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Sample records for broad-spectrum antimicrobial chlorhexidine

  1. Potential Adverse Effects of Broad-Spectrum Antimicrobial Exposure in the Intensive Care Unit.

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    Wiens, Jenna; Snyder, Graham M; Finlayson, Samuel; Mahoney, Monica V; Celi, Leo Anthony

    2018-02-01

    The potential adverse effects of empiric broad-spectrum antimicrobial use among patients with suspected but subsequently excluded infection have not been fully characterized. We sought novel methods to quantify the risk of adverse effects of broad-spectrum antimicrobial exposure among patients admitted to an intensive care unit (ICU). Among all adult patients admitted to ICUs at a single institution, we selected patients with negative blood cultures who also received ≥1 broad-spectrum antimicrobials. Broad-spectrum antimicrobials were categorized in ≥1 of 5 categories based on their spectrum of activity against potential pathogens. We performed, in serial, 5 cohort studies to measure the effect of each broad-spectrum category on patient outcomes. Exposed patients were defined as those receiving a specific category of broad-spectrum antimicrobial; nonexposed were all other patients in the cohort. The primary outcome was 30-day mortality. Secondary outcomes included length of hospital and ICU stay and nosocomial acquisition of antimicrobial-resistant bacteria (ARB) or Clostridium difficile within 30 days of admission. Among the study cohort of 1918 patients, 316 (16.5%) died within 30 days, 821 (42.8%) had either a length of hospital stay >7 days or an ICU length of stay >3 days, and 106 (5.5%) acquired either a nosocomial ARB or C. difficile . The short-term use of broad-spectrum antimicrobials in any of the defined broad-spectrum categories was not significantly associated with either primary or secondary outcomes. The prompt and brief empiric use of defined categories of broad-spectrum antimicrobials could not be associated with additional patient harm.

  2. Impact of broad-spectrum antimicrobial treatment on the ecology of intestinal flora.

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    Yang, Jen-Jia; Wang, Jann-Tay; Cheng, Aristine; Chuang, Yu-Chung; Sheng, Wang-Huei

    2017-06-28

    Suppression of intestinal flora by broad-spectrum antimicrobial agents facilitated risk of colonization or infection with resistant pathogen. We aimed to investigate the changes in bowel carriage of target resistant microorganisms (TRO) among patients treated with three different classes of Pseudomonas-sparing broad-spectrum antimicrobial agents (ertapenem, moxifloxacin and flomoxef) with anaerobic coverage. Risk factors for developing colonization of TRO were also analyzed. We prospectively enrolled the adult hospitalized patients (>20 years old) who were indicated for at least 7-day course with either of ertapenem, moxifloxacin or flomoxef. Rectal swabs were performed for the patients who received at least 1-day course of study antibiotics during the treatment duration. The TROs included Pseudomonas aeruginosa, Enterobacteriaceae, and Acinetobacter baumannii. MacConkey agars with study antibiotics were used to isolate the TROs and evaluate the antimicrobial resistance. The mean age of our study population was 61.6 years, and 58.8% were males. The rates of rectal colonization for Pseudomonas aeruginosa was similar among the study medications (ertapenem 13.2%, flomoxef 20%, moxifloxacin 14.3%, p = 0.809). Compared with ertapenem, flomoxef (odds ratio [OR], 4.30; 95% confidence interval [95% CI], 1.28-14.48, p = 0.019) and moxifloxacin (OR, 6.95; 95% CI, 1.36-35.52, p = 0.019) had higher risk for colonization of ertapenem-resistant Escherichiacoli colonization. The patients who received treatment of ertapenem may have a lower risk of rectal colonization for ertapenem resistant Escherichia coli than those who received flomoxef or moxifloxacin. The rate of Pseudomonas colonization did not differ between the three study Pseudomonas-sparing agents. Copyright © 2017. Published by Elsevier B.V.

  3. Brevibacillus laterosporus, a Pathogen of Invertebrates and a Broad-Spectrum Antimicrobial Species

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    Luca Ruiu

    2013-09-01

    Full Text Available Brevibacillus laterosporus, a bacterium characterized by the production of a unique canoe-shaped lamellar body attached to one side of the spore, is a natural inhabitant of water, soil and insects. Its biopesticidal potential has been reported against insects in different orders including Coleoptera, Lepidoptera, Diptera and against nematodes and mollusks. In addition to its pathogenicity against invertebrates, different B. laterosporus strains show a broad-spectrum antimicrobial activity including activity against phytopathogenic bacteria and fungi. A wide variety of molecules, including proteins and antibiotics, have been associated with the observed pathogenicity and mode of action. Before being considered as a biological control agent against plant pathogens, the antifungal and antibacterial properties of certain B. laterosporus strains have found medical interest, associated with the production of antibiotics with therapeutic effects. The recent whole genome sequencing of this species revealed its potential to produce polyketides, nonribosomal peptides, and toxins. Another field of growing interest is the use of this bacterium for bioremediation of contaminated sites by exploiting its biodegradation properties. The aim of the present review is to gather and discuss all recent findings on this emerging entomopathogen, giving a wider picture of its complex and broad-spectrum biocontrol activity.

  4. Novel α-MSH peptide analogues with broad spectrum antimicrobial activity.

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    Paolo Grieco

    Full Text Available Previous investigations indicate that α-melanocyte-stimulating hormone (α-MSH and certain synthetic analogues of it exert antimicrobial effects against bacteria and yeasts. However, these molecules have weak activity in standard microbiology conditions and this hampers a realistic clinical use. The aim in the present study was to identify novel peptides with broad-spectrum antimicrobial activity in growth medium. To this purpose, the Gly10 residue in the [DNal(2'-7, Phe-12]-MSH(6-13 sequence was replaced with conventional and unconventional amino acids with different degrees of conformational rigidity. Two derivatives in which Gly10 was replaced by the residues Aic and Cha, respectively, had substantial activity against Candida strains, including C. albicans, C. glabrata, and C. krusei and against gram-positive and gram-negative bacteria. Conformational analysis indicated that the helical structure along residues 8-13 is a key factor in antimicrobial activity. Synthetic analogues of α-MSH can be valuable agents to treat infections in humans. The structural preferences associated with antimicrobial activity identified in this research can help further development of synthetic melanocortins with enhanced biological activity.

  5. Modified lysozymes as novel broad spectrum natural antimicrobial agents in foods.

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    Aminlari, Ladan; Hashemi, Marjan Mohammadi; Aminlari, Mahmoud

    2014-06-01

    In recent years much attention and interest have been directed toward application of natural antimicrobial agents in foods. Some naturally occurring proteins such as lactoperoxidase, lactoferrin, and lysozyme have received considerable attention and are being considered as potential antimicrobial agents in foods. Lysozyme kills bacteria by hydrolyzing the peptidoglycan layer of the cell wall of certain bacterial species, hence its application as a natural antimicrobial agent has been suggested. However, limitations in the action of lysozyme against only Gram-positive bacteria have prompted scientists to extend the antimicrobial effects of lysozyme by several types of chemical modifications. During the last 2 decades extensive research has been directed toward modification of lysozyme in order to improve its antimicrobial properties. This review will report on the latest information available on lysozyme modifications and examine the applicability of the modified lysozymes in controlling growth of Gram-positive and Gram-negative bacteria in foods. The results of modifications of lysozyme using its conjugation with different small molecule, polysaccharides, as well as modifications using proteolytic enzymes will be reviewed. These types of modifications have not only increased the functional properties of lysozyme (such as solubility and heat stability) but also extended the antimicrobial activity of lysozyme. Many examples will be given to show that modification can decrease the count of Gram-negative bacteria in bacterial culture and in foods by as much as 5 log CFU/mL and in some cases essentially eliminated Escherichia coli. In conclusion this review demonstrates that modified lysozymes are excellent natural food preservatives, which can be used in food industry. The subject described in this review article can lead to the development of methods to produce new broad-spectrum natural antimicrobial agents, based on modification of chicken egg white lysozyme, which

  6. Broad spectrum antimicrobial activity of melimine covalently bound to contact lenses.

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    Dutta, Debarun; Cole, Nerida; Kumar, Naresh; Willcox, Mark D P

    2013-01-07

    To develop a stable antimicrobial contact lens, which is effective against the International Organization for Standardization (ISO) panel microorganisms, Acanthamoeba castellanii and drug resistant strains of Pseudomonas aeruginosa and Staphylococcus aureus. Melimine was covalently incorporated into etafilcon A lenses. The amount of peptide present on the lens surface was quantified using amino acid analysis. After coating, the heat stability (121°C), lens surface hydrophobicity (by captive bubble), and in vitro cytotoxicity to mouse L929 cells of the lenses were investigated. Antimicrobial activity against the micro-organisms was evaluated by viable plate count and fluorescence microscopy, measuring the proportion of cell death compared with control lenses with no melimine. The most effective concentration was determined to be 152 ± 44 μg lens(-1) melimine on the lens surface. After coating, lenses were relatively hydrophilic and were nontoxic to mammalian cells. The activity remained high after autoclaving (e.g., 3.1, 3.9, 1.2, and 1.0 log inhibition against P. aeruginosa, S. aureus, A. castellanii, and Fusarium solani, respectively). Fluorescence microscopy confirmed significantly reduced (P bacteria to melimine contact lenses. Viable count confirmed that lenses were active against all the bacteria and fungi from the ISO panel, Acanthamoeba and gave at least 2 log inhibition against all the multidrug resistant S. aureus and P. aeruginosa strains. Melimine may offer excellent potential for development as a broad spectrum antimicrobial coating for contact lenses, showing activity against all the bacterial and fungal ISO panel microorganisms, Acanthamoeba, and antibiotic resistant strains of P. aeruginosa and S. aureus.

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

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    Anantharaman, Aparna; Sahal, Dinkar

    2010-08-26

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

  8. Novel engineered cationic antimicrobial peptides display broad-spectrum activity against Francisella tularensis, Yersinia pestis and Burkholderia pseudomallei.

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    Abdelbaqi, Suha; Deslouches, Berthony; Steckbeck, Jonathan; Montelaro, Ronald; Reed, Douglas S

    2016-02-01

    Broad-spectrum antimicrobials are needed to effectively treat patients infected in the event of a pandemic or intentional release of a pathogen prior to confirmation of the pathogen's identity. Engineered cationic antimicrobial peptides (eCAPs) display activity against a number of bacterial pathogens including multi-drug-resistant strains. Two lead eCAPs, WLBU2 and WR12, were compared with human cathelicidin (LL-37) against three highly pathogenic bacteria: Francisella tularensis, Yersinia pestis and Burkholderia pseudomallei. Both WLBU2 and WR12 demonstrated bactericidal activity greater than that of LL-37, particularly against F. tularensis and Y. pestis. Only WLBU2 had bactericidal activity against B. pseudomallei. WLBU2, WR12 and LL-37 were all able to inhibit the growth of the three bacteria in vitro. Because these bacteria can be facultative intracellular pathogens, preferentially infecting macrophages and dendritic cells, we evaluated the activity of WLBU2 against F. tularensis in an ex vivo infection model with J774 cells, a mouse macrophage cell line. In that model WLBU2 was able to achieve greater than 50% killing of F. tularensis at a concentration of 12.5 μM. These data show the therapeutic potential of eCAPs, particularly WLBU2, as a broad-spectrum antimicrobial for treating highly pathogenic bacterial infections.

  9. Novel Naja atra cardiotoxin 1 (CTX-1 derived antimicrobial peptides with broad spectrum activity.

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    Andrea Sala

    Full Text Available Naja atra subsp. atra cardiotoxin 1 (CTX-1, produced by Chinese cobra snakes, belonging to Elapidae family, is included in the three-finger toxin family and exerts high cytotoxicity and antimicrobial activity too. Using as template mainly the tip and the subsequent β-strand of the first "finger" of this toxin, different sequences of 20 amino acids linear peptides have been designed in order to avoid toxic effects but to maintain or even strengthen the partial antimicrobial activity already seen for the complete toxin. As a result, the sequence NCP-0 (Naja Cardiotoxin Peptide-0 was designed as ancestor and subsequently 4 other variant sequences of NCP-0 were developed. These synthesized variant sequences have shown microbicidal activity towards a panel of reference and field strains of Gram-positive and Gram-negative bacteria. The sequence named NCP-3, and its variants NCP-3a and NCP-3b, have shown the best antimicrobial activity, together with low cytotoxicity against eukaryotic cells and low hemolytic activity. Bactericidal activity has been demonstrated by minimum bactericidal concentration (MBC assay at values below 10 μg/ml for most of the tested bacterial strains. This potent antimicrobial activity was confirmed even for unicellular fungi Candida albicans, Candida glabrata and Malassezia pachydermatis (MBC 50-6.3 μg/ml, and against the fast-growing mycobacteria Mycobacterium smegmatis and Mycobacterium fortuitum. Moreover, NCP-3 has shown virucidal activity on Bovine Herpesvirus 1 (BoHV1 belonging to Herpesviridae family. The bactericidal activity is maintained even in a high salt concentration medium (125 and 250 mM NaCl and phosphate buffer with 20% Mueller Hinton (MH medium against E. coli, methicillin resistant Staphylococcus aureus (MRSA and Pseudomonas aeruginosa reference strains. Considering these in vitro obtained data, the search for active sequences within proteins presenting an intrinsic microbicidal activity could provide a

  10. Broad spectrum antimicrobial activity of forest-derived soil actinomycete, Nocardia sp. PB-52

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    Priyanka eSharma

    2016-03-01

    Full Text Available A mesophilic actinomycete strain designated as PB-52 was isolated from soil samples of Pobitora Wildlife Sanctuary of Assam, India. Based on phenotypic and molecular characteristics, the strain was identified as Nocardia sp. which shares 99.7% sequence similarity with Nocardia niigatensis IFM 0330 (NR_112195. The strain is a Gram-positive filamentous bacterium with rugose spore surface which exhibited a wide range of antimicrobial activity against Gram-positive bacteria including methicillin resistant Staphylococcus aureus (MRSA, Gram-negative bacteria and yeasts. Optimization for the growth and antimicrobial metabolite production of the strain PB-52 was carried out in batch culture under shaking condition. The optimum growth and the antimicrobial metabolite production by the strain PB-52 was recorded in GLM medium at 28ºC, initial pH 7.4 of the medium and incubation period of eight days. Based on polyketide synthases (PKS and nonribosomal peptide synthetases (NRPS gene-targeted PCR amplification, the occurrence of both of these biosynthetic pathways was detected which might be involved in the production of antimicrobial metabolite in PB-52. Extract of the fermented broth culture of PB-52 was prepared with organic solvent extraction method using ethyl acetate. The ethyl acetate extract of PB-52 (EA-PB-52 showed lowest minimum inhibitory concentration (MIC against Staphylococcus aureus MTCC 96 (0.975 μg/ml whereas highest was recorded against Klebsiella pneumoniae ATCC 13883 (62.5 μg/ml. Scanning electron microscopy (SEM revealed that treatment of the test microorganisms with EA-PB-52 destroyed the targeted cells with prominent loss of cell shape and integrity. In order to determine the constituents responsible for its antimicrobial activity, EA-PB-52 was subjected to chemical analysis using gas chromatography-mass spectrometry (GC-MS. GC-MS analysis showed the presence of twelve different chemical constituents in the extract, some of which

  11. Complete Genome Sequence of Bacillus velezensis YJ11-1-4, a Strain with Broad-Spectrum Antimicrobial Activity, Isolated from Traditional Korean Fermented Soybean Paste.

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    Lee, Hyo Jung; Chun, Byung-Hee; Jeon, Hye Hee; Kim, Yeon Bee; Lee, Se Hee

    2017-11-30

    Bacillus velezensis YJ11-1-4 is a strain that exhibits broad-spectrum antimicrobial activity against various pathogens. It was isolated from doenjang, a traditional Korean fermented soybean paste. The genome comprises a single circular chromosome of 4,006,637 bp with 46.42% G+C content without plasmids. Copyright © 2017 Lee et al.

  12. Endophytic Paraconiothyrium sp. from Zingiber officinale Rosc. Displays Broad-Spectrum Antimicrobial Activity by Production of Danthron.

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    Anisha, C; Sachidanandan, P; Radhakrishnan, E K

    2018-03-01

    The bioactivity spectrum of fungal endophytes isolated from Zingiber officinale was analyzed against clinical pathogens and against the phytopathogen Pythium myriotylum, which causes Pythium rot in ginger. One of the isolates GFM13 showed broad bioactivity against various pathogens tested including P. myriotylum. The spore suspension as well as the culture filtrate of the endophytic fungal isolate was found to effectively protect ginger rhizomes from Pythium rot. By molecular identification, the fungal endophyte was identified as Paraconiothyrium sp. The bioactive compound produced by the isolate was separated by bioactivity-guided fractionation and was identified by GC-MS as danthron, an anthraquinone derivative. PCR amplification showed the presence of non-reducing polyketide synthase gene (NR-PKS) in the endophyte GFM13, which is reported to be responsible for the synthesis of anthraquinones in fungi. This is the first report of danthron being produced as the biologically active component of Paraconiothyrium sp. Danthron is reported to have wide pharmaceutical and agronomic applications which include its use as a fungicide in agriculture. The broad-spectrum antimicrobial activity of danthron and the endophytic origin of Paraconiothyrium sp. offer immense applications of the study.

  13. Antimicrobial resistance in the Bacteroides fragilis group in faecal samples from patients receiving broad-spectrum antibiotics

    DEFF Research Database (Denmark)

    Møller Hansen, Kia Cirkeline; Ferløv-Schwensen, Simon Andreas; Henriksen, Daniel Pilsgaard

    2017-01-01

    Members of the Bacteroides fragilis group are opportunistic pathogens and cause severe infections including bacteraemia. As increased levels of antimicrobial resistance in B. fragilis group bacteria can be detected years after administration of specific antibiotics, monitoring antimicrobial...... susceptibility in the gut microbiota could be important. The objectives of this study were to 1) investigate the distribution of species and the occurrence of reduced antimicrobial susceptibility in the B. fragilis group from patients treated at departments with a high level of antibiotic use, 2) to determine...... the prevalence of the carbapenem resistance gene cfiA in B. fragilis in this patient group, and 3) to determine the association between previous antibiotic treatment and reduced susceptibility to clindamycin, meropenem, metronidazole, and piperacillin-tazobactam. Consecutive faecal samples (n = 197) were...

  14. The Freshwater Sponge Ephydatia fluviatilis Harbours Diverse Pseudomonas Species (Gammaproteobacteria, Pseudomonadales) with Broad-Spectrum Antimicrobial Activity

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    Keller-Costa, Tina; Jousset, Alexandre; van Overbeek, Leo; van Elsas, Jan Dirk; Costa, Rodrigo

    2014-01-01

    Bacteria are believed to play an important role in the fitness and biochemistry of sponges (Porifera). Pseudomonas species (Gammaproteobacteria, Pseudomonadales) are capable of colonizing a broad range of eukaryotic hosts, but knowledge of their diversity and function in freshwater invertebrates is rudimentary. We assessed the diversity, structure and antimicrobial activities of Pseudomonas spp. in the freshwater sponge Ephydatia fluviatilis. Polymerase Chain Reaction – Denaturing Gradient Gel Electrophoresis (PCR-DGGE) fingerprints of the global regulator gene gacA revealed distinct structures between sponge-associated and free-living Pseudomonas communities, unveiling previously unsuspected diversity of these assemblages in freshwater. Community structures varied across E. fluviatilis specimens, yet specific gacA phylotypes could be detected by PCR-DGGE in almost all sponge individuals sampled over two consecutive years. By means of whole-genome fingerprinting, 39 distinct genotypes were found within 90 fluorescent Pseudomonas isolates retrieved from E. fluviatilis. High frequency of in vitro antibacterial (49%), antiprotozoan (35%) and anti-oomycetal (32%) activities was found among these isolates, contrasting less-pronounced basidiomycetal (17%) and ascomycetal (8%) antagonism. Culture extracts of highly predation-resistant isolates rapidly caused complete immobility or lysis of cells of the protozoan Colpoda steinii. Isolates tentatively identified as P. jessenii, P. protegens and P. oryzihabitans showed conspicuous inhibitory traits and correspondence with dominant sponge-associated phylotypes registered by cultivation-independent analysis. Our findings suggest that E. fluviatilis hosts both transient and persistent Pseudomonas symbionts displaying antimicrobial activities of potential ecological and biotechnological value. PMID:24533086

  15. Comparative Evaluation of the Antimicrobial Properties of Glass Ionomer Cements with and without Chlorhexidine Gluconate.

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    Yadiki, Josna Vinutha; Jampanapalli, Sharada Reddy; Konda, Suhasini; Inguva, Hema Chandrika; Chimata, Vamsi Krishna

    2016-01-01

    Chlorhexidine gluconate is a widely used antimicrobial agent. Adding chlorhexidine and quaternary ammonium compounds to filling materials, such as composite resins, acrylic resins, and glass ionomer cements increases the antibacterial property of restorative materials. This study includes antibacterial property of glass ionomer restorative cements with chlorhexidine gluconate. The primary objective of our study was to compare the antimicrobial properties of two commercially available glass ionomer cements with and without chlorhexidine gluconate on strains of mutans streptococci. Two glass ionomers (Fuji II Conventional and Fuji IX) were used. Chlorhexidine gluconate was mixed with glass ionomer cements, and antimicrobial properties against mutans streptococci were assessed by agar diffusion. The tested bacterial strain was inhibited and the antimicrobial properties decreased with time. The highest amount of antimicrobial activity with mean inhibitory zone was found in Fuji II with chlorhexidine gluconate followed by Fuji IX with chlorhexidine gluconate, Fuji II without chlorhexidine gluconate, and Fuji IX without chlorhexidine gluconate. The results of the study confirmed that the addition of 5% chlorhexidine gluconate to Fuji II and Fuji IX glass ionomer cements resulted in a restorative material that had increased antimicrobial properties over the conventional glass ionomer cements alone for Streptococcus mutans. How to cite this article: Yadiki JV, Jampanapalli SR , Konda S, Inguva HC, Chimata VK. Comparative Evaluation of the Antimicrobial Properties of Glass Ionomer Cements with and without Chlorhexidine Gluconate. Int J Clin Pediatr Dent 2016;9(2):99-103.

  16. Broad spectrum bioactive sunscreens.

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    Velasco, Maria Valéria Robles; Sarruf, Fernanda Daud; Salgado-Santos, Idalina Maria Nunes; Haroutiounian-Filho, Carlos Alberto; Kaneko, Telma Mary; Baby, André Rolim

    2008-11-03

    The development of sunscreens containing reduced concentration of chemical UV filters, even though, possessing broad spectrum effectiveness with the use of natural raw materials that improve and infer UV absorption is of great interest. Due to the structural similarities between polyphenolic compounds and organic UV filters, they might exert photoprotection activity. The objective of the present research work was to develop bioactive sunscreen delivery systems containing rutin, Passiflora incarnata L. and Plantago lanceolata extracts associated or not with organic and inorganic UV filters. UV transmission of the sunscreen delivery system films was performed by using diffuse transmittance measurements coupling to an integrating sphere. In vitro photoprotection efficacy was evaluated according to the following parameters: estimated sun protection factor (SPF); Boot's Star Rating category; UVA/UVB ratio; and critical wavelength (lambda(c)). Sunscreen delivery systems obtained SPF values ranging from 0.972+/-0.004 to 28.064+/-2.429 and bioactive compounds interacted with the UV filters positive and negatively. This behavior may be attributed to: the composition of the delivery system; the presence of inorganic UV filter and quantitative composition of the organic UV filters; and the phytochemical composition of the P. incarnata L. and P. lanceolata extracts. Among all associations of bioactive compounds and UV filters, we found that the broad spectrum sunscreen was accomplished when 1.68% (w/w) P. incarnata L. dry extract was in the presence of 7.0% (w/w) ethylhexyl methoxycinnamate, 2.0% (w/w) benzophenone-3 and 2.0% (w/w) TiO(2). It was demonstrated that this association generated estimated SPF of 20.072+/-0.906 and it has improved the protective defense against UVA radiation accompanying augmentation of the UVA/UVB ratio from 0.49 to 0.52 and lambda(c) from 364 to 368.6nm.

  17. Evaluation of Novel Antimicrobial Peptides as Topical Anti-Infectives with Broad-Spectrum Activity against Combat-Related Bacterial and Fungal Wound Infections

    Science.gov (United States)

    2017-10-01

    that the dHDPs kill by disrupting membrane function . This is consistent with the amphipathic properties of the dHDPs and is a mechanism to which...recalcitrant biofilm are major obstacles in treating wounds. Antimicrobial peptides ( AMPs ), also known as host defense peptides, are evolutionarily highly...Designed antimicrobial peptides (dAMPs) are synthesized peptides that have been rationally designed based on sequences found in naturally occurring AMPs

  18. Antimicrobial peptides effectively kill a broad spectrum of Listeria monocytogenes and Staphylococcus aureus strains independently of origin, sub-type, or virulence factor expression

    DEFF Research Database (Denmark)

    Gottlieb, Caroline Trebbien; Thomsen, L.E.; Ingmer, H.

    2008-01-01

    -type, and phenotypic behavior. Strains within each species were equally sensitive to HDPs and oxidative stress representing important components of the innate immune defense system. Four non-human peptides (protamine, plectasin, novicidin, and novispirin G10) were similar in activity profile (MIC value spectrum......Background Host defense peptides (HDPs), or antimicrobial peptides (AMPs), are important components of the innate immune system that bacterial pathogens must overcome to establish an infection and HDPs have been suggested as novel antimicrobial therapeutics in treatment of infectious diseases...... Caenorhabditis elegans. For L. monocytogenes, proliferation in whole blood was paralleled by high invasion in Caco-2 cells and fast killing of C. elegans, however, no such pattern in phenotypic behavior was observed for S. aureus and none of the phenotypic differences were correlated to sensitivity to HDPs...

  19. Evaluation of Novel Antimicrobial Peptides as Topical Anti-Infectives with Broad Spectrum Activity Against Combat-Related Bacterial and Fungal Wound Infections

    Science.gov (United States)

    2016-10-01

    Inc. Vallejo, CA 94592 REPORT DATE: October 2016 TYPE OF REPORT: Annual PREPARED FOR: U.S. Army Medical Research and Materiel Command Fort...2016 2. REPORT TYPE Annual 3. DATES COVERED 30 Sep 2015 - 29 Sep 2016 4. TITLE AND SUBTITLE Evaluation of Novel Antimicrobial Peptides as Topical...antibiotics and early debridement has been associated with a large reduction in burn wound infections. Current topical antibiotics include

  20. Evaluation of Carbohydrate-Derived Fulvic Acid (CHD-FA) as a Topical Broad-Spectrum Antimicrobial for Drug-Resistant Wound Infections

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    2015-10-01

    Tests for Bacteria That Grow Aerobically ; Approved Standard – Eighth Edition” was used to determine the CHD-FA MIC values at a pH range of 3.0 to...preventing absorption of active compound (See Figure 13.) Also the topical cream formulation has been approved for 24 vaginitis to help control...Institute (CLSI) protocol M07-A9 “Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically ; Approved Standard

  1. Antimicrobial peptides effectively kill a broad spectrum of Listeria monocytogenes and Staphylococcus aureus strains independently of origin, sub-type, or virulence factor expression

    Directory of Open Access Journals (Sweden)

    Kristensen Hans-Henrik

    2008-11-01

    Full Text Available Abstract Background Host defense peptides (HDPs, or antimicrobial peptides (AMPs, are important components of the innate immune system that bacterial pathogens must overcome to establish an infection and HDPs have been suggested as novel antimicrobial therapeutics in treatment of infectious diseases. Hence it is important to determine the natural variation in susceptibility to HDPs to ensure a successful use in clinical treatment regimes. Results Strains of two human bacterial pathogens, Listeria monocytogenes and Staphylococcus aureus, were selected to cover a wide range of origin, sub-type, and phenotypic behavior. Strains within each species were equally sensitive to HDPs and oxidative stress representing important components of the innate immune defense system. Four non-human peptides (protamine, plectasin, novicidin, and novispirin G10 were similar in activity profile (MIC value spectrum to the human β-defensin 3 (HBD-3. All strains were inhibited by concentrations of hydrogen peroxide between 0.1% – 1.0%. Sub-selections of both species differed in expression of several virulence-related factors and in their ability to survive in human whole blood and kill the nematode virulence model Caenorhabditis elegans. For L. monocytogenes, proliferation in whole blood was paralleled by high invasion in Caco-2 cells and fast killing of C. elegans, however, no such pattern in phenotypic behavior was observed for S. aureus and none of the phenotypic differences were correlated to sensitivity to HDPs. Conclusion Strains of L. monocytogenes and S. aureus were within each species equally sensitive to a range of HDPs despite variations in subtype, origin, and phenotypic behavior. Our results suggest that therapeutic use of HDPs will not be hampered by occurrence of naturally tolerant strains of the two species investigated in the present study.

