nanoparticle complexes were prepared from chitosans of various molecular weights (MW) and degrees of deacetylation (DD). The antimicrobial effect was assessed by the Live/Dead BacLight technique in conjunction with confocal scanning laser microscopy (CSLM) and image analysis. Nanocomplexes prepared from chitosans with high MW showed a low antimicrobial effect (20 to 25% of cells damaged), whereas those prepared from low-MW chitosans showed high antimicrobial effect (>95% of cells damaged). PMID:21498764

  17. Declines in Outpatient Antimicrobial Use in Canada (1995–2010)

    PubMed Central

    Finley, Rita; Glass-Kaastra, Shiona K.; Hutchinson, Jim; Patrick, David M.; Weiss, Karl; Conly, John

    2013-01-01

    Background With rising reports of antimicrobial resistance in outpatient communities, surveillance of antimicrobial use is imperative for supporting stewardship programs. The primary objective of this article is to assess the levels of antimicrobial use in Canada over time. Methods Canadian antimicrobial use data from 1995 to 2010 were acquired and assessed by four metrics: population-adjusted prescriptions, Defined Daily Doses, spending on antimicrobials (inflation-adjusted), and average Defined Daily Doses per prescription. Linear mixed models were built to assess significant differences among years and antimicrobial groups, and to account for repeated measurements over time. Measures were also compared to published reports from European countries. Results Temporal trends in antimicrobial use in Canada vary by metric and antimicrobial grouping. Overall reductions were seen for inflation-adjusted spending, population-adjusted prescription rates and Defined Daily Doses, and increases were observed for the average number of Defined Daily Doses per prescription. The population-adjusted prescription and Defined Daily Doses values for 2009 were comparable to those reported by many European countries, while the average Defined Daily Dose per prescription for Canada ranked high. A significant reduction in the use of broad spectrum penicillins occurred between 1995 and 2004, coupled with increases in macrolide and quinolone use, suggesting that replacement of antimicrobial drugs may occur as new products arrive on the market. Conclusions There have been modest decreases of antimicrobial use in Canada over the past 15 years. However, continued surveillance of antimicrobial use coupled with data detailing antimicrobial resistance within bacterial pathogens affecting human populations is critical for targeting interventions and maintaining the effectiveness of these products for future generations. PMID:24146863

  18. Antimicrobial Properties of Graphene Oxide Nanosheets: Why Size Matters.

    PubMed

    Perreault, François; de Faria, Andreia Fonseca; Nejati, Siamak; Elimelech, Menachem

    2015-07-28

    Graphene oxide (GO) is a promising material for the development of antimicrobial surfaces due to its contact-based antimicrobial activity. However, the relationship between GO physicochemical properties and its antimicrobial activity has yet to be elucidated. In this study, we investigated the size-dependency of GO antimicrobial activity using the Gram-negative bacteria Escherichia coli. GO suspensions of average sheet area ranging from 0.01 to 0.65 μm(2) were produced and their antimicrobial activity evaluated in cell suspensions or as a model GO surface coating. The antimicrobial activity of GO surface coatings increased 4-fold when GO sheet area decreased from 0.65 to 0.01 μm(2). The higher antimicrobial effect of smaller GO sheets is attributed to oxidative mechanisms associated with the higher defect density of smaller sheets. In contrast, in suspension assays, GO interacted with bacteria in a cell entrapment mechanism; in this case, the antimicrobial effect of GO increased with increasing sheet area, with apparent complete inactivation observed for the 0.65 μm(2) sheets after a 3 h exposure. However, cell inactivation by GO entrapment was reversible and all initially viable cells could be recovered when separated from GO sheets by sonication. These findings provide useful guidelines for future development of graphene-based antimicrobial surface coatings, where smaller sheet sizes can increase the antimicrobial activity of the material. Our study further emphasizes the importance of an accurate assessment of the antimicrobial effect of nanomaterials when used for antimicrobial surface design. PMID:26091689

  19. Update: The National Antimicrobial Resistance Monitoring System Enteric Bacteria (NARMS): Animal Arm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimicrobial susceptibility testing remains an important tool as investigators devise ways to arrest the development of antimicrobial resistance, particularly in food borne bacteria. In 1996, the Food and Drug Administration (FDA) initiated the National Antimicrobial Resistance Monitoring System -...

  20. Overview Of Antimicrobial Resistance In Food Borne Pathogens In The United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimicrobial susceptibility testing remains an important tool as investigators devise ways to arrest the development of antimicrobial resistance, particularly in food borne bacteria. In 1996, the Food and Drug Administration (FDA) initiated the National Antimicrobial Resistance Monitoring System -...

  1. Narrow grass hedges reduce tylosin and associated antimicrobial resistance genes in agricultural runoff

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural runoff from areas receiving livestock manure can potentially contaminate surface water with antimicrobials and antimicrobial resistance genes (ARGs). The objective of this study was to investigate the effectiveness of narrow grass hedges (NGHs) on reducing the transport of antimicrobial...

  2. Characterization and Tracking of Antimicrobial Resistant Pathogens at Various Points along the Poultry Production Chain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antimicrobial susceptibility testing remains an important tool as investigators devise ways to arrest the development of antimicrobial resistance, particularly in food borne bacteria. In 1996, the Food and Drug Administration (FDA) initiated the National Antimicrobial Resistance Monitoring System -...

  3. Antimicrobial Resistance in the Food Chain: A Review

    PubMed Central

    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

  4. Salmon Aquaculture and Antimicrobial Resistance in the Marine Environment

    PubMed Central

    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

  5. Antimicrobial activity of some medicinal plants from Ghana.

    PubMed

    Konning, G H; Agyare, C; Ennison, B

    2004-01-01

    The results of a preliminary antimicrobial screening of the methanol extracts of Aframomum melegueta, Piper guineense, Xylopia aethiopica, Zingiber officinale, medicinal plants of Ghana, are reported. PMID:14693222

  6. Mechanisms of the Antimicrobial Activities of Graphene Materials.

    PubMed

    Zou, Xuefeng; Zhang, Li; Wang, Zhaojun; Luo, Yang

    2016-02-24

    A thorough understanding of the antimicrobial mechanisms of graphene materials (GMs) is critical to the manipulation of highly efficient antimicrobial nanomaterials for future biomedical applications. Here we review the most recent studies of GM-mediated antimicrobial properties. This review covers the physicochemical properties of GMs, experimental surroundings, and selected microorganisms as well as the interaction between GMs and selected microorganisms to explore controversial antimicrobial activities. Finally, we rationally analyze the strengths and weaknesses of the proposed mechanisms and provide new insights into the remaining challenges and perspectives for future studies. PMID:26824139

  7. Antimicrobial activity of some medicinal plants from India.

    PubMed

    Samy, R Perumal

    2005-12-01

    The results of a preliminary antimicrobial screening of the methanol extracts of Zingiber officinale, Asteracantha longifolia, Citrus acida, Salacia microsperma and Tinospora cordifolia are reported. PMID:16229969

  8. Antimicrobial peptides in the centipede Scolopendra subspinipes mutilans.

    PubMed

    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. PMID:24652097

  9. Comparative Evaluation of the Antimicrobial Activity of Different Antimicrobial Peptides against a Range of Pathogenic Bacteria

    PubMed Central

    Ebbensgaard, Anna; Mordhorst, Hanne; Overgaard, Michael Toft; Nielsen, Claus Gyrup; Aarestrup, Frank Møller; Hansen, Egon Bech

    2015-01-01

    Analysis of a Selected Set of Antimicrobial Peptides 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-negative bacteria. We compared the potency of Cap18, Cap11, Cap11-1-18m2, Cecropin P1, Cecropin B, Bac2A, Bac2A-NH2, Sub5-NH2, Indolicidin, Melittin, Myxinidin, Myxinidin-NH2, Pyrrhocoricin, Apidaecin and Metalnikowin I towards Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, Escherichia coli, Aeromonas salmonicida, Listeria monocytogenes, Campylobacter jejuni, Flavobacterium psychrophilum, Salmonella typhimurium and Yersinia ruckeri by minimal inhibitory concentration (MIC) determinations. Additional characteristics such as cytotoxicity, thermo and protease stability were measured and compared among the different peptides. Further, the antimicrobial activity of a selection of cationic AMPs was investigated in various E. coli LPS mutants. Cap18 Shows a High Broad Spectrum Antimicrobial Activity Of all the tested AMPs, Cap18 showed the most efficient antimicrobial activity, in particular against Gram-negative bacteria. In addition, Cap18 is highly thermostable and showed no cytotoxic effect in a hemolytic assay, measured at the concentration used. However, Cap18 is, as most of the tested AMPs, sensitive to proteolytic digestion in vitro. Thus, Cap18 is an excellent candidate for further development into practical use; however, modifications that should reduce the protease sensitivity would be needed. In addition, our

  10. Antimicrobial (Drug) Resistance: Vancomycin-Resistant Enterococci (VRE) Frequently Asked Questions

    MedlinePlus

    ... Understanding Antimicrobial (Drug) Resistance Examples of Antimicrobial Resistance Methicillin-Resistant Staphylococcus aureus (MRSA) Vancomycin-Resistant Enterococci (VRE) Overview Transmission Diagnosis ...

  11. Impulse control and restrained eating among young women: Evidence for compensatory cortical activation during a chocolate-specific delayed discounting task.