  2. Antimicrobial 2-hydroxyisocaproic acid and chlorhexidine resist inactivation by dentine.

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    Sakko, M; Tjäderhane, L; Sorsa, T; Hietala, P; Rautemaa, R

    2016-04-01

    To compare the antibacterial activity of 2-hydroxyisocaproic acid (HICA) with currently used root canal medicaments and to examine their interactions with potential inhibitors in nutrient-deficient and nutrient-rich conditions. First, the antibacterial activity of single concentrations of HICA, calcium hydroxide solution or slurry, chlorhexidine digluconate or acetate was tested against Enterococcus faecalis with and without potential inhibitors: dentine powder (DP), hydroxyapatite or bovine serum albumin, in a low concentration of peptone water. Relative viable counts were determined by culture at 1, 24 and 48 h. In the second set of experiments, the activity of three concentrations of HICA was evaluated against two isolates of E. faecalis with and without potential inhibitors in nutrient-rich thioglycollate broth using a modification of a standard microdilution method. The minimum bactericidal concentration was determined by culture at 1, 24 and 48 h. Concentrations of ≥33 mg mL(-1) of HICA were found to be bactericidal against E. faecalis in both nutrient-deficient and nutrient-rich environments at 24- to 48-h incubation, whereas the initial activity of Ca(OH)2 slurry was lost at 48-h incubation. HICA tolerated well all tested potential inhibitors up to 19 mg mL(-1) . DP concentrations higher than this inhibited its activity in a dose-dependent manner in both environments. DP demonstrated moderate antibacterial activity, and it enhanced the otherwise limited activity of Ca(OH)2 slurry and solution. DP did not impact on the activity of chlorhexidine. These results support the long-term antibacterial activity of HICA and indicate its tolerance to clinically relevant concentrations of dentine and other inhibitors commonly present in the root canal system. Therefore, HICA may have potential as an interappointment medication in the treatment of root canal infections. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  3. Evaluation of the antimicrobial activities of chlorhexidine gluconate, sodium hypochlorite and octenidine hydrochloride in vitro.

    Science.gov (United States)

    Tirali, Resmiye E; Bodur, Haluk; Sipahi, Bilge; Sungurtekin, Elif

    2013-04-01

    The objective of this study was to compare the antimicrobial activity of sodium hypochlorite (NaOCl), chlorhexidine gluconate (CHX) and octenidine hydrochloride (OCT) in different concentrations against endodontic pathogens in vitro. Agar diffusion procedure was used to determine the antimicrobial activity of the tested materials. Enterococcus faecalis, Candida albicans and the mixture of these were used for this study. In the agar diffusion test, 5.25% NaOCl exhibited better antimicrobial effect than the other concentrations of NaOCl for all strains. All concentrations of OCT were effective against C. albicans and E. faecalis. Some 0.2% CHX was ineffective on all microorganisms. Antibacterial effectiveness of all experimental solutions decreased on the mixture of all strains. Decreasing concentrations of NaOCl resulted in significantly reduced antimicrobial effect. © 2010 The Authors. Australian Endodontic Journal © 2010 Australian Society of Endodontology.

  4. Ciprofloxacin prophylaxis delays initiation of broad-spectrum antibiotic therapy and reduces the overall use of antimicrobial agents during induction therapy for acute leukaemia: A single-centre study.

    Science.gov (United States)

    Hallböök, Helene; Lidström, Anna-Karin; Pauksens, Karlis

    2016-01-01

    Due to an outbreak of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae, the routine use of fluoroquinolone prophylaxis was questioned. As a result, this study was conducted with the aim to evaluate the impact of ciprofloxacin-prophylaxis on the use of broad-spectrum antibioctics and anti-mycotics. A cohort of 139 consecutive patients with acute leukaemia treated with remission-inducing induction chemotherapy between 2004-2012 at the Department of Haematology in Uppsala University Hospital was analysed. Fifty-three patients (38%) received broad-spectrum antibiotics at the initiation of chemotherapy and were not eligible for prophylaxis. Of the remaining patients, the initiation of broad-spectrum antibiotics was delayed by 3 days in those receiving ciprofloxacin prophylaxis (n = 47) compared with those receiving no prophylaxis (n = 39). The median duration of systemic antibiotic treatment was 6 days shorter in patients receiving ciprofloxacin prophylaxis (12 vs 18 days; p = 0.0005) and the cumulative (total) median days on systemic antibiotic treatment was shortened by 8 days (15 vs 23 days, p = 0.0008). Piperacillin/tazobactam (p = 0.02), carbapenems (p = 0.05) and empiric broad-spectrum antifungals (p antibiotic use in this study. These benefits must be evaluated vs the risks of development of resistant bacterial strains, making fluoroquinolone prophylaxis an open question for debate.

  5. Antimicrobial activity of polyhexamethylene guanidine phosphate in comparison to chlorhexidine using the quantitative suspension method.

    Science.gov (United States)

    Vitt, A; Sofrata, A; Slizen, V; Sugars, R V; Gustafsson, A; Gudkova, E I; Kazeko, L A; Ramberg, P; Buhlin, K

    2015-07-17

    Polyhexamethylene guanidine phosphate (PHMG-P) belongs to the polymeric guanidine family of biocides and contains a phosphate group, which may confer better solubility, a detoxifying effect and may change the kinetics and dynamics of PHMG-P interactions with microorganisms. Limited data regarding PHMG-P activity against periodontopathogenic and cariogenic microorganisms necessitates studies in this area. Aim is to evaluate polyhexamethylene guanidine phosphate antimicrobial activity in comparison to chlorhexidine. Quantitative suspension method was used enrolling Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Streptococcus mutans and Lactobacillus acidophilus. Both tested antiseptics at their clinically-used concentrations, of 0.2% (w/v) and 1% (w/v), correspondingly provided swift bactericidal effects against S. aureus, P. aeruginosa, E. coli and C. albicans, A. actinomycetemcomitans and P. gingivalis with reduction factors higher than 6.0. Diluted polyhexamethylene guanidine phosphate and chlorhexidine to 0.05% continued to display anti-bacterial activity and decreased titers of standard quality control, periopathogens to below 1.0 × 10(3) colony forming units/ml, albeit requiring prolonged exposure time. To achieve a bactericidal effect against S. mutans, both antiseptics at all concentrations required a longer exposure time. We found that a clinically-used 1% of polyhexamethylene guanidine phosphate concentration did not have activity against L. acidophilus. High RF of polyhexamethylene guanidine phosphate and retention of bactericidal effects, even at 0.05%, support the use of polyhexamethylene guanidine phosphate as a biocide with sufficient anti-microbial activity against periopathogens. Polyhexamethylene guanidine phosphate displayed bactericidal activity against periopathogens and S. mutans and could potentially be applied in the management of oral

  6. Comparison of antimicrobial efficacy of chlorhexidine and combination mouth rinse in reducing the Mutans streptococcus count in plaque

    OpenAIRE

    Laxmi S Lakade; Preetam Shah; Dayanand Shirol

    2014-01-01

    Background: The removal of plaque is utmost important to control dental caries. But in children, factors like lack of dexterity, individual motivation and monitoring limit the effectiveness of tooth brushing. This necessitates the use of chemotherapeutic agents for control of plaque. Aims: To compare the antimicrobial efficacy of 0.2% chlorhexidine mouth rinse and mouth rinse containing 0.03% triclosan, 0.05% sodium fluoride, and 5% xylitol in reducing the Mutans streptococcus count in plaque...

  7. Antimicrobial effect of chlorhexidine on Aggregatibacter actinomycetemcomitans biofilms associated with peri-implantitis

    Directory of Open Access Journals (Sweden)

    Zeinab Kadkhoda

    2016-08-01

    Full Text Available Background. This study aimed to assessthe antimicrobial effect of chlorhexidine (CHX on Aggregatibacter actinomyce-temcomitans biofilms isolated from subgingival plaque of peri-implantitis lesions. Methods. Thirteen patients requiring peri-implantitis treatment were consecutively selected and their subgingival biofilm was collected by inserting fine sterile paper points into peri-implant pockets for 15 seconds. A. actinomycetemcomitans was isolated from the subgingival biofilm and cultured. In this study, the standard strain of A. actinomycetemcomitans served as the positive control group and a blank disc impregnated with water served as the negative control; 0.1 mL of the bacterial suspension was cultured on specific culture medium and blank discs (6 mm in diameter impregnated with 0.2%CHX mouthrinse (Behsa Pharmaceutical Co. and negative control discs were placed on two sides of the bacterial culture plate. The size of growth inhibition zone was measured by a blinded independent observer in millimetres. Results. According to the results of disc diffusion test, the mean diameter of growth inhibition zone of A. actinomycetem-comitans around discs impregnated with CHX was larger in both standard (positive control and biofilm samples of A. acti-nomycetemcomitans compared to the negative control group (blank disc (P<0.001. Conclusion. Use of0.2% CHX mouthwash had antibacterial effects on A. actinomycetemcomitans species isolated from peri-implantitis sites.

  8. Comparison of antimicrobial efficacy of chlorhexidine and combination mouth rinse in reducing the Mutans streptococcus count in plaque

    Directory of Open Access Journals (Sweden)

    Laxmi S Lakade

    2014-01-01

    Full Text Available Background: The removal of plaque is utmost important to control dental caries. But in children, factors like lack of dexterity, individual motivation and monitoring limit the effectiveness of tooth brushing. This necessitates the use of chemotherapeutic agents for control of plaque. Aims: To compare the antimicrobial efficacy of 0.2% chlorhexidine mouth rinse and mouth rinse containing 0.03% triclosan, 0.05% sodium fluoride, and 5% xylitol in reducing the Mutans streptococcus count in plaque. Materials and Methods: Thirty healthy children aged 8-10 years with dmft (decay component of three or four were selected. They were divided randomly into two groups: The control or chlorhexidine group and the study group or combination mouth rinse. Both the groups practiced rinsing with respective mouth wash for 1 min for 15 d twice a day. The plaque samples were collected and after incubation Mutans streptococcus count was estimated on the strips from the Dentocult SM kit and evaluated using manufacture′s chart. Statistical Analysis Used: Wilcoxon matched pairs signed ranks test and Mann-Whitney U test were used to analyze the findings. Results: Statistically significant reduction in the Mutans streptococci count in the plaque was seen in the control and study group from baseline level. But when both the groups were compared, the antimicrobial effect of chlorhexidine was more.

  9. Antimicrobial activity of ozone and NaF-chlorhexidine on early childhood caries

    Directory of Open Access Journals (Sweden)

    Marcos XIMENES

    Full Text Available Abstract An early childhood carie (ECC is an extremely destructive form of tooth decay. The aim of this study was to investigate the action of ozone (O3, and the association of sodium fluoride (NaF with chlorhexidine (CHX on bacteria related to ECC. Overnight culture of the bacteria was performed. On exponential phase the suspension was adjusted (101-108 CFU/mL. A drop (10μL of each concentration of bacteria was applied on sheep blood agar plates and treated with O3 (2, 20, 200, and 2,000 ppm; after 18 hours, recovery analysis of CFU verified the reduction of bacterial activity. For NaF-CHX, sterile 96-well plates were prepared and divided into groups: G1 (150 µL TSB; G2 (20 µL of bacteria + 25 µL CHX + 25 µL NaF; and G3 (150 µL TSB + 20 µL of bacteria + 50 µL water. The plates were verified by analysis of the optical density (0, 12, 14, 16, and 18 hours. The data from O3 test were submitted to ANOVA and Tukey’s test (p 3log10 (99.9% for all bacteria (ozone ≥ 20ppm, while the combination of NaF-CHX was more effective (p < 0.001 compared to each substance tested alone and the control group. The antimicrobial agents tested were able to inhibit all bacteria tested; O3 seemed to be a good alternative for controlling progression of carious lesions, while the association of NaF-CHX showed to be a good antimicrobial with easy and inexpensive application.

  10. Ru(CO)3Cl(Glycinate) (CORM-3): A Carbon Monoxide–Releasing Molecule with Broad-Spectrum Antimicrobial and Photosensitive Activities Against Respiration and Cation Transport in Escherichia coli

    OpenAIRE

    Wilson, Jayne Louise; Jesse, Helen E.; Hughes, Bethan; Lund, Victoria; Naylor, Kathryn; Davidge, Kelly S.; Cook, Gregory M.; Mann, Brian E.; Poole, Robert K.

    2013-01-01

    Aims: Carbon monoxide (CO) delivered to cells and tissues by CO-releasing molecules (CO-RMs) has beneficial\\ud and toxic effects not mimicked by CO gas. The metal carbonyl Ru(CO)3Cl(glycinate) (CORM-3) is a novel, potent\\ud antimicrobial agent. Here, we established its mode of action. Results: CORM-3 inhibits respiration in several\\ud bacterial and yeast pathogens. In anoxic Escherichia coli suspensions, CORM-3 first stimulates, then inhibits\\ud respiration, but much higher concentrations of ...

  11. Novel water-based antiseptic lotion demonstrates rapid, broad-spectrum kill compared with alcohol antiseptic.

    Science.gov (United States)

    Czerwinski, Steven E; Cozean, Jesse; Cozean, Colette

    2014-01-01

    A novel alcohol-based antiseptic and a novel water-based antiseptic lotion, both with a synergistic combination of antimicrobial ingredients containing 0.2% benzethonium chloride, were evaluated using the standard time-kill method against 25 FDA-specified challenge microorganisms. The purpose of the testing was to determine whether a non-alcohol product could have equivalent rapid and broad-spectrum kill to a traditional alcohol sanitizer. Both the alcohol- and water-based products showed rapid and broad-spectrum antimicrobial activity. The average 15-s kill was 99.999% of the challenge organism for the alcohol-based antiseptic and 99.971% for the water-based antiseptic. The alcohol-based product demonstrated 100% of peak efficacy (60s) within the first 15s, whereas the water-based product showed 99.97%. The novel alcohol-based antiseptic reduced concentrations of 100% of organisms by 99.999%, whereas the water-based antiseptic lotion showed the same reduction for 96% of organisms. A novel water-based antiseptic product demonstrated equivalent rapid, broad-spectrum antimicrobial activity to an alcohol-based sanitizer and provided additional benefits of reduced irritation, persistent effect, and greater efficacy against common viruses. The combination of rapid, broad-spectrum immediate kill and persistent efficacy against pathogens may have significant clinical benefit in limiting the spread of disease. Copyright © 2014 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

  12. Ru(CO)3Cl(Glycinate) (CORM-3): A Carbon Monoxide–Releasing Molecule with Broad-Spectrum Antimicrobial and Photosensitive Activities Against Respiration and Cation Transport in Escherichia coli

    Science.gov (United States)

    Wilson, Jayne Louise; Jesse, Helen E.; Hughes, Bethan; Lund, Victoria; Naylor, Kathryn; Davidge, Kelly S.; Cook, Gregory M.; Mann, Brian E.

    2013-01-01

    Abstract Aims: Carbon monoxide (CO) delivered to cells and tissues by CO-releasing molecules (CO-RMs) has beneficial and toxic effects not mimicked by CO gas. The metal carbonyl Ru(CO)3Cl(glycinate) (CORM-3) is a novel, potent antimicrobial agent. Here, we established its mode of action. Results: CORM-3 inhibits respiration in several bacterial and yeast pathogens. In anoxic Escherichia coli suspensions, CORM-3 first stimulates, then inhibits respiration, but much higher concentrations of CORM-3 than of a classic protonophore are required for stimulation. Proton translocation measurements (H+/O quotients, i.e., H+ extrusion on pulsing anaerobic cells with O2) show that respiratory stimulation cannot be attributed to true “uncoupling,” that is, dissipation of the protonmotive force, or to direct stimulation of oxidase activity. Our data are consistent with CORM-3 facilitating the electrogenic transmembrane movement of K+ (or Na+), causing a stimulation of respiration and H+ pumping to compensate for the transient drop in membrane potential (ΔΨ). The effects on respiration are not mimicked by CO gas or control Ru compounds that do not release CO. Inhibition of respiration and loss of bacterial viability elicited by CORM-3 are reversible by white light, unambiguously identifying heme-containing oxidase(s) as target(s). Innovation: This is the most complete study to date of the antimicrobial action of a CO-RM. Noteworthy are the demonstration of respiratory stimulation, electrogenic ion transport, and photosensitive activity, establishing terminal oxidases and ion transport as primary targets. Conclusion: CORM-3 has multifaceted effects: increased membrane permeability, inhibition of terminal oxidases, and perhaps other unidentified mechanisms underlie its effectiveness in tackling microbial pathogenesis. Antioxid. Redox Signal. 19, 497–509. PMID:23186316

  13. Ru(CO)3Cl(Glycinate) (CORM-3): a carbon monoxide-releasing molecule with broad-spectrum antimicrobial and photosensitive activities against respiration and cation transport in Escherichia coli.

    Science.gov (United States)

    Wilson, Jayne Louise; Jesse, Helen E; Hughes, Bethan; Lund, Victoria; Naylor, Kathryn; Davidge, Kelly S; Cook, Gregory M; Mann, Brian E; Poole, Robert K

    2013-08-10

    Carbon monoxide (CO) delivered to cells and tissues by CO-releasing molecules (CO-RMs) has beneficial and toxic effects not mimicked by CO gas. The metal carbonyl Ru(CO)3Cl(glycinate) (CORM-3) is a novel, potent antimicrobial agent. Here, we established its mode of action. CORM-3 inhibits respiration in several bacterial and yeast pathogens. In anoxic Escherichia coli suspensions, CORM-3 first stimulates, then inhibits respiration, but much higher concentrations of CORM-3 than of a classic protonophore are required for stimulation. Proton translocation measurements (H(+)/O quotients, i.e., H(+) extrusion on pulsing anaerobic cells with O2) show that respiratory stimulation cannot be attributed to true "uncoupling," that is, dissipation of the protonmotive force, or to direct stimulation of oxidase activity. Our data are consistent with CORM-3 facilitating the electrogenic transmembrane movement of K(+) (or Na(+)), causing a stimulation of respiration and H(+) pumping to compensate for the transient drop in membrane potential (ΔΨ). The effects on respiration are not mimicked by CO gas or control Ru compounds that do not release CO. Inhibition of respiration and loss of bacterial viability elicited by CORM-3 are reversible by white light, unambiguously identifying heme-containing oxidase(s) as target(s). This is the most complete study to date of the antimicrobial action of a CO-RM. Noteworthy are the demonstration of respiratory stimulation, electrogenic ion transport, and photosensitive activity, establishing terminal oxidases and ion transport as primary targets. CORM-3 has multifaceted effects: increased membrane permeability, inhibition of terminal oxidases, and perhaps other unidentified mechanisms underlie its effectiveness in tackling microbial pathogenesis.

  14. Development of antimicrobial coating by later-by-layer dip coating of chlorhexidine-loaded micelles.

    Science.gov (United States)

    Tambunlertchai, Supreeda; Srisang, Siriwan; Nasongkla, Norased

    2017-06-01

    Layer-by-layer (LbL) dip coating, accompanying with the use of micelle structure, allows hydrophobic molecules to be coated on medical devices' surface via hydrogen bonding interaction. In addition, micelle structure also allows control release of encapsulated compound. In this research, we investigated methods to coat and maximize the amount of chlorhexidine (CHX) on silicone surface through LbL dip coating method utilizing hydrogen bonding interaction between PEG on micelle corona and PAA. The number of coated cycles was varied in the process and 90 coating cycles provided the maximum amount of CHX loaded onto the surface. In addition, pre-coating the surface with PAA enhanced the amount of coated CHX by 20%. Scanning electron microscope (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) were used to validate and characterize the coating. For control release aspect, the coated film tended to disrupt at physiological condition; hence chemical crosslinking was performed to minimize the disruption and maximize the release time. Chemical crosslinking at pH 2.5 and 4.5 were performed in the process. It was found that chemical crosslinking could help extend the release period up to 18 days. This was significantly longer when compared to the non-crosslinking silicone tube that could only prolong the release for 5 days. In addition, chemical crosslinking at pH 2.5 gave higher and better initial burst release, release period and antimicrobial properties than that of pH 4.5 or the normal used pH for chemical crosslinking process.

  15. Feleucin-BO1: a novel antimicrobial non-apeptide amide from the skin secretion of the toad, Bombina orientalis, and design of a potent broad-spectrum synthetic analogue, feleucin-K3.

    Science.gov (United States)

    Hou, Xiaojuan; Du, Qiang; Li, Renjie; Zhou, Mei; Wang, Hui; Wang, Lei; Guo, Can; Chen, Tianbao; Shaw, Chris

    2015-03-01

    Feleucins-BV1 and -BV2 are recently described prototypes of a novel antimicrobial non-apeptide (AMP) family identified in the skin secretion of the bombinid toad, Bombina variegata. They are encoded on different precursors that also encode a novel bombinin. Here we describe the identification of feleucin-BO1 (FLGLLGSLLamide) which is co-encoded with a different novel bombinin, named feleucin precursor-associated bombinin (FPA-bombinin-BO), from the skin secretion of Bombina orientalis. Synthetic feleucin-BO1 displayed activity against a reference Gram-positive bacterium. Staphylococcus aureus (MIC 34 μm) but was inactive (> 250 μm) against the Gram-negative bacterium, Escherichia coli, and the yeast, Candida albicans. This pattern of activity was similar to that of the prototypes. Design and synthesis of a cationicity-enhanced analogue, feleucin-K3 (F-K3), in which the amino acid residues at positions 3 (G), 6 (G) and 7 (S) of feleucin-BO1 were substituted with Lys (K) residues, resulted in a peptide with significantly enhanced potency and spectrum of activity. The MICs of F-K3 against the reference micro-organisms were 7 μm (S. aureus), 14 μm (E. coli) and 7 μm (C. albicans). These data indicate that the skin secretions of amphibians can continue to provide novel peptide templates for the rational design of analogues with possible therapeutic utility. © 2014 John Wiley & Sons A/S.

  16. Viable adhered Staphylococcus aureus highly reduced on novel antimicrobial sutures using chlorhexidine and octenidine to avoid surgical site infection (SSI)

    Science.gov (United States)

    Schneider, Jochen; Harrasser, Norbert; Tübel, Jutta; Mühlhofer, Heinrich; Pförringer, Dominik; von Deimling, Constantin; Foehr, Peter; Kiefel, Barbara; Krämer, Christina; Stemberger, Axel; Schieker, Matthias

    2018-01-01

    Background Surgical sutures can promote migration of bacteria and thus start infections. Antiseptic coating of sutures may inhibit proliferation of adhered bacteria and avoid such complications. Objectives This study investigated the inhibition of viable adhering bacteria on novel antimicrobially coated surgical sutures using chlorhexidine or octenidine, a critical factor for proliferation at the onset of local infections. The medical need, a rapid eradication of bacteria in wounds, can be fulfilled by a high antimicrobial efficacy during the first days after wound closure. Methods As a pretesting on antibacterial efficacy against relevant bacterial pathogens a zone of inhibition assay was conducted with middle ranged concentrated suture coatings (22 μg/cm). For further investigation of adhering bacteria in detail the most clinically relevant Staphylococcus aureus (ATCC®49230™) was used. Absorbable braided sutures were coated with chlorhexidine-laurate, chlorhexidine-palmitate, octenidine-laurate, and octenidine-palmitate. Each coating type resulted in 11, 22, or 33 μg/cm drug content on sutures. Scanning electron microscopy (SEM) was performed once to inspect the coating quality and twice to investigate if bacteria have colonized on sutures. Adhesion experiments were assessed by exposing coated sutures to S. aureus suspensions for 3 h at 37°C. Subsequently, sutures were sonicated and the number of viable bacteria released from the suture surface was determined. Furthermore, the number of viable planktonic bacteria was measured in suspensions containing antimicrobial sutures. Commercially available sutures without drugs (Vicryl®, PGA Resorba®, and Gunze PGA), as well as triclosan-containing Vicryl® Plus were used as control groups. Results Zone of inhibition assay documented a multispecies efficacy of novel coated sutures against tested bacterial strains, comparable to most relevant S. aureus over 48 hours. SEM pictures demonstrated uniform layers on

  17. Chlorhexidine in cosmetic products

    DEFF Research Database (Denmark)

    Opstrup, Morten Schjørring; Johansen, Jeanne Duus; Bossi, Rossana

    2015-01-01

    or an antimicrobial agent in cosmetic products at a concentration up to 0.3%, as set by the European Cosmetics Directive (now Regulations). OBJECTIVES: To identify cosmetic product types containing chlorhexidine, and to measure the concentration of chlorhexidine in selected products. METHODS: Between February 2013...... and April 2013, we checked for chlorhexidine in cosmetic products in 14 supermarkets, one hairdressing salon and one beauty and retail store in Copenhagen, Denmark by reading the ingredient labels. The chlorhexidine concentration was measured in 10 selected products by high-performance liquid chromatography...... concentrations were 0.01-0.15%. CONCLUSIONS: We found chlorhexidine in various cosmetic product types, predominantly aimed at females, and in hair products. The measured chlorhexidine concentrations were all within the permitted limit. The relevance for allergic sensitization should be further explored....

  18. Synthetic histatin analogues with broad-spectrum antimicrobial activity.

    OpenAIRE

    Helmerhorst, E J; Van't Hof, W; Veerman, E C; Simoons-Smit, I; Nieuw Amerongen, A V

    1997-01-01

    Histatins are salivary histidine-rich cationic peptides, ranging from 7 to 38 amino acid residues in length, that exert a potent killing effect in vitro on Candida albicans. Starting from the C-terminal fungicidal domain of histatin 5 (residues 11-24, called dh-5) a number of substitution analogues were chemically synthesized to study the effect of amphipathicity of the peptide in helix conformation on candidacidal activity. Single substitutions in dh-5 at several positions did not have any e...

  19. Broad Spectrum Sanitizing Wipes with Food Additives, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcide proposes to develop novel multipurpose non-toxic sanitizing wipes that are aqueous based, have shelf life of 3-5 years, have broad spectrum microbicidal...

  20. Comparison of the Antimicrobial Effect of Chlorhexidine and Saline for Irrigating a Contaminated Open Fracture Model

    Science.gov (United States)

    2012-12-01

    bladder irrigation fluid,10 and periodontal rinse.11 Interestingly, despite its reputation as an effective antiseptic with low toxicity and its...treating compound fracture, abscess , and so forth; with observations on the conditions of suppuration. Lancet. 1867; 89:326, 357, 387, 507. 2. Browning...topical application of chlorhexidine on the development of dental plaque and gingivitis in man. J Periodontal Res. 1970;5:79–83. J Orthop Trauma

  1. In vitro antimicrobial activity of a commercial ear antiseptic containing chlorhexidine and Tris-EDTA.

    Science.gov (United States)

    Guardabassi, Luca; Ghibaudo, Giovanni; Damborg, Peter

    2010-06-01

    Minimum bactericidal concentrations (MBCs) of a commercial ear antiseptic containing chlorhexidine 0.15% and Tris-EDTA (Otodine) were determined by broth microdilution for 150 isolates representing the most common pathogens associated with canine otitis. The microorganisms were classified into three groups according to their levels of susceptibility. The most susceptible group included Staphylococcus pseudintermedius, Malassezia pachydermatis, Streptococcus canis and Corynebacterium auriscanis, which were generally killed by 1 : 64 dilution of the antiseptic product (MBC = 23/0.8 microg/mL of chlorhexidine/Tris-EDTA). The most resistant organism was Proteus mirabilis, which survived up to 1 : 8 dilution of the product (MBC = 375/12 microg/mL). Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus displayed intermediate MBCs ranging between 188/6 and 47/1.5 microg/mL. Interestingly, S. pseudintermedius was more susceptible than S. aureus, and no significant difference was observed between meticillin-resistant and meticillin-susceptible isolates within each species, indicating that antiseptic use is unlikely to co-select for meticillin resistance. Although the concentrations required for killing (MBCs) varied considerably with microorganism type, the combination of chlorhexidine 0.15% and Tris-EDTA was active against all the pathogens most commonly involved in canine otitis.

  2. Antimicrobial activity of Chlorhexidine, Peracetic acid and Sodium hypochlorite/etidronate irrigant solutions against Enterococcus faecalis biofilms.

    Science.gov (United States)

    Arias-Moliz, M T; Ordinola-Zapata, R; Baca, P; Ruiz-Linares, M; García García, E; Hungaro Duarte, M A; Monteiro Bramante, C; Ferrer-Luque, C M

    2015-12-01

    To evaluate the antimicrobial effect of 2.5% sodium hypochlorite alone (NaOCl) and associated with 9% HEBP (NaOCl/HEBP), 2% peracetic acid (PAA) and 2% chlorhexidine (CHX), on the viability of Enterococcus faecalis biofilms attached to dentine. Biofilms of E. faecalis were grown on the surface of dentine blocks for 5 days and then exposed to the irrigating solutions for 3 min. Distilled water was used as the control. The total biovolume and the percentage of dead cells of the infected dentine were measured by means of confocal microscopy and the live/dead technique. Nonparametric tests were used to determine statistical differences (P < 0.05). NaOCl and the NaOCl/HEBP mixture were associated with a significantly greater percentage of dead cells, followed by PAA (P < 0.05). No significant antimicrobial effect of CHX was observed in comparison with the control group. Total biovolume decreased significantly in NaOCl, NaOCl/HEBP and PAA solutions in comparison with the CHX and control groups. NaOCl alone or associated with HEBP were the most effective irrigant solutions in dissolving and killing E. faecalis biofilms. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

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

    Directory of Open Access Journals (Sweden)

    Dias AP

    2018-04-01

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

  4. Comparison of antimicrobial effects of titanium tetrafluoride, chlorhexidine, xylitol and sodium fluoride on streptococcus mutans: An in-vitro study.