    PubMed

    Dong, Debo; Wang, Yulin; Jackson, Todd; Chen, Shuaiyu; Wang, Yu; Zhou, Feng; Chen, Hong

    2016-10-01

    Theory and associated research indicate that people with elevated restrained eating (RE) scores have higher risk for binge eating, future bulimic symptom onset and weight gain. Previous imaging studies have suggested hyper-responsive reward brain area activation in response to food cues contributes to this risk but little is known about associated neural impulse control mechanisms, especially when considering links between depleted cognitive resources related to unsuccessful RE. Towards illuminating this issue, we used a chocolate-specific delayed discounting (DD) task to investigate relations between RE scores, behavior impulsivity, and corresponding neural impulse control correlates in a functional magnetic resonance imaging (fMRI) study of 27 young women. Specifically, participants were required to choose between more immediate, smaller versus delayed, larger hypothetical chocolate rewards following initial consumption of a chocolate. As predicted, RE scores were correlated positively with behavior impulse control levels. More critically, higher RE scores were associated with stronger activation in impulse control region, the dorsal-lateral prefrontal cortex (DLPFC) during the completion of difficult decision trials reflecting higher cognitive demands and resource depletion relative to easy decision trials. Exploratory analyses revealed a positive correlation between RE scores and activity in a reward system hub, the right striatum. Moreover, a positive correlation between left DLPFC and striatum activation was posited to reflect, in part, impulse control region compensation in response to stronger reward signal among women with RE elevations. Findings suggested impulse control lapses may contribute to difficulties in maintaining RE, particularly when cognitive demands are high. PMID:27208593

  12. Escherichia coli Nissle 1917 targets and restrains mouse B16 melanoma and 4T1 breast tumors through expression of azurin protein.

    PubMed

    Zhang, Yunlei; Zhang, Youming; Xia, Liqiu; Zhang, Xiangli; Ding, Xuezhi; Yan, Fu; Wu, Feng

    2012-11-01

    Many studies have demonstrated that intravenously administered bacteria can target and proliferate in solid tumors and then quickly be released from other organs. Here, we employed the tumor-targeting property of Escherichia coli Nissle 1917 to inhibit mouse B16 melanoma and 4T1 breast tumors through the expression of azurin protein. For this purpose, recombinant azurin-expressing E. coli Nissle 1917 was developed. The levels of in vitro and in vivo azurin secretion in the engineered bacterium were determined by immunochemistry. Our results demonstrated that B16 melanoma and orthotopic 4T1 breast tumor growth were remarkably restrained and pulmonary metastasis was prevented in immunocompetent mice. It is worth noting that this therapeutic effect partially resulted from the antitumor activity of neutrophils and lymphocytes due to inflammatory responses caused by bacterial infections. No toxicity was observed in the animal during the experiments. This study indicates that E. coli Nissle 1917 could be a potential carrier to deliver antitumor drugs effectively for cancer therapy. PMID:22923405

  13. The cholesterol-binding protein NPC2 restrains recruitment of stromal macrophage-lineage cells to early-stage lung tumours.

    PubMed

    Kamata, Tamihiro; Jin, Hong; Giblett, Susan; Patel, Bipin; Patel, Falguni; Foster, Charles; Pritchard, Catrin

    2015-09-01

    The tumour microenvironment is known to play an integral role in facilitating cancer progression at advanced stages, but its function in some pre-cancerous lesions remains elusive. We have used the (V600) (E)BRAF-driven mouse lung model that develop premalignant lesions to understand stroma-tumour interactions during pre-cancerous development. In this model, we have found that immature macrophage-lineage cells (IMCs) producing PDGFA, TGFβ and CC chemokines are recruited to the stroma of premalignant lung adenomas through CC chemokine receptor 1 (CCR1)-dependent mechanisms. Stromal IMCs promote proliferation and transcriptional alterations suggestive of epithelial-mesenchymal transition in isolated premalignant lung tumour cells ex vivo, and are required for the maintenance of early-stage lung tumours in vivo. Furthermore, we have found that IMC recruitment to the microenvironment is restrained by the cholesterol-binding protein, Niemann-Pick type C2 (NPC2). Studies on isolated cells ex vivo confirm that NPC2 is secreted from tumour cells and is taken up by IMCs wherein it suppresses secretion of the CCR1 ligand CC chemokine 6 (CCL6), at least in part by facilitating its lysosomal degradation. Together, these findings show that NPC2 secreted by premalignant lung tumours suppresses IMC recruitment to the microenvironment in a paracrine manner, thus identifying a novel target for the development of chemopreventive strategies in lung cancer. PMID:26183450

  14. Capsaicin-Induced Activation of p53-SMAR1 Auto-Regulatory Loop Down-Regulates VEGF in Non-Small Cell Lung Cancer to Restrain Angiogenesis

    PubMed Central

    Chakraborty, Samik; Mukherjee, Shravanti; Bhattacharjee, Pushpak; Guha, Deblina; Choudhuri, Tathagata; Chattopadhyay, Samit; Sa, Gaurisankar; Sen, Aparna; Das, Tanya

    2014-01-01

    Lung cancer is the leading cause of cancer-related deaths worldwide. Despite decades of research, the treatment options for lung cancer patients remain inadequate, either to offer a cure or even a substantial survival advantage owing to its intrinsic resistance to chemotherapy. Our results propose the effectiveness of capsaicin in down-regulating VEGF expression in non-small cell lung carcinoma (NSCLC) cells in hypoxic environment. Capsaicin-treatment re-activated p53-SMAR1 positive feed-back loop in these cells to persuade p53-mediated HIF-1α degradation and SMAR1-induced repression of Cox-2 expression that restrained HIF-1α nuclear localization. Such signal-modulations consequently down regulated VEGF expression to thwart endothelial cell migration and network formation, pre-requisites of angiogenesis in tumor micro-environment. The above results advocate the candidature of capsaicin in exclusively targeting angiogenesis by down-regulating VEGF in tumor cells to achieve more efficient and cogent therapy of resistant NSCLC. PMID:24926985

  15. Huaier restrains proliferative and invasive potential of human hepatoma SKHEP-1 cells partially through decreased Lamin B1 and elevated NOV.

    PubMed

    Hu, Zhongdong; Yang, Ailin; Su, Guozhu; Zhao, Yunfang; Wang, Ying; Chai, Xingyun; Tu, Pengfei

    2016-01-01

    Hepatocellular carcinoma (HCC) is one of the most common cause of malignancy-related mortality worldwide. It is urgently needed to develop potential drugs with good efficacy and low toxicity for HCC treatment. The anti-tumor effect of Traditional Chinese Medicine (TCM) has received increasing attention worldwide. Trametes robiniophila Murr. (Huaier) has been used in TCM for approximately 1,600 years. Clinically, Huaier has satisfactory therapeutic effects in cancer treatment, especially in HCC. However, the mechanisms underlying the anti-cancer effect of Huaier remain ill defined. Herein we have demonstrated that Huaier dramatically inhibited cell proliferation and induced apoptosis in human hepatoma cell line SKHEP-1. Importantly, Huaier restrained the metastatic capability of SKHEP-1 cells. Mechanistically, down-regulation of Lamin B1 and up-regulation of Nephroblastoma overexpressed (NOV) were at least partially responsible for the inhibitory effect of Huaier on the proliferative and invasive capacity of SKHEP-1 cells. Our finding provided new insights into mechanisms of anti-HCC effect of Huaier and suggested a new scientific basis for clinical medication. PMID:27503760

  16. Effects of two cognitive regulation strategies on the processing of food cues in high restrained eaters. An event-related potential study.

    PubMed

    Svaldi, Jennifer; Tuschen-Caffier, Brunna; Biehl, Stefanie C; Gschwendtner, Kathrin; Wolz, Ines; Naumann, Eva

    2015-09-01

    This study tested the effects of cognitive regulation (CR) on the attentional processing of food cues in restrained eaters (RE) by means of event-related potentials (ERPs). In a within-subject-design, RE (n = 23) were presented pictures of highly palatable food and office items while ERPs were recorded. Prior to the presentation of the food stimuli, participants were either instructed to engage in reappraisal or to attempt to suppress cravings - both cognitive regulation (CR) strategies - or to simply watch the pictures. Prior to the presentation of the neutral stimuli, participants were instructed to simply watch them. Following each picture presentation, momentary craving was assessed. Main results showed that engaging in CR significantly reduced ERP amplitudes compared to the food watch condition. Passively attending to food pictures yielded significantly higher craving scores compared to engaging in CR. In addition, craving was significantly lower in the reappraisal than in the suppression condition. Therefore, reappraisal could potentially increase the ability to inhibit the appetitive motivation to eat. PMID:26025088

  17. Escherichia coli Nissle 1917 Targets and Restrains Mouse B16 Melanoma and 4T1 Breast Tumors through Expression of Azurin Protein

    PubMed Central

    Zhang, Yunlei; Zhang, Youming; Zhang, Xiangli; Ding, Xuezhi; Yan, Fu; Wu, Feng

    2012-01-01

    Many studies have demonstrated that intravenously administered bacteria can target and proliferate in solid tumors and then quickly be released from other organs. Here, we employed the tumor-targeting property of Escherichia coli Nissle 1917 to inhibit mouse B16 melanoma and 4T1 breast tumors through the expression of azurin protein. For this purpose, recombinant azurin-expressing E. coli Nissle 1917 was developed. The levels of in vitro and in vivo azurin secretion in the engineered bacterium were determined by immunochemistry. Our results demonstrated that B16 melanoma and orthotopic 4T1 breast tumor growth were remarkably restrained and pulmonary metastasis was prevented in immunocompetent mice. It is worth noting that this therapeutic effect partially resulted from the antitumor activity of neutrophils and lymphocytes due to inflammatory responses caused by bacterial infections. No toxicity was observed in the animal during the experiments. This study indicates that E. coli Nissle 1917 could be a potential carrier to deliver antitumor drugs effectively for cancer therapy. PMID:22923405

  18. Enhanced delivery of etoposide across the blood-brain barrier to restrain brain tumor growth using melanotransferrin antibody- and tamoxifen-conjugated solid lipid nanoparticles.