    Science.gov (United States)

    Eskandarian, Tahereh; Motamedifar, Mohammad; Arasteh, Peyman; Eghbali, Seyed Sajad; Adib, Ali; Abdoli, Zahra

    2017-03-01

    No studies have yet documented the bactericidal effects of TiF4, and its role in the treatment of dental caries, and no definite protocol has been introduced to regulate its use. The aim of this study was to determine the antimicrobial/bactericidal effects of TiF4 on Streptococcus Mutans ( S. Mutans ) and to compare it with chlorhexidine (Chx), sodium fluoride (NaF) and xylitol. This study was conducted at the Shiraz University of Medical Sciences microbiology laboratory during March 2015 to September 2015. In this in-vitro study, first a bacterial suspension was prepared and adjusted to a 0.5 McFarland standard (equivalent to 1×10 8 CFU/ml). The minimal inhibitory concentration (MIC) and minimal bactericidal concentrations (MBC) of TiF4, Chx, NaF and xylitol were assessed using broth microdilution assay and disk diffusion methods. In order to neutralize the acidic nature of TiF4, we used a sodium hydroxide preparation to obtain a pH of 7.2 and repeated all of the previous tests with the neutralized TiF4 solution. We reported the final results as percentages where appropriate. The MIC of TiF4, NaF and Chx for S. Mutans were 12.5%, 12.5% and 6.25%, respectively. At a concentration of 12.5% the inhibition zone diameters were 9 mm, 15mm and 14mm for TiF4, NaF and Chx, respectively. The MBC was 25%, 12.5% and 12.5% for TiF4, NaF and Chx, respectively. Xylitol failed to show any bactericidal or growth inhibitory effect in all of its concentrations. When we repeated the tests with an adjusted pH, identical results were obtained. TiF4 solutions have anti-growth and bactericidal effects on S. Mutans at a concentration of 12.5% which is comparable with chlorhexidine and NaF, indicating the possible use of this solution in dental practice as an anti-cariogenic agent, furthermore the antimicrobial activity is unaffected by pH of the environment.

  5. Identification and Structural Characterization of Naturally-Occurring Broad-Spectrum Cyclic Antibiotics Isolated from Paenibacillus

    Science.gov (United States)

    Knolhoff, Ann M.; Zheng, Jie; McFarland, Melinda A.; Luo, Yan; Callahan, John H.; Brown, Eric W.; Croley, Timothy R.

    2015-08-01

    The rise of antimicrobial resistance necessitates the discovery and/or production of novel antibiotics. Isolated strains of Paenibacillus alvei were previously shown to exhibit antimicrobial activity against a number of pathogens, such as E. coli, Salmonella, and methicillin-resistant Staphylococcus aureus (MRSA). The responsible antimicrobial compounds were isolated from these Paenibacillus strains and a combination of low and high resolution mass spectrometry with multiple-stage tandem mass spectrometry was used for identification. A group of closely related cyclic lipopeptides was identified, differing primarily by fatty acid chain length and one of two possible amino acid substitutions. Variation in the fatty acid length resulted in mass differences of 14 Da and yielded groups of related MSn spectra. Despite the inherent complexity of MS/MS spectra of cyclic compounds, straightforward analysis of these spectra was accomplished by determining differences in complementary product ion series between compounds that differ in molecular weight by 14 Da. The primary peptide sequence assignment was confirmed through genome mining; the combination of these analytical tools represents a workflow that can be used for the identification of complex antibiotics. The compounds also share amino acid sequence similarity to a previously identified broad-spectrum antibiotic isolated from Paenibacillus. The presence of such a wide distribution of related compounds produced by the same organism represents a novel class of broad-spectrum antibiotic compounds.

  6. The precipitation synthesis of broad-spectrum UV absorber nanoceria

    International Nuclear Information System (INIS)

    Nurhasanah, Iis; Sutanto, Heri; Puspaningrum, Nurul Wahyu

    2013-01-01

    In this paper the possibility of nanoceria as broad-spectrum UV absorber was evaluated. Nanoceria were synthesized by precipitation process from cerium nitrate solution and ammonium hydroxide as precipitant agent. Isopropanol was mixed with water as solvent to prevent hard agglomeration. The structure of resulting nanoceria was characterized by x-ray diffractometer (XRD). The transparency in the visible light and efficiency of protection in UV A region were studied using ultraviolet-visible (UV - Vis) spectrophotometer. The results show that nanoceria possess good tranparency in visible light and high UV light absorption. The critical absorption wavelenght of 368 nm was obtained which is desirable for excellent broad-spectrum protection absorbers. Moreover, analysis of photodegradation nanoceria to methylene blue solution shows poor photocatalytic activity. It indicates that nanoceria suitable for used as UV absorber in personal care products

  7. Broad spectrum antiangiogenic treatment for ocular neovascular diseases.

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    Ofra Benny

    2010-09-01

    Full Text Available Pathological neovascularization is a hallmark of late stage neovascular (wet age-related macular degeneration (AMD and the leading cause of blindness in people over the age of 50 in the western world. The treatments focus on suppression of choroidal neovascularization (CNV, while current approved therapies are limited to inhibiting vascular endothelial growth factor (VEGF exclusively. However, this treatment does not address the underlying cause of AMD, and the loss of VEGF's neuroprotective can be a potential side effect. Therapy which targets the key processes in AMD, the pathological neovascularization, vessel leakage and inflammation could bring a major shift in the approach to disease treatment and prevention. In this study we have demonstrated the efficacy of such broad spectrum antiangiogenic therapy on mouse model of AMD.Lodamin, a polymeric formulation of TNP-470, is a potent broad-spectrum antiangiogenic drug. Lodamin significantly reduced key processes involved in AMD progression as demonstrated in mice and rats. Its suppressive effects on angiogenesis, vascular leakage and inflammation were studied in a wide array of assays including; a Matrigel, delayed-type hypersensitivity (DTH, Miles assay, laser-induced CNV and corneal micropocket assay. Lodamin significantly suppressed the secretion of various pro-inflammatory cytokines in the CNV lesion including monocyte chemotactic protein-1 (MCP-1/Ccl2. Importantly, Lodamin was found to regress established CNV lesions, unlike soluble fms-like tyrosine kinase-1 (sFlk-1. The drug was found to be safe in mice and have little toxicity as demonstrated by electroretinography (ERG assessing retinal and by histology.Lodamin, a polymer formulation of TNP-470, was identified as a first in its class, broad-spectrum antiangiogenic drug that can be administered orally or locally to treat corneal and retinal neovascularization. Several unique properties make Lodamin especially beneficial for ophthalmic

  8. Antimicrobial activity of Calendula officinalis, Camellia sinensis and chlorhexidine against the adherence of microorganisms to sutures after extraction of unerupted third molars

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    Raquel Lourdes Faria

    2011-10-01

    Full Text Available OBJECTIVE: The objective of this study was to compare the antimicrobial effect of mouthwashes containing Calendula officinalis L., Camellia sinensis (L. Kuntze and 0.12% chlorhexidine digluconate on the adherence of microorganisms to suture materials after extraction of unerupted third molars. MATERIAL AND METHODS: Eighteen patients with unerupted maxillary third molars indicated for extraction were selected (n=6 per mouthwash. First, the patients were subjected to extraction of the left tooth and instructed not to use any type of antiseptic solution at the site of surgery (control group. After 15 days, the right tooth was extracted and the patients were instructed to use the Calendula officinalis, Camellia sinensis or chlorhexidine mouthwash during 1 week (experimental group. For each surgery, the sutures were removed on postoperative day 7 and placed in sterile phosphate-buffered saline. Next, serial dilutions were prepared and seeded onto different culture media for the growth of the following microorganisms: blood agar for total microorganism growth; Mitis Salivarius bacitracin sucrose agar for mutans group streptococci; mannitol agar for Staphylococcus spp.; MacConkey agar for enterobacteria and Pseudomonas spp., and Sabouraud dextrose agar containing chloramphenicol for Candida spp. The plates were incubated during 24-48 h at 37ºC for microorganism count (CFU/mL. RESULTS: The three mouthwashes tested reduced the number of microorganisms adhered to the sutures compared to the control group. However, significant differences between the control and experimental groups were only observed for the mouthwash containing 0.12% chlorhexidine digluconate. CONCLUSIONS: Calendula officinalis L. and Camellia sinensis (L. Kuntze presented antimicrobial activity against the adherence of microorganisms to sutures but were not as efficient as chlorhexidine digluconate.

  9. Comparative evaluation of the antimicrobial efficacy of MTAD, oxytetracycline, sodium hypochlorite and chlorhexidine against Enterococcus faecalis: An ex-vivo study

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    Rakesh Mittal

    2012-01-01

    Full Text Available Objectives: To evaluate and compare the antibacterial efficiency of MTAD, Oxytetracycline, 5% NaOCl, and 2% chlorhexidine when used as root canal irrigants against Enterococcus faecalis. Materials and Methods: Fifty extracted human single rooted anterior teeth were selected. The decoronated sterilized root samples were infected with 10μl of 24 hours pure culture suspension of E. faecalis for 48 hours except for 10 teeth in negative control group (Group V. The test samples were divided into four groups (n = 10 as: Group I- 5% Sodium Hypochlorite, Group II- MTAD, Group III- Oxytetracycline and Group IV- 2% Chlorhexidine. The root canals were instrumented while using respective root canal irrigant solution. The bacterial cultures were taken from each root canal and colony forming units were counted on agar plates. The data was statistically analyzed. Results: It was observed that Group-III (Oxytetracycline showed the maximum antibacterial efficacy against E. faecalis followed by Group II (MTAD, Group IV (2% Chlorhexidine, Group I (5% Sodium hypochlorite. Conclusion: Oxytetracycline has a great potential as a root canal irrigating agent because of its superior antimicrobial efficacy against E. faecalis, easy availability and cost effectiveness.

  10. Surveillance of broad-spectrum antibiotic prescription in Singaporean hospitals: a 5-year longitudinal study.

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    Yi-Xin Liew

    Full Text Available BACKGROUND: Inappropriate prescription of antibiotics may contribute towards higher levels antimicrobial resistance. A key intervention for improving appropriate antibiotic prescription is surveillance of prescription. This paper presents the results of a longitudinal surveillance of broad-spectrum antibiotic prescription in 5 public-sector hospitals in Singapore from 2006 to 2010. METHODOLOGY/PRINCIPAL FINDINGS: Quarterly antibiotic prescription data were obtained and converted to defined daily doses (DDDs per 1,000 inpatient-days. The presence of significant trends in antibiotic prescription over time for both individual and combined hospitals was tested by regression analysis and corrected for autocorrelation between time-points. Excluding fluoroquinolones, there was a significant increase in prescription of all monitored antibiotics from an average of 233.12 defined daily doses (DDD/1,000 inpatient-days in 2006 to 254.38 DDD/1,000 inpatient-days in 2010 (Coefficient = 1.13, 95%CI: 0.16-2.09, p = 0.025. Increasing utilization of carbapenems, piperacillin/tazobactam, and Gram-positive agents were seen in the majority of the hospitals, while cephalosporins were less prescribed over time. The combined expenditure for 5 hospitals increased from USD9.9 million in 2006 to USD16.7 million in 2010. CONCLUSIONS/SIGNIFICANCE: The rate of prescription of broad-spectrum antibiotics in Singaporean hospitals is much higher compared to those of European hospitals. This may be due to high rates of antimicrobial resistance. The increase in expenditure on monitored antibiotics over the past 5 years outstripped the actual increase in DDD/1,000 inpatient-days of antibiotics prescribed. Longitudinal surveillance of antibiotic prescription on a hospital and countrywide level is important for detecting trends for formulating interventions or policies. Further research is needed to understand the causes for the various prescription trends and to act on these where

  11. A Broad-Spectrum Inhibitor of CRISPR-Cas9.

    Science.gov (United States)

    Harrington, Lucas B; Doxzen, Kevin W; Ma, Enbo; Liu, Jun-Jie; Knott, Gavin J; Edraki, Alireza; Garcia, Bianca; Amrani, Nadia; Chen, Janice S; Cofsky, Joshua C; Kranzusch, Philip J; Sontheimer, Erik J; Davidson, Alan R; Maxwell, Karen L; Doudna, Jennifer A

    2017-09-07

    CRISPR-Cas9 proteins function within bacterial immune systems to target and destroy invasive DNA and have been harnessed as a robust technology for genome editing. Small bacteriophage-encoded anti-CRISPR proteins (Acrs) can inactivate Cas9, providing an efficient off switch for Cas9-based applications. Here, we show that two Acrs, AcrIIC1 and AcrIIC3, inhibit Cas9 by distinct strategies. AcrIIC1 is a broad-spectrum Cas9 inhibitor that prevents DNA cutting by multiple divergent Cas9 orthologs through direct binding to the conserved HNH catalytic domain of Cas9. A crystal structure of an AcrIIC1-Cas9 HNH domain complex shows how AcrIIC1 traps Cas9 in a DNA-bound but catalytically inactive state. By contrast, AcrIIC3 blocks activity of a single Cas9 ortholog and induces Cas9 dimerization while preventing binding to the target DNA. These two orthogonal mechanisms allow for separate control of Cas9 target binding and cleavage and suggest applications to allow DNA binding while preventing DNA cutting by Cas9. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Application of broad-spectrum resequencing microarray for genotyping rhabdoviruses.

    Science.gov (United States)

    Dacheux, Laurent; Berthet, Nicolas; Dissard, Gabriel; Holmes, Edward C; Delmas, Olivier; Larrous, Florence; Guigon, Ghislaine; Dickinson, Philip; Faye, Ousmane; Sall, Amadou A; Old, Iain G; Kong, Katherine; Kennedy, Giulia C; Manuguerra, Jean-Claude; Cole, Stewart T; Caro, Valérie; Gessain, Antoine; Bourhy, Hervé

    2010-09-01

    The rapid and accurate identification of pathogens is critical in the control of infectious disease. To this end, we analyzed the capacity for viral detection and identification of a newly described high-density resequencing microarray (RMA), termed PathogenID, which was designed for multiple pathogen detection using database similarity searching. We focused on one of the largest and most diverse viral families described to date, the family Rhabdoviridae. We demonstrate that this approach has the potential to identify both known and related viruses for which precise sequence information is unavailable. In particular, we demonstrate that a strategy based on consensus sequence determination for analysis of RMA output data enabled successful detection of viruses exhibiting up to 26% nucleotide divergence with the closest sequence tiled on the array. Using clinical specimens obtained from rabid patients and animals, this method also shows a high species level concordance with standard reference assays, indicating that it is amenable for the development of diagnostic assays. Finally, 12 animal rhabdoviruses which were currently unclassified, unassigned, or assigned as tentative species within the family Rhabdoviridae were successfully detected. These new data allowed an unprecedented phylogenetic analysis of 106 rhabdoviruses and further suggest that the principles and methodology developed here may be used for the broad-spectrum surveillance and the broader-scale investigation of biodiversity in the viral world.

  13. Application of Broad-Spectrum Resequencing Microarray for Genotyping Rhabdoviruses▿

    Science.gov (United States)

    Dacheux, Laurent; Berthet, Nicolas; Dissard, Gabriel; Holmes, Edward C.; Delmas, Olivier; Larrous, Florence; Guigon, Ghislaine; Dickinson, Philip; Faye, Ousmane; Sall, Amadou A.; Old, Iain G.; Kong, Katherine; Kennedy, Giulia C.; Manuguerra, Jean-Claude; Cole, Stewart T.; Caro, Valérie; Gessain, Antoine; Bourhy, Hervé

    2010-01-01

    The rapid and accurate identification of pathogens is critical in the control of infectious disease. To this end, we analyzed the capacity for viral detection and identification of a newly described high-density resequencing microarray (RMA), termed PathogenID, which was designed for multiple pathogen detection using database similarity searching. We focused on one of the largest and most diverse viral families described to date, the family Rhabdoviridae. We demonstrate that this approach has the potential to identify both known and related viruses for which precise sequence information is unavailable. In particular, we demonstrate that a strategy based on consensus sequence determination for analysis of RMA output data enabled successful detection of viruses exhibiting up to 26% nucleotide divergence with the closest sequence tiled on the array. Using clinical specimens obtained from rabid patients and animals, this method also shows a high species level concordance with standard reference assays, indicating that it is amenable for the development of diagnostic assays. Finally, 12 animal rhabdoviruses which were currently unclassified, unassigned, or assigned as tentative species within the family Rhabdoviridae were successfully detected. These new data allowed an unprecedented phylogenetic analysis of 106 rhabdoviruses and further suggest that the principles and methodology developed here may be used for the broad-spectrum surveillance and the broader-scale investigation of biodiversity in the viral world. PMID:20610710

  14. Broad spectrum microarray for fingerprint-based bacterial species identification

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    Frey Jürg E

    2010-02-01

    Full Text Available Abstract Background Microarrays are powerful tools for DNA-based molecular diagnostics and identification of pathogens. Most target a limited range of organisms and are based on only one or a very few genes for specific identification. Such microarrays are limited to organisms for which specific probes are available, and often have difficulty discriminating closely related taxa. We have developed an alternative broad-spectrum microarray that employs hybridisation fingerprints generated by high-density anonymous markers distributed over the entire genome for identification based on comparison to a reference database. Results A high-density microarray carrying 95,000 unique 13-mer probes was designed. Optimized methods were developed to deliver reproducible hybridisation patterns that enabled confident discrimination of bacteria at the species, subspecies, and strain levels. High correlation coefficients were achieved between replicates. A sub-selection of 12,071 probes, determined by ANOVA and class prediction analysis, enabled the discrimination of all samples in our panel. Mismatch probe hybridisation was observed but was found to have no effect on the discriminatory capacity of our system. Conclusions These results indicate the potential of our genome chip for reliable identification of a wide range of bacterial taxa at the subspecies level without laborious prior sequencing and probe design. With its high resolution capacity, our proof-of-principle chip demonstrates great potential as a tool for molecular diagnostics of broad taxonomic groups.

  15. Discovery of potent broad spectrum antivirals derived from marine actinobacteria.

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    Avi Raveh

    Full Text Available Natural products provide a vast array of chemical structures to explore in the discovery of new medicines. Although secondary metabolites produced by microbes have been developed to treat a variety of diseases, including bacterial and fungal infections, to date there has been limited investigation of natural products with antiviral activity. In this report, we used a phenotypic cell-based replicon assay coupled with an iterative biochemical fractionation process to identify, purify, and characterize antiviral compounds produced by marine microbes. We isolated a compound from Streptomyces kaviengensis, a novel actinomycetes isolated from marine sediments obtained off the coast of New Ireland, Papua New Guinea, which we identified as antimycin A1a. This compound displays potent activity against western equine encephalitis virus in cultured cells with half-maximal inhibitory concentrations of less than 4 nM and a selectivity index of greater than 550. Our efforts also revealed that several antimycin A analogues display antiviral activity, and mechanism of action studies confirmed that these Streptomyces-derived secondary metabolites function by inhibiting the cellular mitochondrial electron transport chain, thereby suppressing de novo pyrimidine synthesis. Furthermore, we found that antimycin A functions as a broad spectrum agent with activity against a wide range of RNA viruses in cultured cells, including members of the Togaviridae, Flaviviridae, Bunyaviridae, Picornaviridae, and Paramyxoviridae families. Finally, we demonstrate that antimycin A reduces central nervous system viral titers, improves clinical disease severity, and enhances survival in mice given a lethal challenge with western equine encephalitis virus. Our results provide conclusive validation for using natural product resources derived from marine microbes as source material for antiviral drug discovery, and they indicate that host mitochondrial electron transport is a viable

  16. The broad spectrum revisited: evidence from plant remains.

    Science.gov (United States)

    Weiss, Ehud; Wetterstrom, Wilma; Nadel, Dani; Bar-Yosef, Ofer

    2004-06-29

    The beginning of agriculture is one of the most important developments in human history, with enormous consequences that paved the way for settled life and complex society. Much of the research on the origins of agriculture over the last 40 years has been guided by Flannery's [Flannery, K. V. (1969) in The Domestication and Exploitation of Plants and Animals, eds. Ucko, P. J. & Dimbleby, G. W. (Duckworth, London), pp. 73-100] "broad spectrum revolution" (BSR) hypothesis, which posits that the transition to farming in southwest Asia entailed a period during which foragers broadened their resource base to encompass a wide array of foods that were previously ignored in an attempt to overcome food shortages. Although these resources undoubtedly included plants, nearly all BSR hypothesis-inspired research has focused on animals because of a dearth of Upper Paleolithic archaeobotanical assemblages. Now, however, a collection of >90,000 plant remains, recently recovered from the Stone Age site Ohalo II (23,000 B.P.), Israel, offers insights into the plant foods of the late Upper Paleolithic. The staple foods of this assemblage were wild grasses, pushing back the dietary shift to grains some 10,000 years earlier than previously recognized. Besides the cereals (wild wheat and barley), small-grained grasses made up a large component of the assemblage, indicating that the BSR in the Levant was even broader than originally conceived, encompassing what would have been low-ranked plant foods. Over the next 15,000 years small-grained grasses were gradually replaced by the cereals and ultimately disappeared from the Levantine diet.

  17. Steps toward broad-spectrum therapeutics: discovering virulence-associated genes present in diverse human pathogens

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    de Rochefort Anna

    2009-10-01

    Full Text Available Abstract Background New and improved antimicrobial countermeasures are urgently needed to counteract increased resistance to existing antimicrobial treatments and to combat currently untreatable or new emerging infectious diseases. We demonstrate that computational comparative genomics, together with experimental screening, can identify potential generic (i.e., conserved across multiple pathogen species and novel virulence-associated genes that may serve as targets for broad-spectrum countermeasures. Results Using phylogenetic profiles of protein clusters from completed microbial genome sequences, we identified seventeen protein candidates that are common to diverse human pathogens and absent or uncommon in non-pathogens. Mutants of 13 of these candidates were successfully generated in Yersinia pseudotuberculosis and the potential role of the proteins in virulence was assayed in an animal model. Six candidate proteins are suggested to be involved in the virulence of Y. pseudotuberculosis, none of which have previously been implicated in the virulence of Y. pseudotuberculosis and three have no record of involvement in the virulence of any bacteria. Conclusion This work demonstrates a strategy for the identification of potential virulence factors that are conserved across a number of human pathogenic bacterial species, confirming the usefulness of this tool.

  18. Risk Factors for Emergence of Resistance to Broad-Spectrum Cephalosporins among Enterobacter spp.

    Science.gov (United States)

    Kaye, Keith S.; Cosgrove, Sara; Harris, Anthony; Eliopoulos, George M.; Carmeli, Yehuda

    2001-01-01

    Among 477 patients with susceptible Enterobacter spp., 49 subsequently harbored third-generation cephalosporin-resistant Enterobacter spp. Broad-spectrum cephalosporins were independent risk factors for resistance (relative risk [OR] = 2.3, P = 0.01); quinolone therapy was protective (OR = 0.4, P = 0.03). There were trends toward decreased risk for resistance among patients receiving broad-spectrum cephalosporins and either aminoglycosides or imipenem. Of the patients receiving broad-spectrum cephalosporins, 19% developed resistance. PMID:11502540

  19. Comparative evaluation of the antimicrobial activity of natural extracts of Morinda citrifolia, papain and aloe vera (all in gel formulation), 2% chlorhexidine gel and calcium hydroxide, against Enterococcus faecalis: An in vitro study.

    Science.gov (United States)

    Bhardwaj, Anuj; Ballal, Suma; Velmurugan, Natanasabapathy

    2012-07-01

    A comparative evaluation of the antimicrobial activity of natural extracts of Morinda citrifolia, papain, and aloe vera (all in gel formulations), 2% chlorhexidine gel and calcium hydroxide, against Enterococcus faecalis-an in vitro study. The antimicrobial efficacy was assessed in vitro using dentin shavings collected at 2 depths of 200 and 400 μm. The total colony forming units at the end of 1, 3, and 5 days were assessed. The overall percentage inhibition of bacterial growth (200 and 400 μm depth) was 100% with chlorhexidine gel. This was followed by M. citrifolia gel (86.02%), which showed better antimicrobial efficacy as compared with aloe vera gel (78.9%), papain gel (67.3%), and calcium hydroxide (64.3%). There was no statistical difference between data at 200 and 400 μm depth. Chlorhexidine gel showed the maximum antimicrobial activity against E. faecalis, whereas calcium hydroxide showed the least. Among the natural intracanal medicaments, M. citrifolia gel consistently exhibited good inhibition up to the 5(th) day followed by aloe vera gel and papain gel.

  20. Probing Gallic Acid for Its Broad Spectrum Applications.

    Science.gov (United States)

    Choubey, Sneha; Goyal, Soniya; Varughese, Lesley Rachel; Kumar, Vinod

    2018-03-29

    Gallic acid and its derivatives not only exhibit excellent antioxidant, anticarcinogenic, antimutagenic, antimicrobial properties but also provide protection to the cells against oxidative stress. Gallic acid (3, 4, 5-trihydroxybenzoic acid), a low molecular triphenolic compound has arised as an efficient apoptosis inducing agent. The antimicrobial and other biological properties of gallic acid and its derivatives seemed to be linked with the hydrolysis of ester linkage between gallic acid and polyols like tannins hydrolyzed after ripening of many edible fruits. Gallic acid serves a natural defense mechanism against microbial infections and modulation of immune-responses. The current review updates us with the diverse roles played by gallic acid, its antioxidant potential, action mechanism and more importantly the diverse array of applications in therapeutic and pharmaceutical area. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  1. Role of bronchoalveolar lavage in immunocompromised patients with pneumonia treated with a broad spectrum antibiotic and antifungal regimen

    Science.gov (United States)

    Hohenadel, I; Kiworr, M; Genitsariotis, R; Zeidler, D; Lorenz, J

    2001-01-01

    BACKGROUND—In a retrospective study the value of bronchoalveolar lavage (BAL) in the diagnosis of pneumonia was investigated in 95 immunocompromised patients suffering from haematological disorders and receiving a regimen of broad spectrum antibiotics and antifungal agents (BSAR).
METHODS—With the exception of four afebrile patients, all had fever, raised C reactive protein (CRP) levels, and new infiltrates visible on chest radiography. All patients underwent BAL to identify the organism causing the pneumonia and surveillance cultures were performed regularly for pathogens at different sites. Following classification of the isolates, patients with positive cultures were subdivided into two groups, pathogenic or contaminated. We investigated whether relevant pathogens were cultured only from the BAL fluid and whether they were susceptible to BSAR.
RESULTS—Although 77 of the 95 patients were thrombocytopenic, bleeding during BAL occurred in only 15% of all patients. Ten days after the procedure the fever improved in 88% of patients, radiographic findings improved in 71%, and CRP levels improved in 75% of patients; 22% of patients died within 28 days. Pathologically relevant isolates were found in 65% of all patients. Respiratory pathogens were detected only in the BAL fluid of 29 of the 95 patients (35% Gram positive species, 40% Gram negative species, 11% Mycobacterium, 11% fungi, and 3% cytomegalovirus). In 16 of these 29 patients (55%) the pathogens cultured only from the BAL fluid were resistant to treatment. Pathogens detected only in the BAL fluid were not susceptible to a standard broad spectrum antibiotic and antifungal regimen including teicoplanin, ceftriaxon, tobramycin, and amphotericin B in 12 of the 29 patients (41%).
CONCLUSIONS—Our data suggest that 12 patients were treated with broad spectrum antimicrobial agents which were not directed at the appropriate organism on in vitro sensitivity tests without BAL. BAL is a relatively safe

  2. In vitro antimicrobial activity of sodium hypochlorite, chlorhexidine gluconate and octenidine dihydrochloride in elimination of microorganisms within dentinal tubules of primary and permanent teeth.

    Science.gov (United States)

    Tirali, Resmiye-Ebru; Bodur, Haluk; Ece, Gülden

    2012-05-01

    The aim of this study was to evaluate the effectiveness of different irrigation solutions at different time intervals for the elimination of E. faecalis and C. albicans penetrated into the dentine tubules of primary and permanent teeth in vitro. The 4 mm primary and permanent teeth sections were sterilized and contaminated with a mixture of E. faecalis and C. albicans strains. After the application of different irrigation solutions (Sodium hypochlorite, Chlorhexidine gluconate, Octenidine Dihydrochloride, saline) to the contaminated tooth sections according to study groups, neutralizers were applied for inactivation of the solutions after 30 sec, 1 min and 5 min. Dentine shavings were placed into TSB and 10 µL from each tube was inoculated on agar plates, followed by an incubation period of 24 h at 37°C. The colonies were counted macroscopically. The results were compared by using Kruskal-Wallis and Mann Whitney U tests, with a significance level at pteeth, the most effective one was found as 5-minute application of 0.1% Octenidine Dihydrochloride. The antibacterial effects of the tested solutions on the same time periods against C. albicans revealed no significant difference. There were no statistically significant differences between primary and permanent teeth with respect to the antimicrobial activity of the tested solutions. Moreover, Octenidine Dihydrochloride may be used as an alternative endodontic irrigant.