    PubMed

    Kuo, Yung-Chih; Wang, I-Hsin

    2016-08-01

    Melanotransferrin antibody (MA) and tamoxifen (TX) were conjugated on etoposide (ETP)-entrapped solid lipid nanoparticles (ETP-SLNs) to target the blood-brain barrier (BBB) and glioblastom multiforme (GBM). MA- and TX-conjugated ETP-SLNs (MA-TX-ETP-SLNs) were used to infiltrate the BBB comprising a monolayer of human astrocyte-regulated human brain-microvascular endothelial cells (HBMECs) and to restrain the proliferation of malignant U87MG cells. TX-grafted ETP-SLNs (TX-ETP-SLNs) significantly enhanced the BBB permeability coefficient for ETP and raised the fluorescent intensity of calcein-AM when compared with ETP-SLNs. In addition, surface MA could increase the BBB permeability coefficient for ETP about twofold. The viability of HBMECs was higher than 86%, suggesting a high biocompatibility of MA-TX-ETP-SLNs. Moreover, the efficiency in antiproliferation against U87MG cells was in the order of MA-TX-ETP-SLNs  >  TX-ETP-SLNs  >  ETP-SLNs  >  SLNs. The capability of MA-TX-ETP-SLNs to target HBMECs and U87MG cells during internalization was verified by immunochemical staining of expressed melanotransferrin. MA-TX-ETP-SLNs can be a potent pharmacotherapy to deliver ETP across the BBB to GBM. PMID:26768307

  19. The 3D fault and vein architecture of strike-slip releasing- and restraining bends: Evidence from volcanic-centre-relatedmineral deposits

    USGS Publications Warehouse

    Berger, B.R.

    2007-01-01

    High-temperature, volcanic-centre-related hydrothermal systems involve large fluid-flow volumes and are observed to have high discharge rates in the order of 100-400 kg/s. The flows and discharge occur predominantly on networks of critically stressed fractures. The coupling of hydrothermal fluid flow with deformation produces the volumes of veins found in epithermal mineral deposits. Owing to this coupling, veins provide information on the fault-fracture architecture in existence at the time of mineralization. They therefore provide information on the nature of deformation within fault zones, and the relations between different fault sets. The Virginia City and Goldfield mining districts, Nevada, were localized in zones of strike-slip transtension in an Early to Mid-Miocene volcanic belt along the western margin of North America. The Camp Douglas mining area occurs within the same belt, but is localized in a zone of strike-slip transpression. The vein systems in these districts record the spatial evolution of strike-slip extensional and contractional stepovers, as well as geometry of faulting in and adjacent to points along strike-slip faults where displacement has been interrupted and transferred into releasing and restraining stepovers. ?? The Geological Society of London 2007.

  20. Huaier restrains proliferative and invasive potential of human hepatoma SKHEP-1 cells partially through decreased Lamin B1 and elevated NOV

    PubMed Central

    Hu, Zhongdong; Yang, Ailin; Su, Guozhu; Zhao, Yunfang; Wang, Ying; Chai, Xingyun; Tu, Pengfei

    2016-01-01

    Hepatocellular carcinoma (HCC) is one of the most common cause of malignancy-related mortality worldwide. It is urgently needed to develop potential drugs with good efficacy and low toxicity for HCC treatment. The anti-tumor effect of Traditional Chinese Medicine (TCM) has received increasing attention worldwide. Trametes robiniophila Murr. (Huaier) has been used in TCM for approximately 1,600 years. Clinically, Huaier has satisfactory therapeutic effects in cancer treatment, especially in HCC. However, the mechanisms underlying the anti-cancer effect of Huaier remain ill defined. Herein we have demonstrated that Huaier dramatically inhibited cell proliferation and induced apoptosis in human hepatoma cell line SKHEP-1. Importantly, Huaier restrained the metastatic capability of SKHEP-1 cells. Mechanistically, down-regulation of Lamin B1 and up-regulation of Nephroblastoma overexpressed (NOV) were at least partially responsible for the inhibitory effect of Huaier on the proliferative and invasive capacity of SKHEP-1 cells. Our finding provided new insights into mechanisms of anti-HCC effect of Huaier and suggested a new scientific basis for clinical medication. PMID:27503760

  1. Simulated annealing with restrained molecular dynamics using CONGEN: energy refinement of the NMR solution structures of epidermal and type-alpha transforming growth factors.

    PubMed Central

    Tejero, R.; Bassolino-Klimas, D.; Bruccoleri, R. E.; Montelione, G. T.

    1996-01-01

    The new functionality of the program CONGEN (Bruccoleri RE, Karplus M, 1987, Biopolymers 26:137-168; Bassolino-Klimas D et al., 1996, Protein Sci 5:593-603) has been applied for energy refinement of two previously determined solution NMR structures, murine epidermal growth factor (mEGF) and human type-alpha transforming growth factor (hTGF alpha). A summary of considerations used in converting experimental NMR data into distance constraints for CONGEN is presented. A general protocol for simulated annealing with restrained molecular dynamics is applied to generate NMR solution structures using CONGEN together with real experimental NMR data. A total of 730 NMR-derived constraints for mEGF and 424 NMR-derived constraints for hTGF alpha were used in these energy-refinement calculations. Different weighting schemes and starting conformations were studied to check and/or improve the sampling of the low-energy conformational space that is consistent with all constraints. The results demonstrate that loosened (i.e., "relaxed") sets of the EGF and hTGF alpha internuclear distance constraints allow molecules to overcome local minima in the search for a global minimum with respect to both distance restraints and conformational energy. The resulting energy-refined structures of mEGF and hTGF alpha are compared with structures determined previously and with structures of homologous proteins determined by NMR and X-ray crystallography. PMID:8845748