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

    Science.gov (United States)

    Dias, Ana Paula; Paschoal, Marco Aurélio Benini; Diniz, Rafael Soares; Lage, Lucas Meneses; Gonçalves, Letícia Machado

    2018-01-01

    The objectives of this study were to assess the adherence of Streptococcus mutans biofilms grown over conventional ligature (CL) or self-ligating (SL) metal brackets and their bacterial viability after 0.12% chlorhexidine (CHX) digluconate treatment. The sample consisted of 48 metallic orthodontic brackets divided randomly into two groups: CL (n=24) and SL brackets (n=24). S. mutans biofilms were grown over the bracket surface (96 h) and treated with CHX (positive control) or 0.9% phosphate-buffered saline (PBS) (negative control) for 1 min each. Quantitative analysis was assessed by colony-forming units, and fluorescence microscopy was performed aiming to illustrate the outcomes. The tests were done in triplicate at three different times (n=9). Data were analyzed using ANOVA and Tukey test ( P brackets' biofilm formation, being CL largely colonized compared with SL, which was observed by colony-forming unit counting ( P brackets treated with CHX compared to PBS ( P brackets ( P >0.05). In conclusion, a lower colonization was achieved in SL brackets and S. mutans biofilms were susceptible to CHX treatment to both studied brackets.

  4. Isolation and Characterization of a Broad Spectrum Bacteriocin from Bacillus amyloliquefaciens RX7

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    Kong Boon Lim

    2016-01-01

    Full Text Available We isolated a Bacillus strain, RX7, with inhibitory activity against Listeria monocytogenes from soil and identified it as Bacillus amyloliquefaciens based on 16S rRNA gene sequencing. The inhibitory activity was stable over a wide range of pH and was fully retained after 30 min at 80°C, after which it decreased gradually at higher temperatures. The activity was sensitive to the proteolytic action of α-chymotrypsin, proteinase-K, and trypsin, indicating its proteinaceous nature. This bacteriocin was active against a broad spectrum of bacteria and the fungus Candida albicans. Direct detection of antimicrobial activity on a sodium dodecyl sulfate-polyacrylamide gel suggested an apparent molecular mass of approximately 5 kDa. Ammonium sulfate precipitation and anion-exchange and gel permeation chromatography integrated with reverse phase-high-performance liquid chromatography were used for bacteriocin purification. Automated N-terminal Edman degradation of the purified RX7 bacteriocin recognized the first 15 amino acids as NH2-X-Ala-Trp-Tyr-Asp-Ile-Arg-Lys-Leu-Gly-Asn-Lys-Gly-Ala, where the letter X in the sequence indicates an unknown or nonstandard amino acid. Based on BLAST similarity search and multiple alignment analysis, the obtained partial sequence showed high homology with the two-peptide lantibiotic haloduracin (HalA1 from Bacillus halodurans, although at least two amino acids differed between the sequences. A time-kill study demonstrated a bactericidal mode of action of RX7 bacteriocin.

  5. Comparison of the in vivo antimicrobial effectiveness of sodium hypochlorite and chlorhexidine used as root canal irrigants: a molecular microbiology study.

    Science.gov (United States)

    Rôças, Isabela N; Siqueira, José F

    2011-02-01

    The purpose of this clinical study was to compare the antimicrobial effects of 2.5% sodium hypochlorite (NaOCl) and 0.12% chlorhexidine digluconate (CHX) when used as irrigants during treatment of teeth with apical periodontitis. Forty-seven single-rooted single-canal teeth with necrotic pulps and asymptomatic apical periodontitis were selected for this study according to stringent inclusion/exclusion criteria. Bacterial samples were taken at the baseline (S1) and after (S2) chemomechanical preparation using 2.5% NaOCl (n = 30) or 0.12% CHX (n = 17) as the irrigant. Bacterial, archaeal, and fungal presence was evaluated by broad-range polymerase chain reaction (PCR), whereas bacterial identifications were performed by a closed-ended reverse-capture checkerboard approach targeting 28 candidate endodontic pathogens. All S1 samples were PCR positive for bacterial presence but negative for both archaea and fungi. Both NaOCl- and CHX-based protocols were significantly effective in reducing the bacterial levels and number of taxa. No significant differences were observed between them in all tested parameters including the incidence of negative PCR results in S2 (40% for NaOCl vs 47% for CHX, p = 0.8), reduction in the number of taxa per canal (p = 0.3), and reduction in the bacterial levels (p = 0.07). The most prevalent taxa in S2 samples from the NaOCl group were Propionibacterium acnes, Streptococcus species, Porphyromonas endodontalis, and Selenomonas sputigena. In the CHX group, the most prevalent taxa in S2 were Dialister invisus, Actinomyces israelii, Prevotella baroniae, Propionibacterium acidifaciens, and Streptococcus species. Treatment protocols using irrigation with either NaOCl or CHX succeeded in significantly reducing the the number of bacterial taxa and their levels in infected root canals, with no significant difference between these substances. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  6. Chlorhexidine in endodontics.

    Science.gov (United States)

    Gomes, Brenda P F A; Vianna, Morgana E; Zaia, Alexandre A; Almeida, José Flávio A; Souza-Filho, Francisco J; Ferraz, Caio C R

    2013-01-01

    Chemical auxiliary substances (CAS) are essential for a successful disinfection and cleanness of the root canals, being used during the instrumentation and if necessary, as antimicrobial intracanal medicaments. Different CAS have been proposed and used, among which sodium hypochlorite (NaOCl), chlorhexidine (CHX), 17% EDTA, citric acid, MTAD and 37% phosphoric acid solution. CHX has been used in Endodontics as an irrigating substance or intracanal medicament, as it possesses a wide range of antimicrobial activity, substantivity (residual antimicrobial activity), lower cytotoxicity than NaOCl whilst demonstrating efficient clinical performance, lubricating properties, rheological action (present in the gel presentation, keeping the debris in suspension); it inhibits metalloproteinase, is chemically stable, does not stain cloths, it is odorless, water soluble, among other properties. CHX has been recommended as an alternative to NaOCl, especially in cases of open apex, root resorption, foramen enlargement and root perforation, due to its biocompatibility, or in cases of allergy related to bleaching solutions. The aim of this paper is to review CHX's general use in the medical field and in dentistry; its chemical structure, presentation form and storage; mechanism of action; antimicrobial activity including substantivity, effects on biofilms and endotoxins, effects on coronal and apical microbial microleakage; tissue dissolution ability; interaction with endodontic irrigants; effects on dentin bonding, metalloproteinases and collagen fibrils; its use as intracanal medicament and diffusion into the dentinal tubules; its use as disinfectant agent of obturation cones; other uses in the endodontic therapy; and possible adverse effects, cytotoxicity and genotoxicity.

  7. Factors influencing success of clinical genome sequencing across a broad spectrum of disorders

    DEFF Research Database (Denmark)

    Taylor, Jenny C; Martin, Hilary C; Lise, Stefano

    2015-01-01

    To assess factors influencing the success of whole-genome sequencing for mainstream clinical diagnosis, we sequenced 217 individuals from 156 independent cases or families across a broad spectrum of disorders in whom previous screening had identified no pathogenic variants. We quantified the numb...

  8. IgE-mediated chlorhexidine allergy: a new occupational hazard?

    DEFF Research Database (Denmark)

    Nagendran, Vasantha; Wicking, Jennifer; Ekbote, Anjali

    2009-01-01

    BACKGROUND: Chlorhexidine is an effective antimicrobial agent commonly used in UK hospitals, primarily for skin decontamination. Recent UK infection control guidelines recommend the use of 2% chlorhexidine solution in specific clinical settings, thus increasing chlorhexidine use by health care...... those with possible clinical allergy to come forward for further testing. Diagnosis was based on an appropriate clinical history with positive serum-specific IgE to chlorhexidine and/or positive skin prick testing. RESULTS: Four cases of occupational IgE-mediated allergy to chlorhexidine were identified...... workers (HCWs). Chlorhexidine has been widely reported to cause IgE-mediated allergic reactions (from urticaria and angioedema to anaphylaxis) among patients undergoing surgery/invasive procedures. Despite its widespread use in health care settings, there are no reports of clinically confirmed...

  9. Antimicrobial efficacy of 0·05% cetylpyridinium chloride mouthrinses.

    Science.gov (United States)

    Sreenivasan, P K; Haraszthy, V I; Zambon, J J

    2013-01-01

    This study evaluated the antimicrobial activity of two commercially available 0·05% cetylpyridinium chloride (CPC) mouthrinses with or without alcohol and examined its antimicrobial activity on oral bacterial species including fresh clinical isolates compared to a chlorhexidine mouthrinse and a control fluoride mouthrinse without CPC. Two different approaches were used to evaluate antimicrobial activity. First, the minimum inhibitory concentration (MIC) was determined for each mouthrinse against a panel of 25 micro-organisms including species associated with dental caries, gingivitis and periodontitis. Second, supragingival dental plaque obtained from 15 adults was incubated with the four mouthrinses to evaluate antimicrobial activity on micro-organisms in oral biofilms. Both CPC mouthrinses exhibited lower MIC's, that is, greater antimicrobial activity, against oral Gram-negative bacteria especially periodontal pathogens and species implicated in halitosis such as Aggregatibacter actinomycemcomitans, Campylobacter rectus, Eikenella corrodens, Porphyromonas gingivalis, Prevotella intermedia and Solobacterium moorei than the control mouthrinse. Ex-vivo tests on supragingival plaque micro-organisms demonstrated significantly greater antimicrobial activity by the CPC mouthrinses (>90% killing, P 98% killing, P fluoride mouthrinse. Whilst the chlorhexidine mouthrinse was most effective, mouthrinses containing 0·05% CPC formulated with or without alcohol demonstrated broad-spectrum antimicrobial activity against both laboratory strains and supragingival plaque bacteria compared to a control mouthrinse without CPC. These in vitro and ex-vivo studies provide a biological rationale for previous clinical studies demonstrating the efficacy of CPC mouthrinses in reducing supragingival plaque and plaque-associated gingivitis. © 2012 The Society for Applied Microbiology.

  10. Broad-Spectrum Antibiotic Treatment and Subsequent Childhood Type 1 Diabetes

    DEFF Research Database (Denmark)

    Clausen, Tine D; Bergholt, Thomas; Bouaziz, Olivier

    2016-01-01

    of childhood type 1 diabetes and the potential effect-modification by mode of delivery. MATERIALS AND METHODS: A Danish nationwide cohort study including all singletons born during 1997-2010. End of follow-up by December 2012. Four national registers provided information on antibiotic redemptions, outcome...... and confounders. Redemptions of antibiotic prescriptions during the first two years of life was classified into narrow-spectrum or broad-spectrum antibiotics. Children were followed from age two to fourteen, both inclusive. The risk of type 1 diabetes with onset before the age of 15 years was assessed by Cox...... regression. A total of 858,201 singletons contributed 5,906,069 person-years, during which 1,503 children developed type 1 diabetes. RESULTS: Redemption of broad-spectrum antibiotics during the first two years of life was associated with an increased rate of type 1 diabetes during the following 13 years...

  11. Comparison of Antimicrobial Activity of Chlorhexidine, Coconut Oil, Probiotics, and Ketoconazole on Candida albicans Isolated in Children with Early Childhood Caries: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Beena Shino

    2016-01-01

    Full Text Available Background. Early childhood caries (ECC is associated with early colonisation and high levels of cariogenic microorganisms. With C. albicans being one of those, there is a need to determine the effectiveness of various chemotherapeutic agents against it. The study is aimed at isolating Candida species in children with ECC and at studying the antifungal effect of coconut oil, probiotics, Lactobacillus, and 0.2% chlorhexidine on C. albicans in comparison with ketoconazole. Materials and Methods. Samples were collected using sterile cotton swabs, swabbed on the tooth surfaces from children with ECC of 3 to 6 yrs and streaked on Sabouraud dextrose agar (HI Media plates and incubated in a 5% CO2 enriched atmosphere at 37°C for 24 hours. Candida was isolated and its susceptibility to probiotics, chlorhexidine, ketoconazole, and coconut oil was determined using Disc Diffusion method. Results. The mean zone of inhibition for chlorhexidine was 21.8 mm, whereas for coconut oil it was 16.8 mm, for probiotics it was 13.5 mm, and for ketoconazole it was 22.3 mm. The difference between the groups was not statistically significant (Chi-square value 7.42, P value 0.06. Conclusion. Chlorhexidine and coconut oil have shown significant antifungal activity which is comparable with ketoconazole.

  12. Factors influencing success of clinical genome sequencing across a broad spectrum of disorders

    OpenAIRE

    Taylor, Jenny C; Martin, Hilary C; Lise, Stefano; Broxholme, John; Cazier, Jean-Baptiste; Rimmer, Andy; Kanapin, Alexander; Lunter, Gerton; Fiddy, Simon; Allan, Chris; Aricescu, A. Radu; Attar, Moustafa; Babbs, Christian; Becq, Jennifer; Beeson, David

    2015-01-01

    To assess factors influencing the success of whole genome sequencing for mainstream clinical diagnosis, we sequenced 217 individuals from 156 independent cases across a broad spectrum of disorders in whom prior screening had identified no pathogenic variants. We quantified the number of candidate variants identified using different strategies for variant calling, filtering, annotation and prioritisation. We found that jointly calling variants across samples, filtering against both local and e...

  13. The broad-spectrum antiviral compound ST-669 restricts chlamydial inclusion development and bacterial growth and localizes to host cell lipid droplets within treated cells.

    Science.gov (United States)

    Sandoz, Kelsi M; Valiant, William G; Eriksen, Steven G; Hruby, Dennis E; Allen, Robert D; Rockey, Daniel D

    2014-07-01

    Novel broad-spectrum antimicrobials are a critical component of a strategy for combating antibiotic-resistant pathogens. In this study, we explored the activity of the broad-spectrum antiviral compound ST-669 for activity against different intracellular bacteria and began a characterization of its mechanism of antimicrobial action. ST-669 inhibits the growth of three different species of chlamydia and the intracellular bacterium Coxiella burnetii in Vero and HeLa cells but not in McCoy (murine) cells. The antichlamydial and anti-C. burnetii activity spectrum was consistent with those observed for tested viruses, suggesting a common mechanism of action. Cycloheximide treatment in the presence of ST-669 abrogated the inhibitory effect, demonstrating that eukaryotic protein synthesis is required for tested activity. Immunofluorescence microscopy demonstrated that different chlamydiae grow atypically in the presence of ST-669, in a manner that suggests the compound affects inclusion formation and organization. Microscopic analysis of cells treated with a fluorescent derivative of ST-669 demonstrated that the compound localized to host cell lipid droplets but not to other organelles or the host cytosol. These results demonstrate that ST-669 affects intracellular growth in a host-cell-dependent manner and interrupts proper development of chlamydial inclusions, possibly through a lipid droplet-dependent process. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  14. Data-driven analysis of biomedical literature suggests broad-spectrum benefits of culinary herbs and spices.

    Science.gov (United States)

    Rakhi, N K; Tuwani, Rudraksh; Mukherjee, Jagriti; Bagler, Ganesh

    2018-01-01

    Spices and herbs are key dietary ingredients used across cultures worldwide. Beyond their use as flavoring and coloring agents, the popularity of these aromatic plant products in culinary preparations has been attributed to their antimicrobial properties. Last few decades have witnessed an exponential growth of biomedical literature investigating the impact of spices and herbs on health, presenting an opportunity to mine for patterns from empirical evidence. Systematic investigation of empirical evidence to enumerate the health consequences of culinary herbs and spices can provide valuable insights into their therapeutic utility. We implemented a text mining protocol to assess the health impact of spices by assimilating, both, their positive and negative effects. We conclude that spices show broad-spectrum benevolence across a range of disease categories in contrast to negative effects that are comparatively narrow-spectrum. We also implement a strategy for disease-specific culinary recommendations of spices based on their therapeutic tradeoff against adverse effects. Further by integrating spice-phytochemical-disease associations, we identify bioactive spice phytochemicals potentially involved in their therapeutic effects. Our study provides a systems perspective on health effects of culinary spices and herbs with applications for dietary recommendations as well as identification of phytochemicals potentially involved in underlying molecular mechanisms.

  15. Data-driven analysis of biomedical literature suggests broad-spectrum benefits of culinary herbs and spices

    Science.gov (United States)

    Mukherjee, Jagriti

    2018-01-01

    Spices and herbs are key dietary ingredients used across cultures worldwide. Beyond their use as flavoring and coloring agents, the popularity of these aromatic plant products in culinary preparations has been attributed to their antimicrobial properties. Last few decades have witnessed an exponential growth of biomedical literature investigating the impact of spices and herbs on health, presenting an opportunity to mine for patterns from empirical evidence. Systematic investigation of empirical evidence to enumerate the health consequences of culinary herbs and spices can provide valuable insights into their therapeutic utility. We implemented a text mining protocol to assess the health impact of spices by assimilating, both, their positive and negative effects. We conclude that spices show broad-spectrum benevolence across a range of disease categories in contrast to negative effects that are comparatively narrow-spectrum. We also implement a strategy for disease-specific culinary recommendations of spices based on their therapeutic tradeoff against adverse effects. Further by integrating spice-phytochemical-disease associations, we identify bioactive spice phytochemicals potentially involved in their therapeutic effects. Our study provides a systems perspective on health effects of culinary spices and herbs with applications for dietary recommendations as well as identification of phytochemicals potentially involved in underlying molecular mechanisms. PMID:29813110

  16. Choline and Geranate Deep Eutectic Solvent as a Broad-Spectrum Antiseptic Agent for Preventive and Therapeutic Applications.

    Science.gov (United States)

    Zakrewsky, Michael; Banerjee, Amrita; Apte, Sanjana; Kern, Theresa L; Jones, Mattie R; Sesto, Rico E Del; Koppisch, Andrew T; Fox, David T; Mitragotri, Samir

    2016-06-01

    Antiseptic agents are the primary arsenal to disinfect skin and prevent pathogens spreading within the host as well as into the surroundings; however the Food and Drug Administration published a report in 2015 requiring additional validation of nearly all current antiseptic agents before their continued use can be allowed. This vulnerable position calls for urgent identification of novel antiseptic agents. Recently, the ability of a deep eutectic, Choline And Geranate (CAGE), to treat biofilms of Pseudomonas aeruginosa and Salmonella enterica was demonstrated. Here it is reported that CAGE exhibits broad-spectrum antimicrobial activity against a number of drug-resistant bacteria, fungi, and viruses including clinical isolates of Mycobacterium tuberculosis, Staphylococcus aureus, and Candida albicans as well as laboratory strains of Herpes Simplex Virus. Studies in human keratinocytes and mice show that CAGE affords negligible local or systemic toxicity, and an ≈180-14 000-fold improved efficacy/toxicity ratio over currently used antiseptic agents. Further, CAGE penetrates deep into the dermis and treats pathogens located in deep skin layers as confirmed by the ability of CAGE in vivo to treat Propionibacterium acnes infection. In combination, the results clearly demonstrate CAGE holds promise as a transformative platform antiseptic agent for preventive as well as therapeutic applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Gamma-irradiated scrub typhus immunogens: broad-spectrum immunity with combinations of rickettsial strains

    International Nuclear Information System (INIS)

    Eisenberg, G.H. Jr.; Osterman, J.V.

    1979-01-01

    Scrub typhus immunogens were prepared from Rickettsia tsutsugamushi strains Karp, Kato, Gilliam, Kostival, and Buie by exposing frozen infected yolk sac suspensions to 300 krad of gamma radiation. Mouse protection tests showed that each of the irradiated immunogens protected C3H/HeDub mice against high challenge levels of Karp and Gilliam, but that none of these single-strain immunogens were capable of protecting against all five of the challenge strains. Broad-spectrum protection was achieved by using combinations of three strains of irradiated rickettsiae in a vaccination regimen of three injections at 5-day intervals

  18. Biological activity of sedaxane---a novel broad-spectrum fungicide for seed treatment.

    Science.gov (United States)

    Zeun, Ronald; Scalliet, Gabriel; Oostendorp, Michael

    2013-04-01

    Sedaxane is a new broad-spectrum seed treatment fungicide developed by Syngenta Crop Protection for control of seed- and soil-borne diseases in a broad range of crops. Its physicochemical properties and activity spectrum have been optimised for use as a seed treatment providing both local and systemic protection of the seed and roots of target crops. Sedaxane inhibits respiration by binding to the succinate dehydrogenase complex in the fungal mitochondrium. Its activity spectrum covers seed-borne fungi such as Ustilago nuda, Tilletia caries, Monographella nivalis and Pyrenophora graminea, as well as the soil-borne fungi Rhizoctonia solani, R. cerealis and Typhula incarnata. Under greenhouse conditions, sedaxane showed high levels and consistent protection against U. nuda, P. graminea and Rhizoctonia spp. Under field conditions, efficacy against Rhizoctonia spp. resulted in increased yield compared with the untreated check. Efficacy against snow mould has been shown under very high disease pressure conditions. The combination of sedaxane plus fludioxonil against snow mould can provide resistance management for sustainable use. The broad spectrum and high level of activity in combination with excellent crop tolerance allow the use of sedaxane as a seed treatment in a wide variety of crops. It is a potential tool for precautionary resistance management when combined with other fungicides, especially against pathogens showing a potential for resistance development, such as M. nivalis. © 2012 Society of Chemical Industry.

  19. Nanomedicine for Infectious Disease Applications: Innovation towards Broad-Spectrum Treatment of Viral Infections.

    Science.gov (United States)

    Jackman, Joshua A; Lee, Jaywon; Cho, Nam-Joon

    2016-03-02

    Nanomedicine enables unique diagnostic and therapeutic capabilities to tackle problems in clinical medicine. As multifunctional agents with programmable properties, nanomedicines are poised to revolutionize treatment strategies. This promise is especially evident for infectious disease applications, for which the continual emergence, re-emergence, and evolution of pathogens has proven difficult to counter by conventional approaches. Herein, a conceptual framework is presented that envisions possible routes for the development of nanomedicines as superior broad-spectrum antiviral agents against enveloped viruses. With lipid membranes playing a critical role in the life cycle of medically important enveloped viruses including HIV, influenza, and Ebola, cellular and viral membrane interfaces are ideal elements to incorporate into broad-spectrum antiviral strategies. Examples are presented that demonstrate how nanomedicine strategies inspired by lipid membranes enable a wide range of targeting opportunities to gain control of critical stages in the virus life cycle through either direct or indirect approaches involving membrane interfaces. The capabilities can be realized by enabling new inhibitory functions or improving the function of existing drugs through nanotechnology-enabled solutions. With these exciting opportunities, due attention is also given to the clinical translation of nanomedicines for infectious disease applications, especially as pharmaceutical drug-discovery pipelines demand new routes of innovation. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. In vitro antimicrobial and anti-endotoxin action of Zingiber Officinale as auxiliary chemical and medicament combined to calcium hydroxide and chlorhexidine.

    Science.gov (United States)

    Valera, Marcia Carneiro; Cardoso, Flávia Goulart da Rosa; Maekawa, Lilian Eiko; Camargo, Carlos Henrique Ribeiro; de Oliveira, Luciane Dias; Carvalho, Cláudio Antônio Talge

    2015-01-01

    This study was conducted in vitro to compare the effectiveness of Zingiber Officinale as an auxiliary chemical substance followed by placement of different intra-canal medication in removing endotoxins and cultivable micro-organisms from infected root canals. Seventy-two root canals were contaminated with Enterococcus faecalis, Candida albicans and Escherichia coli for 28 days. After, the teeth were instrumented using Zingiber Officinale and divided into six groups according to the intra-canal medication: chlorhexidine gel; calcium hydroxide + chlorhexidine gel; glycolic ginger extract; calcium hydroxide + glycolic ginger extract; calcium hydroxide + saline solution and saline solution (control). Sample collections were performed after root canal contamination (Baseline; S1), after instrumentation (S2), 7 days after instrumentation (S3), after 14 days with intra-canal medication (S4) and 7 days after removal of intra-canal medication (S5). The results were analyzed by the Kruskal-Wallis and Dunn tests. It was observed that in S2 and S3 there was significant reduction of the micro-organisms and the quantity of endotoxins after instrumentation. In samples S4 and S5 there was complete elimination of micro-organisms and significant reduction of endotoxins. It was concluded that Zingiber Officinale as an auxiliary chemical substance was effective on the micro-organisms tested, yet was unable to eliminate the endotoxins. Similarly, the intra-canal medication were effective on micro-organisms, yet did not completely eliminate the endotoxins.

  1. Development of a broad-spectrum antiviral with activity against Ebola virus.

    Science.gov (United States)

    Aman, M Javad; Kinch, Michael S; Warfield, Kelly; Warren, Travis; Yunus, Abdul; Enterlein, Sven; Stavale, Eric; Wang, Peifang; Chang, Shaojing; Tang, Qingsong; Porter, Kevin; Goldblatt, Michael; Bavari, Sina

    2009-09-01

    We report herein the identification of a small molecule therapeutic, FGI-106, which displays potent and broad-spectrum inhibition of lethal viral hemorrhagic fevers pathogens, including Ebola, Rift Valley and Dengue Fever viruses, in cell-based assays. Using mouse models of Ebola virus, we further demonstrate that FGI-106 can protect animals from an otherwise lethal infection when used either in a prophylactic or therapeutic setting. A single treatment, administered 1 day after infection, is sufficient to protect animals from lethal Ebola virus challenge. Cell-based assays also identified inhibitory activity against divergent virus families, which supports a hypothesis that FGI-106 interferes with a common pathway utilized by different viruses. These findings suggest FGI-106 may provide an opportunity for targeting viral diseases.

  2. Factors influencing success of clinical genome sequencing across a broad spectrum of disorders

    Science.gov (United States)

    Lise, Stefano; Broxholme, John; Cazier, Jean-Baptiste; Rimmer, Andy; Kanapin, Alexander; Lunter, Gerton; Fiddy, Simon; Allan, Chris; Aricescu, A. Radu; Attar, Moustafa; Babbs, Christian; Becq, Jennifer; Beeson, David; Bento, Celeste; Bignell, Patricia; Blair, Edward; Buckle, Veronica J; Bull, Katherine; Cais, Ondrej; Cario, Holger; Chapel, Helen; Copley, Richard R; Cornall, Richard; Craft, Jude; Dahan, Karin; Davenport, Emma E; Dendrou, Calliope; Devuyst, Olivier; Fenwick, Aimée L; Flint, Jonathan; Fugger, Lars; Gilbert, Rodney D; Goriely, Anne; Green, Angie; Greger, Ingo H.; Grocock, Russell; Gruszczyk, Anja V; Hastings, Robert; Hatton, Edouard; Higgs, Doug; Hill, Adrian; Holmes, Chris; Howard, Malcolm; Hughes, Linda; Humburg, Peter; Johnson, David; Karpe, Fredrik; Kingsbury, Zoya; Kini, Usha; Knight, Julian C; Krohn, Jonathan; Lamble, Sarah; Langman, Craig; Lonie, Lorne; Luck, Joshua; McCarthy, Davis; McGowan, Simon J; McMullin, Mary Frances; Miller, Kerry A; Murray, Lisa; Németh, Andrea H; Nesbit, M Andrew; Nutt, David; Ormondroyd, Elizabeth; Oturai, Annette Bang; Pagnamenta, Alistair; Patel, Smita Y; Percy, Melanie; Petousi, Nayia; Piazza, Paolo; Piret, Sian E; Polanco-Echeverry, Guadalupe; Popitsch, Niko; Powrie, Fiona; Pugh, Chris; Quek, Lynn; Robbins, Peter A; Robson, Kathryn; Russo, Alexandra; Sahgal, Natasha; van Schouwenburg, Pauline A; Schuh, Anna; Silverman, Earl; Simmons, Alison; Sørensen, Per Soelberg; Sweeney, Elizabeth; Taylor, John; Thakker, Rajesh V; Tomlinson, Ian; Trebes, Amy; Twigg, Stephen RF; Uhlig, Holm H; Vyas, Paresh; Vyse, Tim; Wall, Steven A; Watkins, Hugh; Whyte, Michael P; Witty, Lorna; Wright, Ben; Yau, Chris; Buck, David; Humphray, Sean; Ratcliffe, Peter J; Bell, John I; Wilkie, Andrew OM; Bentley, David; Donnelly, Peter; McVean, Gilean

    2015-01-01

    To assess factors influencing the success of whole genome sequencing for mainstream clinical diagnosis, we sequenced 217 individuals from 156 independent cases across a broad spectrum of disorders in whom prior screening had identified no pathogenic variants. We quantified the number of candidate variants identified using different strategies for variant calling, filtering, annotation and prioritisation. We found that jointly calling variants across samples, filtering against both local and external databases, deploying multiple annotation tools and using familial transmission above biological plausibility contributed to accuracy. Overall, we identified disease causing variants in 21% of cases, rising to 34% (23/68) for Mendelian disorders and 57% (8/14) in trios. We also discovered 32 potentially clinically actionable variants in 18 genes unrelated to the referral disorder, though only four were ultimately considered reportable. Our results demonstrate the value of genome sequencing for routine clinical diagnosis, but also highlight many outstanding challenges. PMID:25985138

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

    Science.gov (United States)

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

    2017-07-01

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

  4. Isolation of a new broad spectrum antifungal polyene from Streptomyces sp. MTCC 5680.

    Science.gov (United States)

    Vartak, A; Mutalik, V; Parab, R R; Shanbhag, P; Bhave, S; Mishra, P D; Mahajan, G B

    2014-06-01

    A new polyene macrolide antibiotic PN00053 was isolated from the fermentation broth of Streptomyces sp. wild-type strain MTCC-5680. The producer strain was isolated from fertile mountain soil of Naldehra region, Himachal Pradesh, India. The compound PN00053 was purified through various steps of chromatographic techniques and bio-activity guided fractionation followed by its characterization using physiochemical properties, spectral data ((1) H-NMR, (13) C-NMR, HMBC, HSQC, and COSY) and MS analysis. PN00053 exhibited broad spectrum in vitro antifungal activity against strains of Aspergillus fumigatus (HMR), A. fumigatus ATCC 16424, Candida albicans (I.V.), C. albicans ATCC 14503, C. krusei GO6, C. glabrata HO4, Cryptococcus neoformans, Trichophyton sp. as well as fluconazole resistant strains C. krusei GO3 and C. glabrata HO5. It did not inhibit growth of gram positive and gram-negative bacteria, displaying its specificity against fungi. PN00053 is a novel polyene macrolide isolated from a wild strain of Streptomyces sp. PM0727240 (MTCC5680), an isolate from the mountainous rocky regions of Himachal Pradesh, India. The compound is a new derivative of the antibiotic Roflamycoin [32, 33-didehydroroflamycoin (DDHR)]. It displayed broad spectrum antifungal activity against yeast and filamentous fungi. However, it did not show any antibacterial activity. The in vitro study revealed that PN00053 has better potency as compared to clinical gold standard fluconazole. The development of pathogenic resistance against the polyenes has been seldom reported. Hence, we envisage PN00053 could be a potential antifungal lead. © 2014 The Society for Applied Microbiology.

  5. Antimicrobial Activity of Chlorhexidine, Peracetic acid/ Peroxide hydrogen and Alcohol based compound on Isolated Bacteria in Madani Heart Hospital, Tabriz, Azerbaijan, Iran

    Directory of Open Access Journals (Sweden)

    Reza Ghotaslou

    2012-06-01

    Full Text Available Purpose: The aim of present study was to investigate the effect of chemical agents on the clinical isolates in Madani Heart Hospital, Tabriz, Iran. Methods: The minimum bactericide concentration (MBC of disinfectants including chlorhexidine (Fort, peracetic acid (Micro and an alcohol based compound (Deconex on selected bacteria at various dilutions were determined by the standard suspension technique. Results: MBC of Micro, Fort and Deconex were 2-128 mg/L, 2-64 mg/L and 4 - 32 mg/L, respectively. The Gram negative bacteria were more resistance to disinfectant relation to Gram positive bacteria. Conclusion: The results showed that these agents are able to eradicate the bacteria and they can be used lonely.

  6. Antimicrobial Activity of Chlorhexidine, Peracetic acid/ Peroxide hydrogen and Alcohol based compound on Isolated Bacteria in Madani Heart Hospital, Tabriz, Azerbaijan, Iran

    Science.gov (United States)

    Ghotaslou, Reza; Bahrami, Nashmil

    2012-01-01

    Purpose: The aim of present study was to investigate the effect of chemical agents on the clinical isolates in Madani Heart Hospital, Tabriz, Iran. Methods: The minimum bactericide concentration (MBC) of disinfectants including chlorhexidine (Fort), peracetic acid (Micro) and an alcohol based compound (Deconex) on selected bacteria at various dilutions were determined by the standard suspension technique. Results: MBC of Micro, Fort and Deconex were 2-128 mg/L, 2-64 mg/L and 4 - 32 mg/L, respectively. The Gram negative bacteria were more resistance to disinfectant relation to Gram positive bacteria. Conclusion: The results showed that these agents are able to eradicate the bacteria and they can be used lonely. PMID:24312771

  7. Trends in broad-spectrum antibiotic prescribing for children with acute otitis media in the United States, 1998–2004

    Directory of Open Access Journals (Sweden)

    Gambler Angela S

    2009-06-01

    Full Text Available Abstract Background Overuse of broad-spectrum antibiotics is associated with antibiotic resistance. Acute otitis media (AOM is responsible for a large proportion of antibiotics prescribed for US children. Rates of broad-spectrum antibiotic prescribing for AOM are unknown. Methods Analysis of the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey, 1998 to 2004 (N = 6,878. Setting is office-based physicians, hospital outpatient departments, and emergency departments. Patients are children aged 12 years and younger prescribed antibiotics for acute otitis media. Main outcome measure is percentage of broad-spectrum antibiotics, defined as amoxicillin/clavulanate, macrolides, cephalosporins and quinolones. Results Broad-spectrum prescribing for acute otitis media increased from 34% of visits in 1998 to 45% of visits in 2004 (P Conclusion Prescribing of broad-spectrum antibiotics for acute otitis media has steadily increased from 1998 to 2004. Associations with non-clinical factors suggest potential for improvement in prescribing practice.

  8. Designing a broad-spectrum integrative approach for cancer prevention and treatment.

    Science.gov (United States)

    Block, Keith I; Gyllenhaal, Charlotte; Lowe, Leroy; Amedei, Amedeo; Amin, A R M Ruhul; Amin, Amr; Aquilano, Katia; Arbiser, Jack; Arreola, Alexandra; Arzumanyan, Alla; Ashraf, S Salman; Azmi, Asfar S; Benencia, Fabian; Bhakta, Dipita; Bilsland, Alan; Bishayee, Anupam; Blain, Stacy W; Block, Penny B; Boosani, Chandra S; Carey, Thomas E; Carnero, Amancio; Carotenuto, Marianeve; Casey, Stephanie C; Chakrabarti, Mrinmay; Chaturvedi, Rupesh; Chen, Georgia Zhuo; Chen, Helen; Chen, Sophie; Chen, Yi Charlie; Choi, Beom K; Ciriolo, Maria Rosa; Coley, Helen M; Collins, Andrew R; Connell, Marisa; Crawford, Sarah; Curran, Colleen S; Dabrosin, Charlotta; Damia, Giovanna; Dasgupta, Santanu; DeBerardinis, Ralph J; Decker, William K; Dhawan, Punita; Diehl, Anna Mae E; Dong, Jin-Tang; Dou, Q Ping; Drew, Janice E; Elkord, Eyad; El-Rayes, Bassel; Feitelson, Mark A; Felsher, Dean W; Ferguson, Lynnette R; Fimognari, Carmela; Firestone, Gary L; Frezza, Christian; Fujii, Hiromasa; Fuster, Mark M; Generali, Daniele; Georgakilas, Alexandros G; Gieseler, Frank; Gilbertson, Michael; Green, Michelle F; Grue, Brendan; Guha, Gunjan; Halicka, Dorota; Helferich, William G; Heneberg, Petr; Hentosh, Patricia; Hirschey, Matthew D; Hofseth, Lorne J; Holcombe, Randall F; Honoki, Kanya; Hsu, Hsue-Yin; Huang, Gloria S; Jensen, Lasse D; Jiang, Wen G; Jones, Lee W; Karpowicz, Phillip A; Keith, W Nicol; Kerkar, Sid P; Khan, Gazala N; Khatami, Mahin; Ko, Young H; Kucuk, Omer; Kulathinal, Rob J; Kumar, Nagi B; Kwon, Byoung S; Le, Anne; Lea, Michael A; Lee, Ho-Young; Lichtor, Terry; Lin, Liang-Tzung; Locasale, Jason W; Lokeshwar, Bal L; Longo, Valter D; Lyssiotis, Costas A; MacKenzie, Karen L; Malhotra, Meenakshi; Marino, Maria; Martinez-Chantar, Maria L; Matheu, Ander; Maxwell, Christopher; McDonnell, Eoin; Meeker, Alan K; Mehrmohamadi, Mahya; Mehta, Kapil; Michelotti, Gregory A; Mohammad, Ramzi M; Mohammed, Sulma I; Morre, D James; Muralidhar, Vinayak; Muqbil, Irfana; Murphy, Michael P; Nagaraju, Ganji Purnachandra; Nahta, Rita; Niccolai, Elena; Nowsheen, Somaira; Panis, Carolina; Pantano, Francesco; Parslow, Virginia R; Pawelec, Graham; Pedersen, Peter L; Poore, Brad; Poudyal, Deepak; Prakash, Satya; Prince, Mark; Raffaghello, Lizzia; Rathmell, Jeffrey C; Rathmell, W Kimryn; Ray, Swapan K; Reichrath, Jörg; Rezazadeh, Sarallah; Ribatti, Domenico; Ricciardiello, Luigi; Robey, R Brooks; Rodier, Francis; Rupasinghe, H P Vasantha; Russo, Gian Luigi; Ryan, Elizabeth P; Samadi, Abbas K; Sanchez-Garcia, Isidro; Sanders, Andrew J; Santini, Daniele; Sarkar, Malancha; Sasada, Tetsuro; Saxena, Neeraj K; Shackelford, Rodney E; Shantha Kumara, H M C; Sharma, Dipali; Shin, Dong M; Sidransky, David; Siegelin, Markus David; Signori, Emanuela; Singh, Neetu; Sivanand, Sharanya; Sliva, Daniel; Smythe, Carl; Spagnuolo, Carmela; Stafforini, Diana M; Stagg, John; Subbarayan, Pochi R; Sundin, Tabetha; Talib, Wamidh H; Thompson, Sarah K; Tran, Phuoc T; Ungefroren, Hendrik; Vander Heiden, Matthew G; Venkateswaran, Vasundara; Vinay, Dass S; Vlachostergios, Panagiotis J; Wang, Zongwei; Wellen, Kathryn E; Whelan, Richard L; Yang, Eddy S; Yang, Huanjie; Yang, Xujuan; Yaswen, Paul; Yedjou, Clement; Yin, Xin; Zhu, Jiyue; Zollo, Massimo

    2015-12-01

    Targeted therapies and the consequent adoption of "personalized" oncology have achieved notable successes in some cancers; however, significant problems remain with this approach. Many targeted therapies are highly toxic, costs are extremely high, and most patients experience relapse after a few disease-free months. Relapses arise from genetic heterogeneity in tumors, which harbor therapy-resistant immortalized cells that have adopted alternate and compensatory pathways (i.e., pathways that are not reliant upon the same mechanisms as those which have been targeted). To address these limitations, an international task force of 180 scientists was assembled to explore the concept of a low-toxicity "broad-spectrum" therapeutic approach that could simultaneously target many key pathways and mechanisms. Using cancer hallmark phenotypes and the tumor microenvironment to account for the various aspects of relevant cancer biology, interdisciplinary teams reviewed each hallmark area and nominated a wide range of high-priority targets (74 in total) that could be modified to improve patient outcomes. For these targets, corresponding low-toxicity therapeutic approaches were then suggested, many of which were phytochemicals. Proposed actions on each target and all of the approaches were further reviewed for known effects on other hallmark areas and the tumor microenvironment. Potential contrary or procarcinogenic effects were found for 3.9% of the relationships between targets and hallmarks, and mixed evidence of complementary and contrary relationships was found for 7.1%. Approximately 67% of the relationships revealed potentially complementary effects, and the remainder had no known relationship. Among the approaches, 1.1% had contrary, 2.8% had mixed and 62.1% had complementary relationships. These results suggest that a broad-spectrum approach should be feasible from a safety standpoint. This novel approach has potential to be relatively inexpensive, it should help us

  9. The effects of exogenous catalase on broad-spectrum near-UV (300-400nm) treated Escherichia coli cells

    International Nuclear Information System (INIS)

    Sammartano, L.J.; Tuveson, R.W.

    1984-01-01

    Catalase incorporated into plating medium protects against inactivation and mutagenesis by broad-spectrum near-ultraviolet wavelength (300-400nm) (NUV) radiation in strains of Escherichia coli. Plating medium containing catalase does not provide protection against inactivation by wavelengths in the FUV region. Catalase added to the cell suspension during or added immediately after NUV exposure also protects against inactivation. The protection provided by catalase suggests a possible role for hydrogen peroxide in the processes of inactivation and mutagenesis by broad-spectrum NUV. (author)

  10. Dissecting disease entities out of the broad spectrum of bipolar-disorders.

    Science.gov (United States)

    Levine, Joseph; Toker, Lilach; Agam, Galila

    2018-01-01

    The etiopathology of bipolar disorders is yet unraveled and new avenues should be pursued. One such avenue may be based on the assumption that the bipolar broad spectrum includes, among others, an array of rare medical disease entities. Towards this aim we propose a dissecting approach based on a search for rare medical diseases with known etiopathology which also exhibit bipolar disorders symptomatology. We further suggest that the etiopathologic mechanisms underlying such rare medical diseases may also underlie a rare variant of bipolar disorder. Such an assumption may be further reinforced if both the rare medical disease and its bipolar clinical phenotype demonstrate a] a similar mode of inheritance (i.e, autosomal dominant); b] brain involvement; and c] data implicating that the etiopathological mechanisms underlying the rare diseases affect biological processes reported to be associated with bipolar disorders and their treatment. We exemplify our suggested approach by a rare case of autosomal dominant leucodystrophy, a disease entity exhibiting nuclear lamin B1 pathology also presenting bipolar symptomatology. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. XA23 is an executor R protein and confers broad-spectrum disease resistance in rice.

    Science.gov (United States)

    Wang, Chunlian; Zhang, Xiaoping; Fan, Yinglun; Gao, Ying; Zhu, Qinlong; Zheng, Chongke; Qin, Tengfei; Li, Yanqiang; Che, Jinying; Zhang, Mingwei; Yang, Bing; Liu, Yaoguang; Zhao, Kaijun

    2014-11-09

    The majority of plant disease resistance (R) genes encode proteins that share common structural features. However, the transcription activator-like effector (TALE) associated executor type R genes show no considerable sequence homology to any known R genes. We adopted a map-based cloning approach and TALE-based technology to isolate and characterize Xa23, a new executor R gene derived from the wild rice (Oryza rufipogon) that confers an extremely broad spectrum of resistance to bacterial blight caused by Xanthomonas oryzae pv. oryzae (Xoo). Xa23 encodes a 113-amino acid protein that shares 50% identity to the known executor R protein XA10. The predicted transmembrane helices in XA23 also overlap with those of XA10. Unlike Xa10, however, Xa23 transcription is specifically activated by AvrXa23, a TALE present in all examined Xoo field isolates. Moreover, the susceptible xa23 allele has an identical open reading frame of Xa23, but differs in promoter region by lacking the TALE binding-element (EBE) for AvrXa23. XA23 can trigger strong hypersensitive response in rice, tobacco and tomato. Our results provide the first evidence that plant genomes have an executor R gene family in which members execute their function and spectrum of disease resistance by recognizing the cognate TALEs in pathogen. © The Author 2014. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPB and IPPE, SIBS, CAS.

  12. Arbidol: a broad-spectrum antiviral that inhibits acute and chronic HCV infection

    Directory of Open Access Journals (Sweden)

    Pécheur Eve-Isabelle

    2006-07-01

    Full Text Available Abstract Arbidol (ARB is an antiviral compound that was originally proven effective for treatment of influenza and several other respiratory viral infections. The broad spectrum of ARB anti-viral activity led us to evaluate its effect on hepatitis C virus (HCV infection and replication in cell culture. Long-term ARB treatment of Huh7 cells chronically replicating a genomic length genotype 1b replicon resulted in sustained reduction of viral RNA and protein expression, and eventually cured HCV infected cells. Pre-treatment of human hepatoma Huh7.5.1 cells with 15 μM ARB for 24 to 48 hours inhibited acute infection with JFH-1 virus by up to 1000-fold. The inhibitory effect of ARB on HCV was not due to generalized cytotoxicity, nor to augmentation of IFN antiviral signaling pathways, but involved impaired virus-mediated membrane fusion. ARB's affinity for membranes may inhibit several aspects of the HCV lifecycle that are membrane-dependent.

  13. Ceftiofur sodium, a broad-spectrum cephalosporin: evaluation in vitro and in vivo in mice.

    Science.gov (United States)

    Yancey, R J; Kinney, M L; Roberts, B J; Goodenough, K R; Hamel, J C; Ford, C W

    1987-07-01

    Ceftiofur sodium, a broad-spectrum beta-lactamase-resistant cephalosporin, was evaluated in vitro and in vivo in mice. Ceftiofur is the sodium salt of (6R, 7R)-7[( 2-amino-4-thiazolyl)-Z- (methoxyimino)acetyl]amino)-3-[( (2-furanylcarbonyl)thio]methyl)-8-oxo-5- thia-1-azabicyclo-[4.2.0]oct-2-ene-2-carboxylate. Minimal inhibitory concentration values were obtained with 264 strains representing 9 genera and 17 species of bacterial pathogens from cattle, swine, sheep, horses, poultry, dogs, cats, and human beings. Ceftiofur was more active than was ampicillin against all strains tested including beta-lactamase-producing organisms. In mice with systemic infections, ceftiofur was more active than or equivalent to ampicillin, cephalothin, cefamandole, cloxacillin, cefoperazone, or pirlimycin. These protection tests included infections with Escherichia coli, Haemophilus pleuropneumoniae, H somnus, Pasteurella haemolytica, P multocida, Salmonella typhimurium, or Staphylococcus aureus. In infant mice with E coli-induced lethal diarrhea and in mice with S aureus and E coli-induced mastitis, ceftiofur was comparable or more active than was ampicillin.

  14. Broad-spectrum non-toxic antiviral nanoparticles with a virucidal inhibition mechanism

    Science.gov (United States)

    Cagno, Valeria; Andreozzi, Patrizia; D'Alicarnasso, Marco; Jacob Silva, Paulo; Mueller, Marie; Galloux, Marie; Le Goffic, Ronan; Jones, Samuel T.; Vallino, Marta; Hodek, Jan; Weber, Jan; Sen, Soumyo; Janeček, Emma-Rose; Bekdemir, Ahmet; Sanavio, Barbara; Martinelli, Chiara; Donalisio, Manuela; Rameix Welti, Marie-Anne; Eleouet, Jean-Francois; Han, Yanxiao; Kaiser, Laurent; Vukovic, Lela; Tapparel, Caroline; Král, Petr; Krol, Silke; Lembo, David; Stellacci, Francesco

    2018-02-01

    Viral infections kill millions yearly. Available antiviral drugs are virus-specific and active against a limited panel of human pathogens. There are broad-spectrum substances that prevent the first step of virus-cell interaction by mimicking heparan sulfate proteoglycans (HSPG), the highly conserved target of viral attachment ligands (VALs). The reversible binding mechanism prevents their use as a drug, because, upon dilution, the inhibition is lost. Known VALs are made of closely packed repeating units, but the aforementioned substances are able to bind only a few of them. We designed antiviral nanoparticles with long and flexible linkers mimicking HSPG, allowing for effective viral association with a binding that we simulate to be strong and multivalent to the VAL repeating units, generating forces (~190 pN) that eventually lead to irreversible viral deformation. Virucidal assays, electron microscopy images, and molecular dynamics simulations support the proposed mechanism. These particles show no cytotoxicity, and in vitro nanomolar irreversible activity against herpes simplex virus (HSV), human papilloma virus, respiratory syncytial virus (RSV), dengue and lenti virus. They are active ex vivo in human cervicovaginal histocultures infected by HSV-2 and in vivo in mice infected with RSV.

  15. Development of broad-spectrum human monoclonal antibodies for rabies post-exposure prophylaxis

    International Nuclear Information System (INIS)

    Benedictis, P. de; Minola, A.; Rota, E.; Aiello, R.; Zecchin, B.; Salomoni, A.; Foglierini, M.; Agatic, G.; Vanzetta, F.; Lavenir, R.; Lepelletier, A.; Bentley, E.; Weiss, R.; Cattoli, G.

    2016-01-01

    Full text: Currently available rabies post-exposure prophylaxis (PEP) for use in humans includes equine or human rabies immunoglobulins (RIG). The replacement of RIG with an equally or more potent and safer product is strongly encouraged due to the high costs and limited availability of existing RIG. In this study, we identified two broadly neutralizing human monoclonal antibodies that represent a valid and affordable alternative to RIG in rabies PEP. Memory B cells from four selected vaccinated donors were immortalized and monoclonal antibodies were tested for neutralizing activity and epitope specificity. Two antibodies, identified as RVC20 and RVC58 (binding to antigenic site I and III, respectively), were selected for their potency and broad-spectrum reactivity. In vitro, RVC20 and RVC58 were able to neutralize all 35 rabies virus (RABV) and 25 non-RABV lyssaviruses. They showed higher potency and breath compared to antibodies under clinical development (namely CR57, CR4098, and RAB1) and commercially available human RIG. In vivo, the RVC20–RVC58 cocktail protected Syrian hamsters from a lethal RABV challenge and did not affect the endogenous hamster post-vaccination antibody response. (author)

  16. Broad spectrum pro-quorum-sensing molecules as inhibitors of virulence in vibrios.

    Directory of Open Access Journals (Sweden)

    Wai-Leung Ng

    Full Text Available Quorum sensing (QS is a bacterial cell-cell communication process that relies on the production and detection of extracellular signal molecules called autoinducers. QS allows bacteria to perform collective activities. Vibrio cholerae, a pathogen that causes an acute disease, uses QS to repress virulence factor production and biofilm formation. Thus, molecules that activate QS in V. cholerae have the potential to control pathogenicity in this globally important bacterium. Using a whole-cell high-throughput screen, we identified eleven molecules that activate V. cholerae QS: eight molecules are receptor agonists and three molecules are antagonists of LuxO, the central NtrC-type response regulator that controls the global V. cholerae QS cascade. The LuxO inhibitors act by an uncompetitive mechanism by binding to the pre-formed LuxO-ATP complex to inhibit ATP hydrolysis. Genetic analyses suggest that the inhibitors bind in close proximity to the Walker B motif. The inhibitors display broad-spectrum capability in activation of QS in Vibrio species that employ LuxO. To the best of our knowledge, these are the first molecules identified that inhibit the ATPase activity of a NtrC-type response regulator. Our discovery supports the idea that exploiting pro-QS molecules is a promising strategy for the development of novel anti-infectives.

  17. Development and characterization of novel chimeric monoclonal antibodies for broad spectrum neutralization of rabies virus.

    Directory of Open Access Journals (Sweden)

    Pan Kyeom Kim

    Full Text Available Current post-exposure prophylaxis for rabies virus infection has several limitations in terms of supply, cost, safety, and efficacy. Attempts to replace human or equine rabies immune globulins (HRIG or ERIG have been made by several companies and institutes. We developed potent monoclonal antibodies to neutralize a broad spectrum of rabies viruses by screening hybridomas received from the U.S. Centers for Disease Control and Prevention (CDC. Two kinds of chimeric human antibodies (chimeric #7 and #17 were constructed by cloning the variable regions from selected hybridomas and the constant region of a human antibody. Two antibodies were bound to antigenic site III and I/IV, respectively, and were able to neutralize 51 field isolates of rabies virus that were isolated at different times and places such as Asia, Africa, North America, South America, and Australia. These two antibodies neutralize rabies viruses with high efficacy in an in vivo test using Syrian hamster and mouse models and show low risk for adverse immunogenicity.

  18. Development and characterization of novel chimeric monoclonal antibodies for broad spectrum neutralization of rabies virus.

    Science.gov (United States)

    Kim, Pan Kyeom; Keum, Sun Ju; Osinubi, Modupe O V; Franka, Richard; Shin, Ji Young; Park, Sang Tae; Kim, Man Su; Park, Mi Jung; Lee, Soo Young; Carson, William; Greenberg, Lauren; Yu, Pengcheng; Tao, Xiaoyan; Lihua, Wang; Tang, Qing; Liang, Guodong; Shampur, Madhusdana; Rupprecht, Charles E; Chang, Shin Jae

    2017-01-01

    Current post-exposure prophylaxis for rabies virus infection has several limitations in terms of supply, cost, safety, and efficacy. Attempts to replace human or equine rabies immune globulins (HRIG or ERIG) have been made by several companies and institutes. We developed potent monoclonal antibodies to neutralize a broad spectrum of rabies viruses by screening hybridomas received from the U.S. Centers for Disease Control and Prevention (CDC). Two kinds of chimeric human antibodies (chimeric #7 and #17) were constructed by cloning the variable regions from selected hybridomas and the constant region of a human antibody. Two antibodies were bound to antigenic site III and I/IV, respectively, and were able to neutralize 51 field isolates of rabies virus that were isolated at different times and places such as Asia, Africa, North America, South America, and Australia. These two antibodies neutralize rabies viruses with high efficacy in an in vivo test using Syrian hamster and mouse models and show low risk for adverse immunogenicity.

  19. Development of Broad-Spectrum Halomethyl Ketone Inhibitors Against Coronavirus Main Protease 3CL(pro)

    Energy Technology Data Exchange (ETDEWEB)

    Bacha,U.; Barilla, J.; Gabelli, S.; Kiso, Y.; Amzel, L.; Freire, E.

    2008-01-01

    Coronaviruses comprise a large group of RNA viruses with diverse host specificity. The emergence of highly pathogenic strains like the SARS coronavirus (SARS-CoV), and the discovery of two new coronaviruses, NL-63 and HKU1, corroborates the high rate of mutation and recombination that have enabled them to cross species barriers and infect novel hosts. For that reason, the development of broad-spectrum antivirals that are effective against several members of this family is highly desirable. This goal can be accomplished by designing inhibitors against a target, such as the main protease 3CLpro (Mpro), which is highly conserved among all coronaviruses. Here 3CLpro derived from the SARS-CoV was used as the primary target to identify a new class of inhibitors containing a halomethyl ketone warhead. The compounds are highly potent against SARS 3CLpro with Ki's as low as 300 nm. The crystal structure of the complex of one of the compounds with 3CLpro indicates that this inhibitor forms a thioether linkage between the halomethyl carbon of the warhead and the catalytic Cys 145. Furthermore, Structure Activity Relationship (SAR) studies of these compounds have led to the identification of a pharmacophore that accurately defines the essential molecular features required for the high affinity.

  20. Insight into the mechanism of action of temporin-SHa, a new broad-spectrum antiparasitic and antibacterial agent.

    Directory of Open Access Journals (Sweden)

    Zahid Raja

    Full Text Available Antimicrobial peptides (AMPs are promising drugs to kill resistant pathogens. In contrast to bacteria, protozoan parasites, such as Leishmania, were little studied. Therefore, the antiparasitic mechanism of AMPs is still unclear. In this study, we sought to get further insight into this mechanism by focusing our attention on temporin-SHa (SHa, a small broad-spectrum AMP previously shown to be active against Leishmania infantum. To improve activity, we designed analogs of SHa and compared the antibacterial and antiparasitic mechanisms. [K3]SHa emerged as a highly potent compound active against a wide range of bacteria, yeasts/fungi, and trypanosomatids (Leishmania and Trypanosoma, with leishmanicidal intramacrophagic activity and efficiency toward antibiotic-resistant strains of S. aureus and antimony-resistant L. infantum. Multipassage resistance selection demonstrated that temporins-SH, particularly [K3]SHa, are not prone to induce resistance in Escherichia coli. Analysis of the mode of action revealed that bacterial and parasite killing occur through a similar membranolytic mechanism involving rapid membrane permeabilization and depolarization. This was confirmed by high-resolution imaging (atomic force microscopy and field emission gun-scanning electron microscopy. Multiple combined techniques (nuclear magnetic resonance, surface plasmon resonance, differential scanning calorimetry allowed us to detail peptide-membrane interactions. [K3]SHa was shown to interact selectively with anionic model membranes with a 4-fold higher affinity (KD = 3 x 10-8 M than SHa. The amphipathic α-helical peptide inserts in-plane in the hydrophobic lipid bilayer and disrupts the acyl chain packing via a detergent-like effect. Interestingly, cellular events, such as mitochondrial membrane depolarization or DNA fragmentation, were observed in L. infantum promastigotes after exposure to SHa and [K3]SHa at concentrations above IC50. Our results indicate that these

  1. Wild Coastline Birds as Reservoirs of Broad-Spectrum-β-Lactamase-Producing Enterobacteriaceae in Miami Beach, Florida

    Science.gov (United States)

    Potron, Anaïs; De La Cuesta, Carolina; Cleary, Timothy; Nordmann, Patrice; Munoz-Price, L. Silvia

    2012-01-01

    A high rate of broad-spectrum-β-lactamase-producing Escherichia coli isolates was identified from seagull and pelican feces collected in the Miami Beach, Florida, area. The most commonly identified resistance determinants were CMY-2 and CTX-M-15. Those wild birds might be therefore considered vehicles for wide dissemination of multidrug-resistant Enterobacteriaceae in the United States. PMID:22314536

  2. Broad-Spectrum Inhibitors against 3C-Like Proteases of Feline Coronaviruses and Feline Caliciviruses

    Science.gov (United States)

    Shivanna, Vinay; Narayanan, Sanjeev; Prior, Allan M.; Weerasekara, Sahani; Hua, Duy H.; Kankanamalage, Anushka C. Galasiti; Groutas, William C.; Chang, Kyeong-Ok

    2015-01-01

    ABSTRACT Feline infectious peritonitis and virulent, systemic calicivirus infection are caused by certain types of feline coronaviruses (FCoVs) and feline caliciviruses (FCVs), respectively, and are important infectious diseases with high fatality rates in members of the Felidae family. While FCoV and FCV belong to two distinct virus families, the Coronaviridae and the Caliciviridae, respectively, they share a dependence on viral 3C-like protease (3CLpro) for their replication. Since 3CLpro is functionally and structurally conserved among these viruses and essential for viral replication, 3CLpro is considered a potential target for the design of antiviral drugs with broad-spectrum activities against these distinct and highly important viral infections. However, small-molecule inhibitors against the 3CLpro enzymes of FCoV and FCV have not been previously identified. In this study, derivatives of peptidyl compounds targeting 3CLpro were synthesized and evaluated for their activities against FCoV and FCV. The structures of compounds that showed potent dual antiviral activities with a wide margin of safety were identified and are discussed. Furthermore, the in vivo efficacy of 3CLpro inhibitors was evaluated using a mouse model of coronavirus infection. Intraperitoneal administration of two 3CLpro inhibitors in mice infected with murine hepatitis virus A59, a hepatotropic coronavirus, resulted in significant reductions in virus titers and pathological lesions in the liver compared to the findings for the controls. These results suggest that the series of 3CLpro inhibitors described here may have the potential to be further developed as therapeutic agents against these important viruses in domestic and wild cats. This study provides important insights into the structure and function relationships of 3CLpro for the design of antiviral drugs with broader antiviral activities. IMPORTANCE Feline infectious peritonitis virus (FIPV) is the leading cause of death in young cats

  3. Overexpression of NPR1 in Brassica juncea Confers Broad Spectrum Resistance to Fungal Pathogens

    Directory of Open Access Journals (Sweden)

    Sajad Ali

    2017-10-01

    Full Text Available Brassica juncea (Indian mustard is a commercially important oil seed crop, which is highly affected by many biotic stresses. Among them, Alternaria leaf blight and powdery mildew are the most devastating diseases leading to huge yield losses in B. juncea around the world. In this regard, genetic engineering is a promising tool that may possibly allow us to enhance the B. juncea disease resistance against these pathogens. NPR1 (non-expressor of pathogen-related gene 1 is a bonafide receptor of salicylic acid (SA which modulates multiple immune responses in plants especially activation of induced and systemic acquired resistance (SAR. Here, we report the isolation and characterization of new NPR1 homolog (BjNPR1 from B. juncea. The phylogenetic tree constructed based on the deduced sequence of BjNPR1 with homologs from other species revealed that BjNPR1 grouped together with other known NPR1 proteins of Cruciferae family, and was nearest to B. napus. Furthermore, expression analysis showed that BjNPR1 was upregulated after SA treatment and fungal infection but not by jasmonic acid or abscisic acid. To understand the defensive role of this gene, we generated B. juncea transgenic lines overexpressing BjNPR1, and further confirmed by PCR and Southern blotting. The transgenic lines showed no phenotypic abnormalities, and constitutive expression of BjNPR1 activates defense signaling pathways by priming the expression of antifungal PR genes. Moreover, BjNPR1 transgenic lines showed enhanced resistance to Alternaria brassicae and Erysiphe cruciferarum as there was delay in symptoms and reduced disease severity than non-transgenic plants. In addition, the rate of disease spreading to uninfected or distal parts was also delayed in transgenic plants thus suggesting the activation of SAR. Altogether, the present study suggests that BjNPR1 is involved in broad spectrum of disease resistance against fungal pathogens.