  2. Importance of antimicrobial stewardship to the English National Health Service

    PubMed Central

    Dixon, Jill; Duncan, Christopher JA

    2014-01-01

    Antimicrobials are an extremely valuable resource across the spectrum of modern medicine. Their development has been associated with dramatic reductions in communicable disease mortality and has facilitated technological advances in cancer therapy, transplantation, and surgery. However, this resource is threatened by the dwindling supply of new antimicrobials and the global increase in antimicrobial resistance. There is an urgent need for antimicrobial stewardship (AMS) to protect our remaining antimicrobials for future generations. AMS emphasizes sensible, appropriate antimicrobial management for the benefit of the individual and society as a whole. Within the English National Health Service (NHS), a series of recent policy initiatives have focused on all aspects of AMS, including best practice guidelines for antimicrobial prescribing, enhanced surveillance mechanisms for monitoring antimicrobial use across primary and secondary care, and new prescribing competencies for doctors in training. Here we provide a concise summary to clarify the current position and importance of AMS within the NHS and review the evidence base for AMS recommendations. The evidence supports the impact of AMS strategies on modifying prescribing practice in hospitals, with beneficial effects on both antimicrobial resistance and the incidence of Clostridium difficile, and no evidence of increased sepsis-related mortality. There is also a promising role for novel diagnostic technologies in AMS, both in enhancing microbiological diagnosis and improving the specificity of sepsis diagnosis. More work is needed to establish an evidence base for interventions to improve public and patient education regarding the role of antibiotics in common clinical syndromes, such as respiratory tract infection. Future priorities include establishing novel approaches to antimicrobial management (eg, duration of therapy, combination regimens) to protect against resistance and working with the pharmaceutical

  3. Comparative surface antimicrobial properties of synthetic biocides and novel human apolipoprotein E derived antimicrobial peptides.

    PubMed

    Forbes, Sarah; McBain, Andrew J; Felton-Smith, Susan; Jowitt, Thomas A; Birchenough, Holly L; Dobson, Curtis B

    2013-07-01

    Medical device infection remains a major clinical concern. Biocidal compounds have been incorporated into medical device materials ideally to inhibit bacterial colonisation whilst exhibiting relatively low cytotoxicity. We compared the antibacterial activity, anti-biofilm efficacy and cytotoxicity of a novel peptide derivative of human apolipoprotein E (apoEdpL-W) to that of commonly used biocides, before and after coating onto a range of standard polymers. Since the antimicrobial function of most biocides frequently involves associations with cellular membranes, we have also studied the detailed interactions of the test antimicrobials with phospholipid bilayers, using the quartz crystal microbalance device combined with dual-polarisation interferometry. ApoEdpL-W displayed broad-spectrum antibacterial activity and marked efficacy against nascent Staphylococcus aureus biofilms. Compounds showed better antimicrobial activity when combined with hydrogel materials than with non-porous materials. The membrane interactions of apoEdpL-W were most similar to that of PHMB, with both agents appearing to readily bind and insert into lipid bilayers, possibly forming pores. However apoEdpL-W showed lower cytotoxicity than PHMB, its efficacy was less affected by the presence of serum, and it demonstrated the highest level of biocompatibility of all the biocides, as indicated by our measurement of its antimicrobial biocompatibility index. This work shows the potential of apoEdpL-W as an effective antiseptic coating agent. PMID:23623325

  4. Use and misuse of antimicrobial drugs in poultry and livestock: Mechanisms of antimicrobial resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Food safety begins on the farm with management practices that contribute to an abundant, safe, and affordable food supply. To attain this goal, antimicrobials have been used in all stages of food animal production in the United States and elsewhere around the world at one time or another. Among fo...

  5. Antimicrobial peptides: a review of how peptide structure impacts antimicrobial activity

    NASA Astrophysics Data System (ADS)

    Soares, Jason W.; Mello, Charlene M.

    2004-03-01

    Antimicrobial peptides (AMPs) have been discovered in insects, mammals, reptiles, and plants to protect against microbial infection. Many of these peptides have been isolated and studied exhaustively to decipher the molecular mechanisms that impart protection against infectious bacteria, fungi, and viruses. Unfortunately, the molecular mechanisms are still being debated within the scientific community but valuable clues have been obtained through structure/function relationship studies1. Biophysical studies have revealed that cecropins, isolated from insects and pigs, exhibit random structure in solution but undergo a conformational change to an amphipathic α-helix upon interaction with a membrane surface2. The lack of secondary structure in solution results in an extremely durable peptide able to survive exposure to high temperatures, organic solvents and incorporation into fibers and films without compromising antibacterial activity. Studies to better understand the antimicrobial action of cecropins and other AMPs have provided insight into the importance of peptide sequence and structure in antimicrobial activities. Therefore, enhancing our knowledge of how peptide structure imparts function may result in customized peptide sequences tailored for specific applications such as targeted cell delivery systems, novel antibiotics and food preservation additives. This review will summarize the current state of knowledge with respect to cell binding and antimicrobial activity of AMPs focusing primarily upon cecropins.