  4. A Broad-Spectrum Integrative Design for Cancer Prevention and Therapy

    Science.gov (United States)

    Block, Keith I.; Gyllenhaal, Charlotte; Lowe, Leroy; Amedei, Amedeo; Amin, A.R.M. Ruhul; Amin, Amr; Aquilano, Katia; Arbiser, Jack; Arreola, Alexandra; Arzumanyan, Alla; Ashraf, S. Salman; Azmi, Asfar S.; Benencia, Fabian; Bhakta, Dipita; Bilsland, Alan; Bishayee, Anupam; Blain, Stacy W.; Block, Penny B.; Boosani, Chandra S.; Carey, Thomas E.; Carnero, Amancio; Carotenuto, Marianeve; Casey, Stephanie C.; Chakrabarti, Mrinmay; Chaturvedi, Rupesh; Chen, Georgia Zhuo; Chen, Helen; Chen, Sophie; Chen, Yi Charlie; Choi, Beom K.; Ciriolo, Maria Rosa; Coley, Helen M.; Collins, Andrew R.; Connell, Marisa; Crawford, Sarah; Curran, Colleen S.; Dabrosin, Charlotta; Damia, Giovanna; Dasgupta, Santanu; DeBerardinis, Ralph J.; Decker, William K.; Dhawan, Punita; Diehl, Anna Mae E.; Dong, Jin-Tang; Dou, Q. Ping; Drew, Janice E.; Elkord, Eyad; El-Rayes, Bassel; Feitelson, Mark A.; Felsher, Dean W.; Ferguson, Lynnette R; Fimognari, Carmela; Firestone, Gary L.; Frezza, Christian; Fujii, Hiromasa; Fuster, Mark M.; Generali, Daniele; Georgakilas, Alexandros G.; Gieseler, Frank; Gilbertson, Michael; Green, Michelle F.; Grue, Brendan; Guha, Gunjan; Halicka, Dorota; Helferich, William G.; Heneberg, Petr; Hentosh, Patricia; Hirschey, Matthew D.; Hofseth, Lorne J.; Holcombe, Randall F.; Honoki, Kanya; Hsu, Hsue-Yin; Huang, Gloria S.; Jensen, Lasse D.; Jiang, Wen G.; Jones, Lee W.; Karpowicz, Phillip A.; Keith, W Nicol; Kerkar, Sid P.; Khan, Gazala N.; Khatami, Mahin; Ko, Young H.; Kucuk, Omer; Kulathinal, Rob J.; Kumar, Nagi B.; Kumara, H.M.C. Shantha; Kwon, Byoung S.; Le, Anne; Lea, Michael A.; Lee, Ho-Young; Lichtor, Terry; Lin, Liang-Tzung; Locasale, Jason W.; Lokeshwar, Bal L.; Longo, Valter D.; Lyssiotis, Costas A.; MacKenzie, Karen L.; Malhotra, Meenakshi; Marino, Maria; Martinez-Chantar, Maria L.; Matheu, Ander; Maxwell, Christopher; McDonnell, Eoin; Meeker, Alan K.; Mehrmohamadi, Mahya; Mehta, Kapil; Michelotti, Gregory A.; Mohammad, Ramzi M.; Mohammed, Sulma I.; Morre, D. James; Muqbil, Irfana; Muralidhar, Vinayak; Murphy, Michael P.; Nagaraju, Ganji Purnachandra; Nahta, Rita; Niccolai, Elena; Nowsheen, Somaira; Panis, Carolina; Pantano, Francesco; Parslow, Virginia R.; Pawelec, Graham; Pedersen, Peter L.; Poore, Brad; Poudyal, Deepak; Prakash, Satya; Prince, Mark; Raffaghello, Lizzia; Rathmell, Jeffrey C.; Rathmell, W. Kimryn; Ray, Swapan K.; Reichrath, Jörg; Rezazadeh, Sarallah; Ribatti, Domenico; Ricciardiello, Luigi; Robey, R. Brooks; Rodier, Francis; Rupasinghe, H.P. Vasantha; Russo, Gian Luigi; Ryan, Elizabeth P.; Samadi, Abbas K.; Sanchez-Garcia, Isidro; Sanders, Andrew J.; Santini, Daniele; Sarkar, Malancha; Sasada, Tetsuro; Saxena, Neeraj K.; Shackelford, Rodney E; Sharma, Dipali; Shin, Dong M.; Sidransky, David; Siegelin, Markus David; Signori, Emanuela; Singh, Neetu; Sivanand, Sharanya; Sliva, Daniel; Smythe, Carl; Spagnuolo, Carmela; Stafforini, Diana M.; Stagg, John; Subbarayan, Pochi R.; Sundin, Tabetha; Talib, Wamidh H.; Thompson, Sarah K.; Tran, Phuoc T.; Ungefroren, Hendrik; Vander Heiden, Matthew G.; Venkateswaran, Vasundara; Vinay, Dass S.; Vlachostergios, Panagiotis J.; Wang, Zongwei; Wellen, Kathryn E.; Whelan, Richard L.; Yang, Eddy S.; Yang, Huanjie; Yang, Xujuan; Yaswen, Paul; Yedjou, Clement; Yin, Xin; Zhu, Jiyue; Zollo, Massimo

    2016-01-01

    Targeted therapies and the consequent adoption of “personalized” oncology have achieved notable successes in some cancers; however, significant problems remain with this approach. Many targeted therapies are highly toxic, costs are extremely high, and most patients experience relapse after a few disease-free months. Relapses arise from genetic heterogeneity in tumors, which harbor therapy-resistant immortalized cells that have adopted alternate and compensatory pathways (i.e., pathways that are not reliant upon the same mechanisms as those which have been targeted). To address these limitations, an international task force of 180 scientists was assembled to explore the concept of a low-toxicity “broad-spectrum” therapeutic approach that could simultaneously target many key pathways and mechanisms. Using cancer hallmark phenotypes and the tumor microenvironment to account for the various aspects of relevant cancer biology, interdisciplinary teams reviewed each hallmark area and nominated a wide range of high-priority targets (74 in total) that could be modified to improve patient outcomes. For these targets, corresponding low-toxicity therapeutic approaches were then suggested; many of which were phytochemicals. Proposed actions on each target and all of the approaches were further reviewed for known effects on other hallmark areas and the tumor microenvironment. Potential contrary or procarcinogenic effects were found for 3.9% of the relationships between targets and hallmarks, and mixed evidence of complementary and contrary relationships was found for 7.1%. Approximately 67% of the relationships revealed potentially complementary effects, and the remainder had no known relationship. Among the approaches, 1.1% had contrary, 2.8% had mixed and 62.1% had complementary relationships. These results suggest that a broad-spectrum approach should be feasible from a safety standpoint. This novel approach has potential to help us address disease relapse, which is a

  5. The use of inexpensive broad spectrum lower toxicity therapeutics in chronic lymphocytic leukemia.

    Science.gov (United States)

    Marjanovic, Goran

    2017-01-01

    The use of new and highly efficient targeted therapies for chronic lymphocytic leukemia (CLL) is costly and out of reach for many health care systems. On the other hand, in recent years, few inexpensive, broad-spectrum low-toxicity therapeutics have proven to be effective both in the preclinical and clinical settings. In early-stage CLL, the use of 2000 mg of epigallocatechin-3-gallate (EGCG) from the green tea extract twice a day was able to reduce the absolute leukocyte count. Supplementation of >2000 IU/day of Vitamin D in early low-risk CLL patients is able to delay disease progression and postpone the moment of initiation of the first treatment. The doses of both vitamin D and EGCG were shown to be safe in older patients. Vitamin D, EGCG and Curcumin, either as monotherapy or in combination, have additive and synergistic effects with conventional chemotherapy. Further observations have identified the improvement of response to rituximab-fludarabine-cyclophosphamide (R-FC) therapy with concomitant administration of statin and aspirin combination in relapsed/refractory CLL. Finally, high dose dexamethasone with 40mg/m 2 /day for 4 days, every 28 days, either alone or with monoclonal antibody, might be used as a salvage therapy or for debulking before transplantation in refractory/resistant cases. Dexamethasone therapy is followed by transient response and high rate of infections, but fluid retention and other toxicities are lower compared to high dose methylprednisolone schedules. The low cost therapeutics discussed in this review could not be a substitute for the more effective targeted therapies, but their use in every day practice might postpone the need for early implementation of new and costly medications.

  6. Use of artificial intelligence in the design of small peptide antibiotics effective against a broad spectrum of highly antibiotic-resistant superbugs.

    Science.gov (United States)

    Cherkasov, Artem; Hilpert, Kai; Jenssen, Håvard; Fjell, Christopher D; Waldbrook, Matt; Mullaly, Sarah C; Volkmer, Rudolf; Hancock, Robert E W

    2009-01-16

    Increased multiple antibiotic resistance in the face of declining antibiotic discovery is one of society's most pressing health issues. Antimicrobial peptides represent a promising new class of antibiotics. Here we ask whether it is possible to make small broad spectrum peptides employing minimal assumptions, by capitalizing on accumulating chemical biology information. Using peptide array technology, two large random 9-amino-acid peptide libraries were iteratively created using the amino acid composition of the most active peptides. The resultant data was used together with Artificial Neural Networks, a powerful machine learning technique, to create quantitative in silico models of antibiotic activity. On the basis of random testing, these models proved remarkably effective in predicting the activity of 100,000 virtual peptides. The best peptides, representing the top quartile of predicted activities, were effective against a broad array of multidrug-resistant "Superbugs" with activities that were equal to or better than four highly used conventional antibiotics, more effective than the most advanced clinical candidate antimicrobial peptide, and protective against Staphylococcus aureus infections in animal models.

  7. Susceptibility of some oral microorganisms to chlorhexidine and paramonochlorophenol

    OpenAIRE

    Amorim,Crystiane Venditi Gomes do; Aun,Carlos Eduardo; Mayer,Marcia Pinto Alves

    2004-01-01

    Since the use of antimicrobial agents is required in endodontic therapies, this study aimed at determining the minimum inhibitory concentrations (MICs) of chlorhexidine digluconate and paramonochlorophenol (PMC) against microorganisms commonly found in endodontic infections. Both agents were tested by agar dilution tests against Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Candida albicans, Prevotella intermedia, Porphyromonas gingivalis, Porphyromon...

  8. Uses of antimicrobial genes from microbial genome

    Science.gov (United States)

    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.

  9. Acute mastoiditis in children: Middle ear cultures may help in reducing use of broad spectrum antibiotics.

    Science.gov (United States)

    Garcia, Catarina; Salgueiro, Ana Bárbara; Luís, Catarina; Correia, Paula; Brito, Maria João

    2017-01-01

    Acute mastoiditis (AM) is a suppurative infection of the mastoid air cells, representing the most frequent complication of acute otitis media. AM remains an important entity in children due to its potential complications and sequelae. We aim to describe the cases of AM admitted at our department, identify risk factors potentially associated with complications and analyse the changes in clinical approach of AM over time. Case review of clinical files of children admitted with acute mastoiditis from June 1996 to May 2013 at a Lisbon metropolitan area hospital. Data was divided into two groups (prior and after May 2005) in order to evaluate changes in AM approach over the years. 135 AM episodes were included. The median age was 3.8 years and 42% children were less than 24 months of age. Symptoms at presentation included fever (69%), ear pain (56%) and otorrhea (40%). Complications occurred in 22% patients and were more common in children under 24 months (33% vs 15%, p ≤ 0.01). Leukocyte count was significantly higher in children with complications (16.7 vs 14.5 × 10 9 /μL, p ≤ 0.05) as was C-Reactive Protein value (13 vs 6.3 mg/dL, p ≤ 0.001). There was a significant association between the development of complications and C-Reactive Protein value at admission (OR 1.892; IC95%: 1.018-2.493, p ≤ 0.01). The optimal cut-off value was 7.21 mg/dL. Over time there was a significant increase in middle ear cultures obtained by tympanocentesis during surgery (2% vs 16%, p ≤ 0,01) and also a decrease in the use of broad spectrum antibiotherapy as initial treatment (52% vs 25%,p ≤ 0,001). Children under 24 months, with high leukocyte count or with high C-Reactive Protein value should be monitored closely since complications tend to be more frequent. A CRP value of 7.21 mg/dL at admission seems to be a good cut-off to monitor children for potential complications. Throughout the period analysed more cultures were performed allowing identification of

  10. Integrated DNA walking system to characterize a broad spectrum of GMOs in food/feed matrices.

    Science.gov (United States)

    Fraiture, Marie-Alice; Herman, Philippe; Lefèvre, Loic; Taverniers, Isabel; De Loose, Marc; Deforce, Dieter; Roosens, Nancy H

    2015-08-14

    In order to provide a system fully integrated with qPCR screening, usually used in GMO routine analysis, as well as being able to detect, characterize and identify a broad spectrum of GMOs in food/feed matrices, two bidirectional DNA walking methods targeting p35S or tNOS, the most common transgenic elements found in GM crops, were developed. These newly developed DNA walking methods are completing the previously implemented DNA walking method targeting the t35S pCAMBIA element. Food/feed matrices containing transgenic crops (Bt rice or MON863 maize) were analysed using the integrated DNA walking system. First, the newly developed DNA walking methods, anchored on the sequences used for the p35S or tNOS qPCR screening, were tested on Bt rice that contains these two transgenic elements. Second, the methods were assessed on a maize sample containing a low amount of the GM MON863 event, representing a more complex matrix in terms of genome size and sensitivity. Finally, to illustrate its applicability in GMO routine analysis by enforcement laboratories, the entire workflow of the integrated strategy, including qPCR screening to detect the potential presence of GMOs and the subsequent DNA walking methods to characterize and identify the detected GMOs, was applied on a GeMMA Scheme Proficiency Test matrix. Via the characterization of the transgene flanking region between the transgenic cassette and the plant genome as well as of a part of the transgenic cassette, the presence of GMOs was properly confirmed or infirmed in all tested samples. Due to their simple procedure and their short time-frame to get results, the developed DNA walking methods proposed here can be easily implemented in GMO routine analysis by the enforcement laboratories. In providing crucial information about the transgene flanking regions and/or the transgenic cassettes, this DNA walking strategy is a key molecular tool to prove the presence of GMOs in any given food/feed matrix.

  11. Computational approaches for discovery of common immunomodulators in fungal infections: towards broad-spectrum immunotherapeutic interventions.

    Science.gov (United States)

    Kidane, Yared H; Lawrence, Christopher; Murali, T M

    2013-10-07

    newly generated or expanded data sets for further elucidation of additional drug targets. Moreover, identified immunomodulators may be used to generate experimentally testable hypotheses that could help in the discovery of broad-spectrum immunotherapeutic interventions. All of our results are available at the following supplementary website: http://bioinformatics.cs.vt.edu/~murali/supplements/2013-kidane-bmc.

  12. Pharmacy sales data versus ward stock accounting for the surveillance of broad-spectrum antibiotic use in hospitals

    Science.gov (United States)

    2011-01-01

    Background Antibiotic consumption in hospitals is commonly measured using the accumulated amount of drugs delivered from the pharmacy to ward held stocks. The reliability of this method, particularly the impact of the length of the registration periods, has not been evaluated and such evaluation was aim of the study. Methods During 26 weeks, we performed a weekly ward stock count of use of broad-spectrum antibiotics - that is second- and third-generation cephalosporins, carbapenems, and quinolones - in five hospital wards and compared the data with corresponding pharmacy sales figures during the same period. Defined daily doses (DDDs) for antibiotics were used as measurement units (WHO ATC/DDD classification). Consumption figures obtained with the two methods for different registration intervals were compared by use of intraclass correlation analysis and Bland-Altman statistics. Results Broad-spectrum antibiotics accounted for a quarter to one-fifth of all systemic antibiotics (ATC group J01) used in the hospital and varied between wards, from 12.8 DDDs per 100 bed days in a urological ward to 24.5 DDDs in a pulmonary diseases ward. For the entire study period of 26 weeks, the pharmacy and ward defined daily doses figures for all broad-spectrum antibiotics differed only by 0.2%; however, for single wards deviations varied from -4.3% to 6.9%. The intraclass correlation coefficient, pharmacy versus ward data, increased from 0.78 to 0.94 for parenteral broad-spectrum antibiotics with increasing registration periods (1-4 weeks), whereas the corresponding figures for oral broad-spectrum antibiotics (ciprofloxacin) were from 0.46 to 0.74. For all broad-spectrum antibiotics and for parenteral antibiotics, limits of agreement between the two methods showed, according to Bland-Altman statistics, a deviation of ± 5% or less from average mean DDDs at 3- and 4-weeks registration intervals. Corresponding deviation for oral antibiotics was ± 21% at a 4-weeks interval

  13. Pharmacy sales data versus ward stock accounting for the surveillance of broad-spectrum antibiotic use in hospitals.

    Science.gov (United States)

    Haug, Jon B; Myhr, Randi; Reikvam, Asmund

    2011-12-13

    Antibiotic consumption in hospitals is commonly measured using the accumulated amount of drugs delivered from the pharmacy to ward held stocks. The reliability of this method, particularly the impact of the length of the registration periods, has not been evaluated and such evaluation was aim of the study. During 26 weeks, we performed a weekly ward stock count of use of broad-spectrum antibiotics--that is second- and third-generation cephalosporins, carbapenems, and quinolones--in five hospital wards and compared the data with corresponding pharmacy sales figures during the same period. Defined daily doses (DDDs) for antibiotics were used as measurement units (WHO ATC/DDD classification). Consumption figures obtained with the two methods for different registration intervals were compared by use of intraclass correlation analysis and Bland-Altman statistics. Broad-spectrum antibiotics accounted for a quarter to one-fifth of all systemic antibiotics (ATC group J01) used in the hospital and varied between wards, from 12.8 DDDs per 100 bed days in a urological ward to 24.5 DDDs in a pulmonary diseases ward. For the entire study period of 26 weeks, the pharmacy and ward defined daily doses figures for all broad-spectrum antibiotics differed only by 0.2%; however, for single wards deviations varied from -4.3% to 6.9%. The intraclass correlation coefficient, pharmacy versus ward data, increased from 0.78 to 0.94 for parenteral broad-spectrum antibiotics with increasing registration periods (1-4 weeks), whereas the corresponding figures for oral broad-spectrum antibiotics (ciprofloxacin) were from 0.46 to 0.74. For all broad-spectrum antibiotics and for parenteral antibiotics, limits of agreement between the two methods showed, according to Bland-Altman statistics, a deviation of ± 5% or less from average mean DDDs at 3- and 4-weeks registration intervals. Corresponding deviation for oral antibiotics was ± 21% at a 4-weeks interval. There is a need for caution in

  14. Anti-microbial efficacy of green tea and chlorhexidine mouth rinses against Streptococcus mutans, Lactobacilli spp. and Candida albicans in children with severe early childhood caries: A randomized clinical study

    Directory of Open Access Journals (Sweden)

    Ann Thomas

    2016-01-01

    Full Text Available Introduction: Green tea is a beverage which is consumed worldwide and is reported to have anti-cariogenic effect. So, if it was as effective as chlorhexidine (CHX mouth rinse against cariogenic microbes it could be considered a natural, economical alternative. The purpose of this study was to evaluate and compare the anti-microbial efficacy of 0.5% green tea and 0.2% CHX mouth rinses against Streptococcus Mutans, Lactobacilli spp. and Candida Albicans. Materials and Methods: 30 children aged 4-6 years with S-ECC (based ondefs score were selected. Children were divided randomly into 2 equal groups and were asked to rinse with the prescribed mouth rinse once daily for 2 weeks after breakfast under supervision. A base-line and post rinsing non-stimulated whole salivary sample (2 ml was collected and tested for the number of colony forming units. The data was statistically analyzed using SPSS v16.0 software with one-way ANOVA and Tukey′sPOSTHOC test. Results: A statistically significant fall in colony count was found with both the mouth rinses in Streptococcus Mutans (P < 0.001, P < 0.001 and lactobacilli (P < 0.001, P < 0.001 but not against Candida albicans (P = 0.264, P = 0.264. Against Streptococcus Mutans, green tea mouth rinse was found to be significantly better than CHX mouth rinse (P = 0.005. Against lactobacilli spp, CHX mouth rinse was significantly better than green tea mouth rinse (P < 0.001. Conclusion: Green tea mouth rinse can be considered safe, economical and used without much concern. However, further studies are recommended.

  15. The secreted fructose 1,6-bisphosphate aldolase as a broad spectrum vaccine candidate against pathogenic bacteria in aquaculture.

    Science.gov (United States)

    Sun, Zhongyang; Shen, Binbing; Wu, Haizhen; Zhou, Xiangyu; Wang, Qiyao; Xiao, Jingfan; Zhang, Yuanxing

    2015-10-01

    The development of aquaculture has been hampered by different aquatic pathogens that can cause edwardsiellosis, vibriosis, or other diseases. Therefore, developing a broad spectrum vaccine against different fish diseases is necessary. In this study, fructose 1,6-bisphosphate aldolase (FBA), a conserved enzyme in the glycolytic pathway, was demonstrated to be located in the non-cytoplasmic components of five aquatic pathogenic bacteria and exhibited remarkable protection and cross-protection against these pathogens in turbot and zebrafish. Further analysis revealed that sera sampled from vaccinated turbot had a high level of specific antibody and bactericidal activity against these pathogens. Meanwhile, the increased expressions of immune response-related genes associated with antigen recognition and presentation indicated that the adaptive immune response was effectively aroused. Taken together, our results suggest that FBA can be utilized as a broad-spectrum vaccine against various pathogenic bacteria of aquaculture in the future. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Broad-spectrum enhanced absorption of graphene-molybdenum disulfide photovoltaic cells in metal-mirror microcavity

    Science.gov (United States)

    Jiang-Tao, Liu; Yun-Kai, Cao; Hong, Tong; Dai-Qiang, Wang; Zhen-Hua, Wu

    2018-04-01

    The optical absorption of graphene-molybdenum disulfide photovoltaic cells (GM-PVc) in wedge-shaped metal-mirror microcavities (w-MMCs) combined with a spectrum-splitting structure was studied. Results showed that the combination of spectrum-splitting structure and w-MMC can enable the light absorption of GM-PVcs to reach about 65% in the broad spectrum. The influence of processing errors on the absorption of GM-PVcs in w-MMCs was 3-14 times lower than that of GM-PVcs in wedge photonic crystal microcavities. The light absorption of GM-PVcs reached 60% in the broad spectrum, even with the processing errors. The proposed structure is easy to implement and may have potentially important applications in the development of ultra-thin and high-efficiency solar cells and optoelectronic devices.

  17. Screening of broad spectrum natural pesticides against conserved target arginine kinase in cotton pests by molecular modeling.

    Science.gov (United States)

    Sakthivel, Seethalakshmi; Habeeb, S K M; Raman, Chandrasekar

    2018-03-12

    Cotton is an economically important crop and its production is challenged by the diversity of pests and related insecticide resistance. Identification of the conserved target across the cotton pest will help to design broad spectrum insecticide. In this study, we have identified conserved sequences by Expressed Sequence Tag profiling from three cotton pests namely Aphis gossypii, Helicoverpa armigera, and Spodoptera exigua. One target protein arginine kinase having a key role in insect physiology and energy metabolism was studied further using homology modeling, virtual screening, molecular docking, and molecular dynamics simulation to identify potential biopesticide compounds from the Zinc natural database. We have identified four compounds having excellent inhibitor potential against the identified broad spectrum target which are highly specific to invertebrates.

  18. Antibiotic combination therapy can select for broad-spectrum multidrug resistance in Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Vestergaard, Martin; Paulander, Wilhelm; Marvig, Rasmus L.

    2016-01-01

    with the resistance evolved after single-drug exposure. Combination therapy selected for mutants that displayed broad-spectrum resistance, and a major resistance mechanism was mutational inactivation of the repressor gene mexR that regulates the multidrug efflux operon mexAB–oprM. Deregulation of this operon led...... to a broad-spectrum resistance phenotype that decreased susceptibility to the combination of drugs applied during selection as well as to unrelated antibiotic classes. Mutants isolated after single-drug exposure displayed narrow-spectrum resistance and carried mutations in the MexCD–OprJ efflux pump...... regulator gene nfxB conferring ciprofloxacin resistance, or in the gene encoding the non-essential penicillin-binding protein DacB conferring ceftazidime resistance. Reconstruction of resistance mutations by allelic replacement and in vitro fitness assays revealed that in contrast to single antibiotic use...

  19. 宽光谱太阳能电池%Broad-Spectrum Solar Cell

    Institute of Scientific and Technical Information of China (English)

    李承辉; 王锴; 郑玮; 王致祥; 刘建; 游效曾

    2012-01-01

    太阳能电池的光谱响应特性和光电转换效率与光伏材料的微观能带结构及其宏观组装方式密切相关。无论使用哪种光伏材料,普通单结或单层太阳能电池都只能对部分波段的太阳光进行有效利用。宽光谱研究的目标是要使太阳能电池更好地利用太阳光谱所覆盖的全部波段范围的能量,从而提高太阳能电池光电转换效率。本文从化学角度综述了实现宽光谱太阳能电池的基本方法和当前的研究进展,其中包括叠层太阳能电池、中间带太阳能电池、量子点太阳能电池、热光伏太阳能电池、上转换和下转换、分子基柔性太阳能电池等方法。%Due to the energy crisis, utilization of renewable energy sources has been intensively investigated in recent years. Among a variety of renewable energy sources, solar energy is a sustainable alternative option that can be utilized in various ways and can be used for many applications. Converting directly the sunlight to electricity through solar cells is the most common and effective way to use solar energy. The spectral response and overall photo-to-electric energy conversion efficiency of solar cells are closely correlated to the micro band-gap structure and macro assembly process of photovoltaie materials. A solar cell can effectively utilize photons with energy hu close to the semiconductor band gap E,. Photons with energy smaller than the band gap are not absorbed. On the other hand, photons with energy larger than the band gap are absorbed, but the excess energy hu - Eg is not used effectively due to thermalization. Therefore, a normal single junction or single layer solar cell can only use part of the solar radiation no matter what kind of photovoltaic materials are used. Broad-spectrum solar cell aims to use most of the solar energy effectively via several structures or methods: Tandem solar cells, intermediate-band solar cells, quantum dot solar cells

  20. Broad-spectrum physical fitness benefits of recreational football: a systematic review and meta-analysis.

    Science.gov (United States)

    Milanović, Zoran; Pantelić, Saša; Čović, Nedim; Sporiš, Goran; Mohr, Magni; Krustrup, Peter

    2018-01-25

    participants with mild hypertension (11 and 7 mm Hg decrease, respectively) and participants with prehypertension (10 and 7 mm Hg decrease, respectively). Meta-analysis of recreational football determined the impact on resting heart rate as most likely extremely largely beneficial (ES=6.03 beats/min; 95% CI 4.43 to 7.64) when compared with non-active groups. The observed recreational football effect on fat mass was most likely largely beneficial (ES=1.72 kg; 95% CI 0.86 to 2.58) and the effect on countermovement jump (CMJ) performance was most likely very largely beneficial (ES=2.27 cm; 95% CI 1.29 to 3.25) when compared with non-active groups. Possibly beneficial decreases were found in low-density lipoprotein levels (ES=0.21 mmol/L; 95% CI 0.06 to 0.36). Possibly largely beneficial effect was observed for DBP in comparison with continuous running training. Small harmful and unclear results were noted for SBP, fat and lean body mass, body mass index, as well as muscular fitness when compared with running and Zumba training. The present meta-analysis demonstrated multiple broad-spectrum benefits of recreational football on health-related physical fitness compared with no-exercise controls, including improvements in blood pressure, resting heart rate, fat mass, low-density lipoprotein cholesterol and CMJ performance. Additionally, recreational football is efficient and effective as Zumba and continuous running exercise regimens with highlighted social, motivational and competitive components. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  1. Lipophosphonoxins II: Design, Synthesis, and Properties of Novel Broad Spectrum Antibacterial Agents

    Czech Academy of Sciences Publication Activity Database

    Seydlová, G.; Pohl, Radek; Zborníková, Eva; Ehn, Marcel; Šimák, Ondřej; Panova, Natalya; Kolář, M.; Bogdanová, K.; Večeřová, R.; Fišer, R.; Šanderová, Hana; Vítovská, Dragana; Sudzinová, Petra; Pospíšil, Jiří; Benada, Oldřich; Křížek, T.; Sedlák, David; Bartůněk, Petr; Krásný, Libor; Rejman, Dominik

    2017-01-01

    Roč. 60, č. 14 (2017), s. 6098-6118 ISSN 0022-2623 R&D Projects: GA MŠk LO1220; GA MŠk LM2015063; GA ČR(CZ) GBP305/12/G034; GA MŠk(CZ) LM2015055; GA MZd(CZ) NV17-29680A Institutional support: RVO:61388963 ; RVO:61388971 ; RVO:68378050 Keywords : resistant Staphylococcus aureus * cationic steroid antibiotics * antimicrobial peptides Subject RIV: EE - Microbiology, Virology; EE - Microbiology, Virology (MBU-M) OBOR OECD: Microbiology; Microbiology (MBU-M) Impact factor: 6.259, year: 2016

  2. Chlorhexidine gluconate, its properties and applications in endodontics

    Science.gov (United States)

    Mohammadi, Zahed

    2008-01-01

    The major objective in endodontic therapy is to disinfect the entire root canal system. This requires that the pulpal content be eliminated as sources of infection. This goal may be accomplished by mechanical instrumentation and chemical irrigation, in conjunction with medication of the root canal between treatment sessions. Microorganisms and their by-products are considered to be the major cause of pulpal and periradicular pathosis. In order to reduce or eliminate bacteria from the root canal system, various irrigants have been used during treatment. Chlorhexidine is a cationic solution which can be used during treatment. It has a wide range of antimicrobial activity. Furthermore, because of its cationic structure, chlorhexidine has a unique property named substantivity. The purpose of this paper is to review different aspects of chlorhexidine in endodontics. PMID:24265633

  3. Broad-spectrum antibacterial properties of metal-ion doped borate bioactive glasses for clinical applications

    Science.gov (United States)

    Ottomeyer, Megan

    Bioactive glasses with antimicrobial properties can be implemented as coatings on medical devices and implants, as well as a treatment for tissue repair and prevention of common hospital-acquired infections such as MRSA. A borate-containing glass, B3, is also undergoing clinical trials to assess wound-healing properties. The sensitivities of various bacteria to B3, B3-Ag, B3-Ga, and B3-I bioactive glasses were tested. In addition, the mechanism of action for the glasses was studied by spectroscopic enzyme kinetics experiments, Live-Dead staining fluorescence microscopy, and luminescence assays using two gene fusion strains of Escherichia coli. It was found that gram-positive bacteria were more sensitive to all four glasses than gram negative bacteria, and that a single mechanism of action for the glasses is unlikely, as the rates of catalysis for metabolic enzymes as well as membrane permeability were altered after glass exposure.

  4. In vitro antifungal effect of mouth rinses containing chlorhexidine and thymol

    Directory of Open Access Journals (Sweden)

    Ashish Shrestha

    2011-03-01

    Conclusions: Antimicrobial agents used in the study had good in vitro activity against the two Candida species. Mouth rinses containing chlorhexidine showed superior antifungal and fungicidal activities compared to the thymol-containing mouth rinse. Both antimicrobial agents may be suggested for use as topical antifungal agents.

  5. Chitosanase purified from bacterial isolate Bacillus licheniformis of ruined vegetables displays broad spectrum biofilm inhibition.

    Science.gov (United States)

    Muslim, Sahira Nsayef; Al-Kadmy, Israa M S; Hussein, Nadheema Hammood; Mohammed Ali, Alaa Naseer; Taha, Buthainah Mohammed; Aziz, Sarah Naji; Kheraif, Abdulaziz Abdullah Al; Divakar, Darshan Devang; Ramakrishnaiah, Ravikumar

    2016-11-01

    A number of bacterial species produces chitosanases which has variety of applications because of its high biodegradability, non-toxicity and antimicrobial assets. In the present study chitosanase is purified from new bacterial species Bacillus licheniformis from spoiled vegetable. This novel strain of Bacillus licheniformis isolated from spoilt cucumber and pepper samples has the ability to produce the chitosanase enzyme when grown on chitosan substrate. Study also examined its antibiofilm properties against diverse bacterial species with biofilm forming ability. The purified chitosanase inhibited the biofilm formation ability for all Gram-negative and Gram-positive biofilm-forming bacteria [biofilm producers] tested in this study in congo red agar and microtiter plate's methods. Highly antibiofilm activity of chitosanase was recorded against Pseudomonas aeruginosa followed by Klebsiella pneumoniae with reduction of biofilm formation upto 22 and 29%, respectively compared with [100] % of control. Biofilm formation has multiple role including ability to enhance resistance and self-protection from external stress. This chitosanase has promising benefit as antibiofilm agent against biofilm forming pathogenic bacteria and has promising application as alternative antibiofilm agents to combat the growing number of multidrug resistant pathogen-associated infections, especially in situation where biofilms are involved. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Avaliação da atividade antimicrobiana de adesivo ortodôntico associado a verniz de clorexidina e timol na colagem de braquetes Evaluation of antimicrobial activity of orthodontic adhesive associated with chlorhexidine-thymol varnish in bracket bonding

    Directory of Open Access Journals (Sweden)

    Carolina Freire de Carvalho Calabrich

    2010-08-01

    Full Text Available OBJETIVO: avaliar a atividade antimicrobiana da associação de um adesivo ortodôntico com um verniz de clorexidina e timol. MÉTODOS: foram utilizados 32 pré-molares humanos divididos em 4 grupos. O grupo 1 consistiu do grupo controle, no qual o adesivo utilizado para a colagem do braquete não estava associado a nenhum agente antimicrobiano. Os grupos 2, 3 e 4 foram colados com um sistema adesivo associado a um verniz de clorexidina e timol. Os grupos 3 e 4 foram armazenados em água por 7 dias e 30 dias, respectivamente, enquanto os corpos de prova do grupo 2 foram, logo depois da colagem, colocados em ágar semeado com Streptococcus mutans por 48h a 37ºC. RESULTADOS: os grupos experimentais, com exceção do grupo controle, apresentaram atividade antimicrobiana com tendência de redução do seu potencial de ação com maior tempo de imersão em água. CONCLUSÃO: a associação do verniz de clorexidina a um sistema adesivo utilizado em Ortodontia apresenta-se vantajosa pela sua atividade antimicrobiana.OBJECTIVE: To assess the antimicrobial activity resulting from the association of an orthodontic adhesive with chlorhexidine-thymol varnish. METHODS: Thirty-two extracted human premolars were used, divided into four groups. In Group 1, the control group, the adhesive used to bond the bracket was not associated with any antimicrobial agent. Groups 2, 3 and 4 were bonded with an adhesive system associated with chlorhexidine-thymol varnish. Groups 3 and 4 were stored in water for 7 days and 30 days, respectively, while the specimens from group 2 were, soon after bonding, placed on agar seeded with Streptococcus mutans for 48 hours, at 37º C. RESULTS: The experimental groups, with the exception of the control group, showed antimicrobial activity whose action tended to decline commensurately with the amount of time that they remained immersed in water. CONCLUSIONS: The association of chlorhexidine-thymol varnish with an adhesive system used in

  7. The investigation of copper-based impregnated activated carbons prepared from water-soluble materials for broad spectrum respirator applications

    International Nuclear Information System (INIS)

    Smith, J.W.H.; Westreich, P.; Abdellatif, H.; Filbee-Dexter, P.; Smith, A.J.; Wood, T.E.; Croll, L.M.; Reynolds, J.H.; Dahn, J.R.

    2010-01-01

    The preparation of impregnated activated carbons (IACs) from aqueous, copper-containing solutions for broad spectrum gas filtration applications is studied here. Several samples were studied to determine the effect that impregnant loading, impregnant distribution and impregnant recipe had on the overall performance. Dynamic flow testing was used to determine the gas filtration capacity of the IAC samples versus a variety of challenge gases. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) were used to characterize the impregnant distribution on the carbon as a function of impregnant loading. Oven tests were performed to determine the thermal stability of the IAC samples exposed to elevated temperatures. The role impregnant distribution plays in gas filtration capacity and the overall performance of the IAC samples is discussed. The IAC samples prepared in this work were found to have gas filtration capacities as good as or better than broad spectrum respirator carbon samples prepared from the patent literature. IACs impregnated with an aqueous 2.4 M Cu(NO 3 ) 2 /0.04 M H 3 PO 4 .12MoO 3 /4 M HNO 3 solution that were heated to 200 deg. C under argon were found to have the best overall performance of the samples studied in this work.

  8. An aggregated perylene-based broad-spectrum, efficient and label-free quencher for multiplexed fluorescent bioassays.

    Science.gov (United States)

    Liu, Tao; Hu, Rong; Lv, Yi-Fan; Wu, Yuan; Liang, Hao; Huan, Shuang-Yan; Zhang, Xiao-Bing; Tan, Weihong; Yu, Ru-Qin

    2014-08-15

    Fluorescent sensing systems based on the quenching of fluorophores have found wide applications in bioassays. An efficient quencher will endow the sensing system a high sensitivity. The frequently used quenchers are based on organic molecules or nanomaterials, which usually need tedious synthesizing and modifying steps, and exhibit different quenching efficiencies to different fluorophores. In this work, we for the first time report that aggregated perylene derivative can serve as a broad-spectrum and label-free quencher that is able to efficiently quench a variety of fluorophores, such as green, red and far red dyes labeled on DNA. By choosing nucleases as model biomolecules, such a broad-spectrum quencher was then employed to construct a multiplexed bioassay platform through a label-free manner. Due to the high quenching efficiency of the aggregated perylene, the proposed platform could detect nuclease with high sensitivity, with a detection limit of 0.03U/mL for EcoRV, and 0.05U/mL for EcoRI. The perylene quencher does not affect the activity of nuclease, which makes it possible to design post-addition type bioassay platform. Moreover, the proposed platform allows simultaneous and multicolor analysis of nucleases in homogeneous solution, demonstrating its value of potential application in rapid screening of multiple bio-targets. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Changes in Cell Viability of Wounded Fibroblasts following Laser Irradiation in Broad-Spectrum or Infrared Light

    International Nuclear Information System (INIS)

    Hawkins, D.; Abrahamse, H.

    2007-01-01

    Objective. This study aimed to establish if broad-spectrum or infrared (IR) light in combination with laser therapy can assist phototherapy to improve the cell function of wounded cells. Background. The effect of laser light may be partly or completely reduced by broad-spectrum light. Methods. Wounded human skin fibroblasts were irradiated with 5 J/cm2 using a helium-neon laser, a diode laser, or an Nd:YAG laser in the dark, in the light, or in IR. Changes in cell viability were evaluated by cell morphology, ATP cell viability, LDH membrane integrity, and caspase 3/7 as an early marker of apoptosis. Results. Wounded cells exposed to 5 J/cm2 using 632.8 nm in the dark or 830 nm in the light or 1064 nm in the dark showed an increase in ATP viability, an increase in cytokine expression, and a decrease in LDH cytotoxicity indicating that the metabolic activity of the wounded cells was stimulated. Conclusion. Wounded cells irradiated in IR light showed an undesirable thermal effect that was proportional to the duration of exposure.

  10. The investigation of copper-based impregnated activated carbons prepared from water-soluble materials for broad spectrum respirator applications

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.W.H.; Westreich, P.; Abdellatif, H.; Filbee-Dexter, P.; Smith, A.J. [Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia, B3H 3J5 (Canada); Wood, T.E. [3M Company, St. Paul, MN, 55144 (United States); Croll, L.M.; Reynolds, J.H. [3M Canada Company, Brockville, Ontario, K6V 5V8 (Canada); Dahn, J.R., E-mail: jeff.dahn@dal.ca [Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia, B3H 3J5 (Canada); Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, B3H 4J3 (Canada)

    2010-08-15

    The preparation of impregnated activated carbons (IACs) from aqueous, copper-containing solutions for broad spectrum gas filtration applications is studied here. Several samples were studied to determine the effect that impregnant loading, impregnant distribution and impregnant recipe had on the overall performance. Dynamic flow testing was used to determine the gas filtration capacity of the IAC samples versus a variety of challenge gases. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) were used to characterize the impregnant distribution on the carbon as a function of impregnant loading. Oven tests were performed to determine the thermal stability of the IAC samples exposed to elevated temperatures. The role impregnant distribution plays in gas filtration capacity and the overall performance of the IAC samples is discussed. The IAC samples prepared in this work were found to have gas filtration capacities as good as or better than broad spectrum respirator carbon samples prepared from the patent literature. IACs impregnated with an aqueous 2.4 M Cu(NO{sub 3}){sub 2}/0.04 M H{sub 3}PO{sub 4}.12MoO{sub 3}/4 M HNO{sub 3} solution that were heated to 200 deg. C under argon were found to have the best overall performance of the samples studied in this work.

  11. Comparison between pathogen directed antibiotic treatment and empirical broad spectrum antibiotic treatment in patients with community acquired pneumonia: a prospective randomised study

    NARCIS (Netherlands)

    van der Eerden, M. M.; Vlaspolder, F.; de Graaff, C. S.; Groot, T.; Bronsveld, W.; Jansen, H. M.; Boersma, W. G.

    2005-01-01

    Background: There is much controversy about the ideal approach to the management of community acquired pneumonia ( CAP). Recommendations differ from a pathogen directed approach to an empirical strategy with broad spectrum antibiotics. Methods: In a prospective randomised open study performed

  12. Pentocin MQ1: A Novel, Broad-Spectrum, Pore-Forming Bacteriocin From Lactobacillus pentosus CS2 With Quorum Sensing Regulatory Mechanism and Biopreservative Potential

    Directory of Open Access Journals (Sweden)

    Samson B. Wayah

    2018-03-01

    Full Text Available Micrococcus luteus, Listeria monocytogenes, and Bacillus cereus are major food-borne pathogenic and spoilage bacteria. Emergence of antibiotic resistance and consumer demand for foods containing less of chemical preservatives led to a search for natural antimicrobials. A study aimed at characterizing, investigating the mechanism of action and regulation of biosynthesis and evaluating the biopreservative potential of pentocin from Lactobacillus pentosus CS2 was conducted. Pentocin MQ1 is a novel bacteriocin isolated from L. pentosus CS2 of coconut shake origin. The purification strategy involved adsorption-desorption of bacteriocin followed by RP-HPLC. It has a molecular weight of 2110.672 Da as determined by MALDI-TOF mass spectrometry and a molar extinction value of 298.82 M−1 cm−1. Pentocin MQ1 is not plasmid-borne and its biosynthesis is regulated by a quorum sensing mechanism. It has a broad spectrum of antibacterial activity, exhibited high chemical, thermal and pH stability but proved sensitive to proteolytic enzymes. It is potent against M. luteus, B. cereus, and L. monocytogenes at micromolar concentrations. It is quick-acting and exhibited a bactericidal mode of action against its targets. Target killing was mediated by pore formation. We report for the first time membrane permeabilization as a mechanism of action of the pentocin from the study against Gram-positive bacteria. Pentocin MQ1 is a cell wall-associated bacteriocin. Application of pentocin MQ1 improved the microbiological quality and extended the shelf life of fresh banana. This is the first report on the biopreservation of banana using bacteriocin. These findings place pentocin MQ1 as a potential biopreservative for further evaluation in food and medical applications.

  13. A Strategy for Generating a Broad-Spectrum Monoclonal Antibody and Soluble Single-Chain Variable Fragments against Plant Potyviruses

    Science.gov (United States)

    Liu, Han-Lin; Lin, Wei-Fang; Hu, Wen-Chi; Lee, Yung-An

    2015-01-01

    Potyviruses are major pathogens that often cause mixed infection in calla lilies. To reduce the time and cost of virus indexing, a detection method for the simultaneous targeting of multiple potyviruses was developed by generating a broad-spectrum monoclonal antibody (MAb) for detecting the greatest possible number of potyviruses. The conserved 121-amino-acid core regions of the capsid proteins of Dasheen mosaic potyvirus (DsMV), Konjak mosaic potyvirus (KoMV), and Zantedeschia mild mosaic potyvirus (ZaMMV) were sequentially concatenated and expressed as a recombinant protein for immunization. After hybridoma cell fusion and selection, one stable cell line that secreted a group-specific antibody, named C4 MAb, was selected. In the reaction spectrum test, the C4 MAb detected at least 14 potyviruses by indirect enzyme-linked immunosorbent assay (I-ELISA) and Western blot analysis. Furthermore, the variable regions of the heavy (VH) and light (VL) chains of the C4 MAb were separately cloned and constructed as single-chain variable fragments (scFvs) for expression in Escherichia coli. Moreover, the pectate lyase E (PelE) signal peptide of Erwinia chrysanthemi S3-1 was added to promote the secretion of C4 scFvs into the medium. According to Western blot analysis and I-ELISA, the soluble C4 scFv (VL-VH) fragment showed a binding specificity similar to that of the C4 MAb. Our results demonstrate that a recombinant protein derived from fusion of the conserved regions of viral proteins has the potential to produce a broad-spectrum MAb against a large group of viruses and that the PelE signal peptide can improve the secretion of scFvs in E. coli. PMID:26209665

  14. The Probiotic Compound VSL#3 Modulates Mucosal, Peripheral, and Systemic Immunity Following Murine Broad-Spectrum Antibiotic Treatment

    Directory of Open Access Journals (Sweden)

    Ira Ekmekciu

    2017-05-01

    Full Text Available There is compelling evidence linking the commensal intestinal microbiota with host health and, in turn, antibiotic induced perturbations of microbiota composition with distinct pathologies. Despite the attractiveness of probiotic therapy as a tool to beneficially alter the intestinal microbiota, its immunological effects are still incompletely understood. The aim of the present study was to assess the efficacy of the probiotic formulation VSL#3 consisting of eight distinct bacterial species (including Streptococcus thermophilus, Bifidobacterium breve, B. longum, B. infantis, Lactobacillus acidophilus, L. plantarum, L. paracasei, and L. delbrueckii subsp. Bulgaricus in reversing immunological effects of microbiota depletion as compared to reassociation with a complex murine microbiota. To address this, conventional mice were subjected to broad-spectrum antibiotic therapy for 8 weeks and perorally reassociated with either VSL#3 bacteria or a complex murine microbiota. VSL#3 recolonization resulted in restored CD4+ and CD8+ cell numbers in the small and large intestinal lamina propria as well as in B220+ cell numbers in the former, whereas probiotic intervention was not sufficient to reverse the antibiotic induced changes of respective cell populations in the spleen. However, VSL#3 application was as efficient as complex microbiota reassociation to attenuate the frequencies of regulatory T cells, activated dendritic cells and memory/effector T cells in the small intestine, colon, mesenteric lymph nodes, and spleen. Whereas broad-spectrum antibiotic treatment resulted in decreased production of cytokines such as IFN-γ, IL-17, IL-22, and IL-10 by CD4+ cells in respective immunological compartments, VSL#3 recolonization was sufficient to completely recover the expression of the anti-inflammatory cytokine IL-10 without affecting pro-inflammatory mediators. In summary, the probiotic compound VSL#3 has an extensive impact on mucosal, peripheral, and

  15. Mechanisms of Broad-Spectrum Antiemetic Efficacy of Cannabinoids against Chemotherapy-Induced Acute and Delayed Vomiting

    Directory of Open Access Journals (Sweden)

    Nissar A. Darmani

    2010-09-01

    Full Text Available Chemotherapy-induced nausea and vomiting (CINV is a complex pathophysiological condition and consists of two phases. The conventional CINV neurotransmitter hypothesis suggests that the immediate phase is mainly due to release of serotonin (5-HT from the enterochromaffin cells in the gastrointestinal tract (GIT, while the delayed phase is a consequence of release of substance P (SP in the brainstem. However, more recent findings argue against this simplistic neurotransmitter and anatomical view of CINV. Revision of the hypothesis advocates a more complex, differential and overlapping involvement of several emetic neurotransmitters/modulators (e.g. dopamine, serotonin, substance P, prostaglandins and related arachidonic acid derived metabolites in both phases of emesis occurring concomitantly in the brainstem and in the GIT enteric nervous system (ENS [1]. No single antiemetic is currently available to completely prevent both phases of CINV. The standard antiemetic regimens include a 5-HT3 antagonist plus dexamethasone for the prevention of acute emetic phase, combined with an NK1 receptor antagonist (e.g. aprepitant for the delayed phase. Although NK1 antagonists behave in animals as broad-spectrum antiemetics against different emetogens including cisplatin-induced acute and delayed vomiting, by themselves they are not very effective against CINV in cancer patients. Cannabinoids such as D9-THC also behave as broad-spectrum antiemetics against diverse emetic stimuli as well as being effective against both phases of CINV in animals and patients. Potential side effects may limit the clinical utility of direct-acting cannabinoid agonists which could be avoided by the use of corresponding indirect-acting agonists. Cannabinoids (both phyto-derived and synthetic behave as agonist antiemetics via the activation of cannabinoid CB1 receptors in both the brainstem and the ENS emetic loci. An endocannabinoid antiemetic tone may exist since inverse CB1

  16. Chlorhexidine Keratitis: Safety of Chlorhexidine as a Facial Antiseptic.

    Science.gov (United States)

    Steinsapir, Kenneth D; Woodward, Julie A

    2017-01-01

    Effective antiseptic to reduce surgical site infections is a cornerstone of modern surgery. Chlorhexidine gluconate-based antiseptics are among the most effective of these products. Unfortunately, chlorhexidine solutions are toxic to the cornea and middle ear, and they pose a splash risk to both the patient and health care personnel. To examine the clinical evidence that led to the disavowal of chlorhexidine antiseptic solution for use on the face and head. Reference searches were performed using PubMed, Embase, and LexisNexis databases without restriction to the date of publication, language, or study setting. The literature revealed 11 sentinel cases of severe chlorhexidine-related keratitis in the late 1980s. These cases are reviewed together with data on ototoxicity and alternative products to understand why chlorhexidine solution should not be used on the face and scalp. Chlorhexidine antiseptic solutions are highly effective. However, they pose a risk to the middle ear and have the potential to irreversibly damage the cornea with a minimal splash exposure. Povidone-iodine is a safe and effective alternative.

  17. New insights into broad spectrum communities of the Early Holocene Near East: The birds of Hallan Çemi

    Science.gov (United States)

    Zeder, Melinda A.; Spitzer, Megan D.

    2016-11-01

    The Early Holocene in Near East was a pivotal transitional period that witnessed dramatic changes in climate and environment, human settlement, major changes in subsistence strategies focusing on a broad range of different plant and animal resources, and a radical restructuring of social relations. The remarkable corpus of avifauna from the Early Holocene site of Hallan Çemi in southeastern Turkey sheds new light on key issues about this dynamic period that has been termed the ;Broad Spectrum Revolution;. The avifauna from this important site demonstrate how Hallan Çemi occupants took advantage of the site's strategic location at the junction of multiple environmental zones by extracting a diverse range of seasonally available resources from both near-by and more distant eco-zones to cobble together a stable subsistence economy capable of supporting this small community throughout the year. They give testimony to the impacts of resource utilization over time, especially on species unable to rebound from sustained human hunting. At the same time, they show how Hallan Çemi residents mitigated these impacts by replacing depleted resources with alternative, more resilient ones that could be more sustainably harvested. They open a window onto the growing investment in feasting and ritual activity that helped bind this community together. In so doing they provide a means of empirically evaluating the efficacy of contrasting explanatory frameworks for the Broad Spectrum Revolution that gave rise to the subsequent domestication of plant and animals in the Near East. Contrary to frameworks that cast these developments as responses to resource depression, lessons learned from the Hallan Çemi avifauna lend support to frameworks that emphasize the human capacity to strategically target, capitalize, and improve upon circumscribed resource rich environments in a way that permits more permanent occupation of these niches. And they underscore the degree to which social and

  18. Development and Evaluation of Mucoadhesive Chlorhexidine Tablet ...

    African Journals Online (AJOL)

    Purpose: To formulate mucoadhesive chlorhexidine tablets and evaluate their drug release characteristics and mechanism. Methods: Chlorhexidine buccal adhesive tablets were prepared by direct compression using a blend of hydroxypropyl methylcellulose (HPMC) and chitosan as the bioadhesive polymers.

  19. IgE-mediated allergy to chlorhexidine

    DEFF Research Database (Denmark)

    Garvey, Lene Heise; Krøigaard, Mogens; Poulsen, Lars K.

    2007-01-01

    Investigations at the Danish Anesthesia Allergy Centre have included testing for allergy to chlorhexidine since 1999.......Investigations at the Danish Anesthesia Allergy Centre have included testing for allergy to chlorhexidine since 1999....

  20. In vitro antimicrobial activity of irreversible hydrocolloid impressions against 12 oral microorganisms

    OpenAIRE

    Casemiro,Luciana Assirati; Pires-de-Souza,Fernanda de Carvalho Panzeri; Panzeri,Heitor; Martins,Carlos Henrique Gomes; Ito,Isabel Yoko

    2007-01-01

    This study evaluated in vitro the antimicrobial activity of irreversible hydrocolloids (one containing an antimicrobial agent) prepared with water or with a 0.2% chlorhexidine digluconate solution against 12 strains of the oral microbiota. Twenty specimens (0.5 x 1.0 cm) for each group (1. Jeltrate mixed with water; 2. Jeltrate mixed with 0.2% chlorhexidine digluconate solution; 3. Greengel mixed with water; 4. Greengel mixed with 0.2% chlorhexidine digluconate solution) were prepared under s...

  1. A novel alkaloid from marine-derived actinomycete Streptomyces xinghaiensis with broad-spectrum antibacterial and cytotoxic activities.

    Directory of Open Access Journals (Sweden)

    Wence Jiao

    Full Text Available Due to the increasing emergence of drug-resistant bacteria and tumor cell lines, novel antibiotics with antibacterial and cytotoxic activities are urgently needed. Marine actinobacteria are rich sources of novel antibiotics, and here we report the discovery of a novel alkaloid, xinghaiamine A, from a marine-derived actinomycete Streptomyces xinghaiensis NRRL B24674(T. Xinghaiamine A was purified from the fermentation broth, and its structure was elucidated based on extensive spectroscopic analysis, including 1D and 2D NMR spectrum as well as mass spectrometry. Xinghaiamine A was identified to be a novel alkaloid with highly symmetric structure on the basis of sulfoxide functional group, and sulfoxide containing compound has so far never been reported in microorganisms. Biological assays revealed that xinghaiamine A exhibited broad-spectrum antibacterial activities to both Gram-negative persistent hospital pathogens (e.g. Acinetobacter baumannii, Pseudomonas aeruginosa and Escherichia coli and Gram-positive ones, which include Staphylococcus aureus and Bacillus subtilis. In addition, xinghaiamine A also exhibited potent cytotoxic activity to human cancer cell lines of MCF-7 and U-937 with the IC50 of 0.6 and 0.5 µM, respectively.

  2. A broad-spectrum, efficient and nontransgenic approach to control plant viruses by application of salicylic acid and jasmonic acid.