  6. ASSOCIATION OF ANTIMICROBIAL RESISTANCE PATTERNS AND REPORTED USAGE OF ANTIMICROBIALS IN COMMERCIAL GROWING PIGS PRODUCTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The relationship between microbial use and the development of resistance to antimicrobials has been demonstrated through both external models and has been observed clinically. However, the strength of this relationship in practical production systems has not been clearly quantified. We designed th...

  7. Antimicrobial susceptibility of Leptospira isolates from dogs and rats to 12 antimicrobial agents.

    PubMed

    Suepaul, S M; Carrington, C; Campbell, M; Borde, G; Adesiyun, A A

    2015-03-01

    This study determined the antimicrobial susceptibilities of 67 isolates of Leptospira from dogs (suspect canine cases: n=7 and stray dogs: n=6) and rodents (n=54) in Trinidad to 12 antimicrobial agents using broth microdilution and macrodilution techniques. Commonly used antimicrobial agents such as the penicillin G and ceftriaxone had relatively low minimal inhibitory concentrations (MICs) while doxycycline displayed a relatively higher value but was still considered to be effective. While imipenem was the most effective with low MIC values in vitro, sulphamethoxazole-trimethoprim had the highest i.e. least effective. Based on these results, the drugs commonly used in the treatment of leptospirosis (penicillin G, penicillin-streptomycin, doxycycline and ceftriaxone) in both humans and animals in Trinidad appear to have similar MICs and MBCs in vitro when compared with published reports. The serovar of Leptospira spp. and in most cases the origin of the isolates did not significantly (P>0.05) influence their susceptibilities to the antimicrobial agents tested. PMID:25801249

  8. In vitro susceptibility of Bordetella parapertussis to various antimicrobial agents.

    PubMed Central

    Watanabe, M; Haraguchi, Y

    1989-01-01

    The in vitro activity of 18 antimicrobial agents against 32 strains of Bordetella parapertussis isolated from whooping cough patients was studied. The most active antimicrobial agents were piperacillin and minocycline, followed (in descending order of activity) by moxalactam, erythromycin, cefoperazone, tetracycline, ampicillin, cefotaxime, chloramphenicol, josamycin, sulfamethoxazole, and nalidixic acid. Isolates were resistant to benzylpenicillin, cephalothin, cefatrizine, cefaclor, streptomycin, and cephalexin. PMID:2764546

  9. ANTIMICROBIAL RESISTANCE PATTERNS OF SALMONELLA FROM RETAIL CHICKEN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Salmonella is frequently reported as a cause of food-borne illness. The emergence of antimicrobial resistant Salmonella associated with meat products has heightened concerns regarding antimicrobial use in food animal production. Eighty Salmonella isolates recovered from fresh whole chicken carcass...

  10. Klebsiella pneumoniae Antimicrobial Drug Resistance, United States, 1998–2010

    PubMed Central

    Sanchez, Guillermo V.; Master, Ronald N.; Clark, Richard B.; Fyyaz, Madiha; Duvvuri, Padmaraj; Ekta, Gupta

    2013-01-01

    We studied antimicrobial-resistant Klebsiella pneumoniae for 1998–2010 by using data from The Surveillance Network. Susceptibility results (n = 3,132,354) demonstrated significant increases in resistance to all antimicrobial drugs studied, except tetracycline. Cross-resistance among carbapenem-resistant K. pneumoniae was lower for tetracycline and amikacin. PMID:23260464

  11. High-Throughput Intracellular Antimicrobial Susceptibility Testing of Legionella pneumophila

    PubMed Central

    Chiaraviglio, Lucius

    2015-01-01

    Legionella pneumophila is a Gram-negative opportunistic human pathogen that causes a severe pneumonia known as Legionnaires' disease. Notably, in the human host, the organism is believed to replicate solely within an intracellular compartment, predominantly within pulmonary macrophages. Consequently, successful therapy is predicated on antimicrobials penetrating into this intracellular growth niche. However, standard antimicrobial susceptibility testing methods test solely for extracellular growth inhibition. Here, we make use of a high-throughput assay to characterize intracellular growth inhibition activity of known antimicrobials. For select antimicrobials, high-resolution dose-response analysis was then performed to characterize and compare activity levels in both macrophage infection and axenic growth assays. Results support the superiority of several classes of nonpolar antimicrobials in abrogating intracellular growth. Importantly, our assay results show excellent correlations with prior clinical observations of antimicrobial efficacy. Furthermore, we also show the applicability of high-throughput automation to two- and three-dimensional synergy testing. High-resolution isocontour isobolograms provide in vitro support for specific combination antimicrobial therapy. Taken together, findings suggest that high-throughput screening technology may be successfully applied to identify and characterize antimicrobials that target bacterial pathogens that make use of an intracellular growth niche. PMID:26392509

  12. National Antimicrobial Resistance Monitoring System (NARMS) 2010 Report

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In an effort to prospectively monitor the emergence of antimicrobial resistance in zoonotic pathogens, the National Antimicrobial Resistance Monitoring System (NARMS) was established in 1996 by the Food and Drug Administration’s Center for Veterinary Medicine in collaboration with the Centers for Di...

  13. High-Throughput Intracellular Antimicrobial Susceptibility Testing of Legionella pneumophila.

    PubMed

    Chiaraviglio, Lucius; Kirby, James E

    2015-12-01

    Legionella pneumophila is a Gram-negative opportunistic human pathogen that causes a severe pneumonia known as Legionnaires' disease. Notably, in the human host, the organism is believed to replicate solely within an intracellular compartment, predominantly within pulmonary macrophages. Consequently, successful therapy is predicated on antimicrobials penetrating into this intracellular growth niche. However, standard antimicrobial susceptibility testing methods test solely for extracellular growth inhibition. Here, we make use of a high-throughput assay to characterize intracellular growth inhibition activity of known antimicrobials. For select antimicrobials, high-resolution dose-response analysis was then performed to characterize and compare activity levels in both macrophage infection and axenic growth assays. Results support the superiority of several classes of nonpolar antimicrobials in abrogating intracellular growth. Importantly, our assay results show excellent correlations with prior clinical observations of antimicrobial efficacy. Furthermore, we also show the applicability of high-throughput automation to two- and three-dimensional synergy testing. High-resolution isocontour isobolograms provide in vitro support for specific combination antimicrobial therapy. Taken together, findings suggest that high-throughput screening technology may be successfully applied to identify and characterize antimicrobials that target bacterial pathogens that make use of an intracellular growth niche. PMID:26392509

  14. Antimicrobial activity of chicken NK-lysin against Eimeria sporozoites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    NK-lysin is an antimicrobial and antitumor polypeptide that is considered to play an important role during innate immunity. Chicken NK-lysin is a member of the saposin-like protein family and exhibits potent antitumor cell activity. To evaluate the antimicrobial properties of chicken NK-lysin, we ex...

  15. Antimicrobial volatile essential oils in edible films for food safety

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This book chapter provides a comprehensive update of experimental use of antimicrobial volatile essential oils in edible film applications. It reviews the most recent advancement in edible film technology to promote food safety. A brief description of how these antimicrobial edible films are produ...

  16. Food Production and Antimicrobial Resistance – The Next 100 Years

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production of food is complex and ensuring the safety of food for human consumption provides serious challenges. Since 1996 the U.S. has conducted surveillance on food borne and commensal antimicrobial resistance bacteria through the National Antimicrobial Resistance Monitoring System - Enteric Bac...

  17. Shigella Antimicrobial Drug Resistance Mechanisms, 2004-2014.

    PubMed

    Nüesch-Inderbinen, Magdalena; Heini, Nicole; Zurfluh, Katrin; Althaus, Denise; Hächler, Herbert; Stephan, Roger

    2016-06-01

    To determine antimicrobial drug resistance mechanisms of Shigella spp., we analyzed 344 isolates collected in Switzerland during 2004-2014. Overall, 78.5% of isolates were multidrug resistant; 10.5% were ciprofloxacin resistant; and 2% harbored mph(A), a plasmid-mediated gene that confers reduced susceptibility to azithromycin, a last-resort antimicrobial agent for shigellosis. PMID:27191035

  18. P10 ALTERNATIVE USES AND COLLATERAL EFFECTS OF ANTIMICROBIALS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Throughout history and nature, antimicrobials have had applications in addition to treating diseases. Certain insects use antimicrobials as disinfectants. Ancient Nubians incorporated antibiotics in the manufacture of ‘booza’, a traditional alcoholic beverage in their culture. For the last four d...

  19. Antimicrobial activity of Caesalpinia pulcherrima, Euphorbia hirta and Asystasia gangeticum.

    PubMed

    Sudhakar, M; Rao, Ch V; Rao, P M; Raju, D B; Venkateswarlu, Y

    2006-07-01

    The ethanolic extracts of the dry fruits of Caesalpinia pulcherrima, aerial parts of Euphorbia hirta and flowers of Asystasia gangeticum were tested for antimicrobial activity. The three plants exhibited a broad spectrum of antimicrobial activity, particularly against Escherichia coli (enteropathogen), Proteus vulgaris, Pseudomonas aeruginosa and Staphylococcus aureus. PMID:16730921

  20. Shigella Antimicrobial Drug Resistance Mechanisms, 2004–2014

    PubMed Central

    Nüesch-Inderbinen, Magdalena; Heini, Nicole; Zurfluh, Katrin; Althaus, Denise; Hächler, Herbert

    2016-01-01

    To determine antimicrobial drug resistance mechanisms of Shigella spp., we analyzed 344 isolates collected in Switzerland during 2004–2014. Overall, 78.5% of isolates were multidrug resistant; 10.5% were ciprofloxacin resistant; and 2% harbored mph(A), a plasmid-mediated gene that confers reduced susceptibility to azithromycin, a last-resort antimicrobial agent for shigellosis. PMID:27191035