    Science.gov (United States)

    Shang, Jing; Xi, De-Hui; Xu, Fei; Wang, Shao-Dong; Cao, Sen; Xu, Mo-Yun; Zhao, Ping-Ping; Wang, Jian-Hui; Jia, Shu-Dan; Zhang, Zhong-Wei; Yuan, Shu; Lin, Hong-Hui

    2011-02-01

    Plant viruses cause many diseases that lead to significant economic losses. However, most of the approaches to control plant viruses, including transgenic processes or drugs are plant-species-limited or virus-species-limited, and not very effective. We introduce an application of jasmonic acid (JA) and salicylic acid (SA), a broad-spectrum, efficient and nontransgenic method, to improve plant resistance to RNA viruses. Applying 0.06 mM JA and then 0.1 mM SA 24 h later, enhanced resistance to Cucumber mosaic virus (CMV), Tobacco mosaic virus (TMV) and Turnip crinkle virus (TCV) in Arabidopsis, tobacco, tomato and hot pepper. The inhibition efficiency to virus replication usually achieved up to 80-90%. The putative molecular mechanism was investigated. Some possible factors affecting the synergism of JA and SA have been defined, including WRKY53, WRKY70, PDF1.2, MPK4, MPK2, MPK3, MPK5, MPK12, MPK14, MKK1, MKK2, and MKK6. All genes involving in the synergism of JA and SA were investigated. This approach is safe to human beings and environmentally friendly and shows potential as a strong tool for crop protection against plant viruses.

  3. Broad-spectrum antiviral activity of chebulagic acid and punicalagin against viruses that use glycosaminoglycans for entry

    Science.gov (United States)

    2013-01-01

    Background We previously identified two hydrolyzable tannins, chebulagic acid (CHLA) and punicalagin (PUG) that blocked herpes simplex virus type 1 (HSV-1) entry and spread. These compounds inhibited viral glycoprotein interactions with cell surface glycosaminoglycans (GAGs). Based on this property, we evaluated their antiviral efficacy against several different viruses known to employ GAGs for host cell entry. Results Extensive analysis of the tannins’ mechanism of action was performed on a panel of viruses during the attachment and entry steps of infection. Virus-specific binding assays and the analysis of viral spread during treatment with these compounds were also conducted. CHLA and PUG were effective in abrogating infection by human cytomegalovirus (HCMV), hepatitis C virus (HCV), dengue virus (DENV), measles virus (MV), and respiratory syncytial virus (RSV), at μM concentrations and in dose-dependent manners without significant cytotoxicity. Moreover, the natural compounds inhibited viral attachment, penetration, and spread, to different degrees for each virus. Specifically, the tannins blocked all these steps of infection for HCMV, HCV, and MV, but had little effect on the post-fusion spread of DENV and RSV, which could suggest intriguing differences in the roles of GAG-interactions for these viruses. Conclusions CHLA and PUG may be of value as broad-spectrum antivirals for limiting emerging/recurring viruses known to engage host cell GAGs for entry. Further studies testing the efficacy of these tannins in vivo against certain viruses are justified. PMID:23924316

  4. Novel Hybrid Anticonvulsants Derived from Pyrrolidine-2,5-dione Scaffold with Broad Spectrum of Activity in the Preclinical Studies.

    Science.gov (United States)

    Kaminski, Krzysztof

    2017-01-01

    The multifunctional ligands application is an emerging approach in drug delivery, mainly in the treatment of diseases with complex pathology, such as Alzheimer's, cancer, and epilepsy. Using this method many biomolecules with different properties are combined to form a single unit that can provide a complex broad spectrum activity. Thus, a new type of hybrid anticonvulsants based on the pyrrolidine-2,5-dione frame are detailed with the aim of acquiring more effective antiepileptic drugs (AED) that could suppress various human convulsions. These hybrid molecules attach to the chemical particles of clinically relevant AEDs such as ethosuximide, levetiracetam, and lacosamide. As a result of this hybridization process the compounds obtained were effective in three most important animal epilepsy models, namely the maximal electroshock seizure (MES) test, the subcutaneous pentylenetetrazole (scPTZ) test, and the six-Hertz (6 Hz) model in mice. These substances displayed wider spectrum of protection, more potent efficacy, and better safety profile than the aforementioned AEDs. Several compounds were also active in the formalin model of persistent pain in mice. The in vitro ligand binding studies have proved that the most conceivable molecular mechanism of anticonvulsant and antinociceptive action was the influence on the neuronal voltage-sensitive sodium and L-type calcium channels. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  5. A universal aptameric biosensor: Multiplexed detection of small analytes via aggregated perylene-based broad-spectrum quencher.

    Science.gov (United States)

    Hu, Rong; Zhang, Xi; Xu, Qiang; Lu, Dan-Qing; Yang, Yun-Hui; Xu, Quan-Qing; Ruan, Qiong; Mo, Liu-Ting; Zhang, Xiao-Bing

    2017-06-15

    A universal aptameric system based on the taking advantage of double-stranded DNA/perylene diimide (dsDNA/PDI) as the signal probe was developed for multiplexed detection of small molecules. Aptamers are single-stranded DNA or RNA oligonucleotides which are selected in vitro by a process known as systematic evolution of ligands by exponential enrichment. In this work, we synthesized a new kind of PDI and reported this aggregated PDI could quench the double-stranded DNA (dsDNA)-labeled fluorophores with a high quenching efficiency. The quenching efficiencies on the fluorescence of FAM, TAMRA and Cy5 could reach to 98.3%±0.9%, 97.2%±0.6% and 98.1%±1.1%, respectively. This broad-spectrum quencher was then adopted to construct a multicolor biosensor via a label-free approach. A structure-switching-triggered enzymatic recycling amplification was employed for signal amplification. High quenching efficiency combined with autocatalytic target recycling amplification afforded the biosensor with high sensitivity towards small analytes. For other targets, changing the corresponding aptamer can achieve the goal. The quencher did not interfere with the catalytic activity of nuclease. The biosensor could be manipulated with similar sensitivity no matter in pre-addition or post-addition manner. Moreover, simultaneous and multiplexed analysis of several small molecules in homogeneous solution was achieved, demonstrating its potential application in the rapid screening of multiple biotargets. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Broad-spectrum detection of H5 subtype influenza A viruses with a new fluorescent immunochromatography system.

    Directory of Open Access Journals (Sweden)

    Akira Sakurai

    Full Text Available Immunochromatography (IC is an antigen-detection assay that plays an important role in the rapid diagnosis of influenza virus because the protocol is short time and easy to use. Despite the usability of IC, the sensitivity is approximately 10(3 pfu per reaction. In addition, antigen-antibody interaction-based method cannot be used for the detection of influenza viruses with major antigenic change. In this study, we established the use of fluorescent immunochromatography (FLIC to detect a broad spectrum of H5 subtype influenza A viruses. This method has improved sensitivity 10-100 fold higher than traditional IC because of the use of fluorescent conjugated beads. Our Type-E FLIC kit detected all of the H5 subtype influenza viruses that were examined, as well as recombinant hemagglutinin (HA proteins (rHAs belonging to the Eurasian H5 subtype viruses and the Type-N diagnosed North American H5 subtype influenza A viruses. Thus, this kit has the improved potential to detect H5 subtype influenza viruses of different clades with both Type-E and Type-N FLIC kits. Compared with PCR-based diagnosis, FLIC has a strong advantage in usability, because the sample preparation required for FLIC is only mix-and-drop without any additional steps such as RNA extraction. Our results can provide new strategies against the spread and transmission of HPAI H5N1 viruses in birds and mammals including humans.

  7. Broad-spectrum health improvements with one year of soccer training in inactive mildly hypertensive middle-aged women.

    Science.gov (United States)

    Krustrup, P; Skoradal, M-B; Randers, M B; Weihe, P; Uth, J; Mortensen, J; Mohr, M

    2017-12-01

    The study tested the hypothesis that long-term soccer training has positive impact on cardiovascular profile, body composition, bone health, and physical capacity in inactive, pre-menopausal women with mild hypertension. The study applied a randomized controlled design in which physically inactive middle-aged women were separated into a soccer training group (n=19; SOC) and a control group (n=12; CON). SOC performed 128±29 (±SD) one-h small-sided soccer training sessions over one year. Blood pressure, body composition, blood lipid profile, and fitness level were determined pre- and post-intervention. Over one year, mean arterial pressure decreased more in SOC than in CON (-5±7 vs +4±5 mmHg; Pendurance level 1 (122±105 vs 2±21%) and 20-m sprint performance (6±6 vs -1±2%) increased more (Ptraining resulted in broad-spectrum improvements in the health profile of untrained, pre-menopausal women with mild hypertension, including cardiovascular, metabolic, and musculo-skeletal benefits. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Weak turbulence and broad-spectrum excitation in a nonmagnetized electron beam via second-harmonic generation

    International Nuclear Information System (INIS)

    Bogdanov, A.T.

    1990-01-01

    The nonlinear evolution of an initially monoenergetic [ν-bar(t = 0) = (0,0,u)] electron beam propagating in a nonmagnetized dielectric medium of permittivity ε > 1, with initial velocity u ≥ c/√ε (where c is the vacuum speed of light) is investigated. The specific instability of the beam under such conditions is the cause of the generation of a broad spectrum of transverse electromagnetic waves coupled to the simultaneous excitation of the second harmonic of the beam's oscillations, both at the expense of the beam's initial kinetic energy. The system of self-consistent nonlinear equations, describing the particle-field dynamics, is treated in the spirit of the weak-turbulence approach. The integrals of the resulting nonlinear system of equations for the amplitudes of the fields of the electron density are used to evaluate the spectral distribution of the amplitudes in the saturation phase, and hence the efficiency of the transformation of the beam's energy into electromagnetic radiation as a function of the width of the spectrum of the initially present electromagnetic fluctuations. A substantial increase in this efficiency is observed in comparison with the single-mode case. (author)

  9. Marker-assisted introgression of broad-spectrum blast resistance genes into the cultivated MR219 rice variety.

    Science.gov (United States)

    Miah, Gous; Rafii, Mohd Y; Ismail, Mohd R; Puteh, Adam B; Rahim, Harun A; Latif, Mohammad A

    2017-07-01

    The rice cultivar MR219 is famous for its better yield and long and fine grain quality; however, it is susceptible to blast disease. The main objective of this study was to introgress blast resistance genes into MR219 through marker-assisted selection (MAS). The rice cultivar MR219 was used as the recurrent parent, and Pongsu Seribu 1 was used as the donor. Marker-assisted foreground selection was performed using RM6836 and RM8225 to identify plants possessing blast resistance genes. Seventy microsatellite markers were used to estimate recurrent parent genome (RPG) recovery. Our analysis led to the development of 13 improved blast resistant lines with Piz, Pi2 and Pi9 broad-spectrum blast resistance genes and an MR219 genetic background. The RPG recovery of the selected improved lines was up to 97.70% with an average value of 95.98%. Selected improved lines showed a resistance response against the most virulent blast pathogen pathotype, P7.2. The selected improved lines did not express any negative effect on agronomic traits in comparison with MR219. The research findings of this study will be a conducive approach for the application of different molecular techniques that may result in accelerating the development of new disease-resistant rice varieties, which in turn will match rising demand and food security worldwide. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  10. Antimicrobial activity of Caesalpinia pulcherrima, Euphorbia hirta and Asystasia gangeticum.

    Science.gov (United States)

    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.

  11. Comparison of antibacterial efficacy of coconut oil and chlorhexidine on Streptococcus mutans: An in vivo study.

    Science.gov (United States)

    Peedikayil, Faizal C; Remy, Vimal; John, Seena; Chandru, T P; Sreenivasan, Prathima; Bijapur, Gufran Ahmed

    2016-01-01

    Streptococcus mutans is the most common organism causing dental caries. Various chemotherapeutic agents are available that help in treating the bacteria, with each having their own merits and demerits. Recent research has shown that coconut oil has anti-inflammatory and antimicrobial action. Therefore, the present was conducted to determine the antibacterial efficacy of coconut oil and to compare it with chlorhexidine. A total of fifty female children aged 8-12 years were included in the study. Twenty five children were randomly distributed to each group, i.e., the study group (coconut oil) and the control group (chlorhexidine). The participants were asked to routinely perform oil swishing with coconut oil and chlorhexidine and rinse every day in the morning after brushing for 2-3 minutes. S. mutans in saliva and plaque were determined using a chairside method, i.e., the Dentocult SM Strip Mutans test. Patients were instructed to continue oil swishing for 30 days. S. mutans . counts in plaque and saliva on day 1, day 15, and day 30 were recorded and the results were compared using Wilcoxon matched pairs signed ranks test. The results showed that there is a statistically significant decrease in S. mutans . count from coconut oil as well as chlorhexidine group from baseline to 30 days. The study also showed that in comparison of coconut oil and chlorhexidine there is no statistically significant change regarding the antibacterial efficacy. Coconut oil is as effective as chlorhexidine in the reduction of S. mutans .

  12. Formulation and stability of an extemporaneous 0.02% chlorhexidine digluconate ophthalmic solution.

    Science.gov (United States)

    Lin, Shu-Chiao; Huang, Chih-Fen; Shen, Li-Jiuan; Wang, Hsueh-Ju; Lin, Chia-Yu; Wu, Fe-Lin Lin

    2015-12-01

    Acanthamoeba keratitis is difficult to treat because Acanthamoeba cysts are resistant to the majority of antimicrobial agents. Despite the efficacy of 0.02% chlorhexidine in treating Acanthamoeba keratitis, a lack of data in the literature regarding the formulation's stability limits its clinical use. The objective of this study was to develop an optimal extemporaneous 0.02% chlorhexidine digluconate ophthalmic formulation for patients in need. With available active pharmaceutical ingredients, 0.02% chlorhexidine digluconate sample solutions were prepared by diluting with BSS Plus Solution or acetate buffer. Influences of the buffer, type of container, and temperature under daily-open condition were assessed based on the changes of pH values and chlorhexidine concentrations of the test samples weekly. To determine the beyond-use date, the optimal samples were stored at 2-8°C or room temperature, and analyzed at time 0 and at Week 1, Week 2, Week 3, Week 4, Week 5, Week 8, Week 12, and Week 24. Despite chlorhexidine exhibiting better stability in acetate buffer than in BSS solution, its shelf-life was stability at 2-25°C for 6 months after being sealed and for 1 month after opening. This finding will enable us to prepare 0.02% chlorhexidine digluconate ophthalmic solutions based on a doctor's prescription. Copyright © 2014. Published by Elsevier B.V.

  13. Naturally occurring broad-spectrum powdery mildw resistance in a central American tomato accession is caused by loss of Mlo function

    NARCIS (Netherlands)

    Bai, Y.; Pavan, S.N.C.; Zheng, Z.; Zappel, N.F.; Reinstadler, A.; Lotti, C.; Giovanni, de C.; Ricciardi, L.; Lindhout, P.; Visser, R.G.F.; Theres, K.; Panstruga, R.

    2008-01-01

    The resistant cherry tomato (Solanum lycopersicum var. cerasiforme) line LC-95, derived from an accession collected in Ecuador, harbors a natural allele (ol-2) that confers broad-spectrum and recessively inherited resistance to powdery mildew (Oidium neolycopersici). As both the genetic and

  14. Durable broad-spectrum powdery mildew resistance in pea er1 plants is conferred by natural loss-of-function mutations in PsMLO1

    NARCIS (Netherlands)

    Humphry, M.; Reinstädler, A.; Ivanov, S.; Bisseling, T.; Panstruga, R.

    2011-01-01

    Loss-of-function alleles of plant-specific MLO (Mildew Resistance Locus O) genes confer broad-spectrum powdery mildew resistance in monocot (barley) and dicot (Arabidopsis thaliana, tomato) plants. Recessively inherited powdery mildew resistance in pea (Pisum sativum) er1 plants is, in many aspects,

  15. Draft Genome Sequence of Streptomyces sp. Strain Wb2n-11, a Desert Isolate with Broad-Spectrum Antagonism against Soilborne Phytopathogens

    Energy Technology Data Exchange (ETDEWEB)

    Köberl, Martina; White, Richard A.; Erschen, Sabine; El-Arabi, Tarek F.; Jansson, Janet K.; Berg, Gabriele

    2015-08-06

    Streptomyces sp. strain Wb2n-11, isolated from native desert soil, exhibited broad-spectrum antagonism against plant pathogenic fungi, bacteria and nematodes. The 8.2 Mb draft genome reveals genes putatively responsible for its promising biocontrol activity and genes which enable the soil bacterium to directly interact beneficially with plants.

  16. A highly sensitive, multiplex broad-spectrum PCR-DNA-enzyme immunoassay and reverse hybridization assay for rapid detection and identification of Chlamydia trachomatis serovars.

    NARCIS (Netherlands)

    Quint, K.D.; Doorn, L.J. van; Kleter, B.; Koning, M.N. de; Munckhof, H.A. van den; Morre, S.A.; Harmsel, B. ter; Weiderpass, E.; Harbers, G.; Melchers, W.J.G.; Quint, W.G.V.

    2007-01-01

    Chlamydia trachomatis (Ct) comprises distinct serogroups and serovars. The present study evaluates a novel Ct amplification, detection, and genotyping method (Ct-DT assay). The Ct-DT amplification step is a multiplex broad-spectrum PCR for the cryptic plasmid and the VD2-region of ompl. The Ct-DT

  17. Spectral properties of plant leaves pertaining to urban landscape design of broad-spectrum solar ultraviolet radiation reduction

    Science.gov (United States)

    Yoshimura, Haruka; Zhu, Hui; Wu, Yunying; Ma, Ruijun

    2010-03-01

    Human exposure to harmful ultraviolet (UV) radiation has important public health implications. Actual human exposure to solar UV radiation depends on ambient UV irradiance, and the latter is influenced by ground reflection. In urban areas with higher reflectivity, UV exposure occurs routinely. To discover the solar UV radiation regulation mechanism of vegetation, the spectral reflectance and transmittance of plant leaves were measured with a spectrophotometer. Typically, higher plants have low leaf reflectance (around 5%) and essentially zero transmittance throughout the UV region regardless of plant species and seasonal change. Accordingly, incident UV radiation decreases to 5% by being reflected and is reduced to zero by passing through a leaf. Therefore, stratified structures of vegetation are working as another terminator of UV rays, protecting whole terrestrial ecosystems, while vegetation at waterfronts contributes to protect aquatic ecosystems. It is possible to protect the human population from harmful UV radiation by urban landscape design of tree shade and the botanical environment. Even thin but uniformly distributed canopy is effective in attenuating UV radiation. To intercept diffuse radiation, UV screening by vertical structures such as hedges should be considered. Reflectivity of vegetation is around 2%, as foliage surfaces reduce incident UV radiation via reflection, while also eliminating it by transmittance. Accordingly, vegetation reduces incident UV radiation to around 2% by reflection. Vegetation influence on ambient UV radiation is broad-spectrum throughout the UV region. Only trees provide cool UV protective shade. Urban landscapes aimed at abating urban heat islands integrated with a reduction of human UV over-exposure would contribute to mitigation of climate change.

  18. Broad spectrum reactivity versus subtype specificity-trade-offs in serodiagnosis of influenza A virus infections by competitive ELISA.

    Science.gov (United States)

    Postel, A; Ziller, M; Rudolf, M; Letzel, T; Ehricht, Ralf; Pourquier, P; Dauber, M; Grund, C; Beer, Martin; Harder, T C

    2011-04-01

    Avian influenza viruses (AIVs) of the H5 and H7 subtypes can cause substantial economic losses in the poultry industry and are a potential threat to public health. Serosurveillance of poultry populations is an important monitoring tool and can also be used for control of vaccination campaigns. The purpose of this study was to develop broadly reactive, yet subtype-specific competitive ELISAs (cELISAs) for the specific detection of antibodies to the notifiable AIV subtypes H5 and H7 as an alternative to the gold standard haemagglutination inhibition assay (HI). Broadly reacting monoclonal competitor antibodies (mAbs) and genetically engineered subtype H5 or H7 haemagglutinin antigen, expressed and in vivo biotinylated in insect cells, were used to develop the cELISAs. Sera from galliform species and water fowl (n=793) were used to evaluate the performance characteristics of the cELISAs. For the H5 specific cELISA, 98.1% test sensitivity and 91.5% test specificity (97.7% and 90.2% for galliforms; 98.9% and 92.6% for waterfowl), and for the H7 cELISA 97.3% sensitivity and 91.8% specificity (95.3% and 98.9% for galliforms; 100% and 82.7% for waterfowl) were reached when compared to HI. The use of competitor mAbs with broad spectrum reactivity within an AIV haemagglutinin subtype allowed for homogenous detection with high sensitivity of subtype-specific antibodies induced by antigenically widely distinct isolates including antigenic drift variants. However, a trade-off regarding sensitivity versus nonspecific detection of interfering antibodies induced by phylo- and antigenically closely related subtypes, e.g., H5 versus H2 and H7 versus H15, must be considered. The observed intersubtype antibody cross-reactivity remains a disturbance variable in AIV subtype-specific serodiagnosis which negatively affects specificity. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Application of the broad-spectrum bacteriocin enterocin AS-48 to inhibit Bacillus coagulans in canned fruit and vegetable foods.

    Science.gov (United States)

    Lucas, R; Grande, M A J; Abriouel, H; Maqueda, M; Ben Omar, N; Valdivia, E; Martínez-Cañamero, M; Gálvez, A

    2006-10-01

    The enterococcal bacteriocin (enterocin) AS-48 is a broad-spectrum cyclic peptide. Enterocin AS-48 was tested against Bacillus coagulans in three vegetable canned foods: tomato paste (pH 4.64), syrup from canned peaches (pH 3.97), and juice from canned pineapple (pH 3.65). When vegetative cells of B. coagulans CECT (Spanish Type Culture Collection) 12 were inoculated in tomato paste supplemented with 6 microg/ml AS-48 and stored at different temperatures, viable cell counts were reduced by approximately 2.37 (4 degrees C), 4.3 (22 degrees C) and 3.0 (37 degrees C) log units within 24 h storage. After 15-days storage, no viable cells were detected in any sample. Strain B. coagulans CECT 561 showed a poor survival in tomato paste, but surviving cells were also killed by AS-48. The bacteriocin was also very active against B. coagulans CECT 12 vegetative cells in juice from canned pineapple stored at 22 degrees C, and slightly less active in syrup from canned peaches. In food samples supplemented with 1.5% lactic acid, enterocin AS-48 (6 microg/ml) rapidly reduced viable counts of vegetative cells below detection limits within 24 h storage. Addition of glucose and sucrose (10% and 20%) significantly increased bacteriocin activity against vegetative cells of B. coagulans CECT 12. Enterocin AS-48 had no significant effect on B. coagulans CECT 12 spores. However, the combined application of AS-48 and heat (80-95 degrees C for 5 min) significantly increased the effect of thermal treatments on spores.

  20. Exoproteome and Secretome Derived Broad Spectrum Novel Drug and Vaccine Candidates in Vibrio cholerae Targeted by Piper betel Derived Compounds

    Science.gov (United States)

    Barh, Debmalya; Barve, Neha; Gupta, Krishnakant; Chandra, Sudha; Jain, Neha; Tiwari, Sandeep; Leon-Sicairos, Nidia; Canizalez-Roman, Adrian; Rodrigues dos Santos, Anderson; Hassan, Syed Shah; Almeida, Síntia; Thiago Jucá Ramos, Rommel; Augusto Carvalho de Abreu, Vinicius; Ribeiro Carneiro, Adriana; de Castro Soares, Siomar; Luiz de Paula Castro, Thiago; Miyoshi, Anderson; Silva, Artur; Kumar, Anil; Narayan Misra, Amarendra; Blum, Kenneth; Braverman, Eric R.; Azevedo, Vasco

    2013-01-01

    Vibrio cholerae is the causal organism of the cholera epidemic, which is mostly prevalent in developing and underdeveloped countries. However, incidences of cholera in developed countries are also alarming. Because of the emergence of new drug-resistant strains, even though several generic drugs and vaccines have been developed over time, Vibrio infections remain a global health problem that appeals for the development of novel drugs and vaccines against the pathogen. Here, applying comparative proteomic and reverse vaccinology approaches to the exoproteome and secretome of the pathogen, we have identified three candidate targets (ompU, uppP and yajC) for most of the pathogenic Vibrio strains. Two targets (uppP and yajC) are novel to Vibrio, and two targets (uppP and ompU) can be used to develop both drugs and vaccines (dual targets) against broad spectrum Vibrio serotypes. Using our novel computational approach, we have identified three peptide vaccine candidates that have high potential to induce both B- and T-cell-mediated immune responses from our identified two dual targets. These two targets were modeled and subjected to virtual screening against natural compounds derived from Piper betel. Seven compounds were identified first time from Piper betel to be highly effective to render the function of these targets to identify them as emerging potential drugs against Vibrio. Our preliminary validation suggests that these identified peptide vaccines and betel compounds are highly effective against Vibrio cholerae. Currently we are exhaustively validating these targets, candidate peptide vaccines, and betel derived lead compounds against a number of Vibrio species. PMID:23382822

  1. Exoproteome and secretome derived broad spectrum novel drug and vaccine candidates in Vibrio cholerae targeted by Piper betel derived compounds.

    Directory of Open Access Journals (Sweden)

    Debmalya Barh

    Full Text Available Vibrio cholerae is the causal organism of the cholera epidemic, which is mostly prevalent in developing and underdeveloped countries. However, incidences of cholera in developed countries are also alarming. Because of the emergence of new drug-resistant strains, even though several generic drugs and vaccines have been developed over time, Vibrio infections remain a global health problem that appeals for the development of novel drugs and vaccines against the pathogen. Here, applying comparative proteomic and reverse vaccinology approaches to the exoproteome and secretome of the pathogen, we have identified three candidate targets (ompU, uppP and yajC for most of the pathogenic Vibrio strains. Two targets (uppP and yajC are novel to Vibrio, and two targets (uppP and ompU can be used to develop both drugs and vaccines (dual targets against broad spectrum Vibrio serotypes. Using our novel computational approach, we have identified three peptide vaccine candidates that have high potential to induce both B- and T-cell-mediated immune responses from our identified two dual targets. These two targets were modeled and subjected to virtual screening against natural compounds derived from Piper betel. Seven compounds were identified first time from Piper betel to be highly effective to render the function of these targets to identify them as emerging potential drugs against Vibrio. Our preliminary validation suggests that these identified peptide vaccines and betel compounds are highly effective against Vibrio cholerae. Currently we are exhaustively validating these targets, candidate peptide vaccines, and betel derived lead compounds against a number of Vibrio species.

  2. Reversal of the Progression of Fatal Coronavirus Infection in Cats by a Broad-Spectrum Coronavirus Protease Inhibitor.

    Directory of Open Access Journals (Sweden)

    Yunjeong Kim

    2016-03-01

    Full Text Available Coronaviruses infect animals and humans causing a wide range of diseases. The diversity of coronaviruses in many mammalian species is contributed by relatively high mutation and recombination rates during replication. This dynamic nature of coronaviruses may facilitate cross-species transmission and shifts in tissue or cell tropism in a host, resulting in substantial change in virulence. Feline enteric coronavirus (FECV causes inapparent or mild enteritis in cats, but a highly fatal disease, called feline infectious peritonitis (FIP, can arise through mutation of FECV to FIP virus (FIPV. The pathogenesis of FIP is intimately associated with immune responses and involves depletion of T cells, features shared by some other coronaviruses like Severe Acute Respiratory Syndrome Coronavirus. The increasing risks of highly virulent coronavirus infections in humans or animals call for effective antiviral drugs, but no such measures are yet available. Previously, we have reported the inhibitors that target 3C-like protease (3CLpro with broad-spectrum activity against important human and animal coronaviruses. Here, we evaluated the therapeutic efficacy of our 3CLpro inhibitor in laboratory cats with FIP. Experimental FIP is 100% fatal once certain clinical and laboratory signs become apparent. We found that antiviral treatment led to full recovery of cats when treatment was started at a stage of disease that would be otherwise fatal if left untreated. Antiviral treatment was associated with a rapid improvement in fever, ascites, lymphopenia and gross signs of illness and cats returned to normal health within 20 days or less of treatment. Significant reduction in viral titers was also observed in cats. These results indicate that continuous virus replication is required for progression of immune-mediated inflammatory disease of FIP. These findings may provide important insights into devising therapeutic strategies and selection of antiviral compounds for

  3. Broad-spectrum sunscreens prevent the secretion of proinflammatory cytokines in human keratinocytes exposed to ultraviolet A and phototoxic lomefloxacin

    International Nuclear Information System (INIS)

    Reinhardt, P.; Cybulski, M.; Miller, S.M.; Ferrarotto, C.; Wilkins, R.; Deslauriers, Y.

    2006-01-01

    The combination of phototoxic drugs and ultraviolet (UV) radiation can trigger the release of proinflammatory cytokines. The present study measured the ability of sunscreens to prevent cytokine secretion in human keratinocytes following cotreatment of these cells with a known photoreactive drug and UVA. Keratinocytes were treated for 1 h with increasing concentrations of lomefloxacin (LOM) or norfloxacin (NOR), exposed to 15 J/cm 2 UVA, and incubated for 24 h. NOR, owing to the absence of a fluorine atom in position 8, was non-phototoxic and used as a negative control. Cell viability and the release of 3 cytokines were assessed, namely interleukin-1α (IL-1α), interleukin-6 (IL-6), and tumour necrosis factor-α (TNF-α). The measurement of these cytokines may be a useful tool for detecting photoreactive compounds. To measure their ability to prevent cytokine secretion, various sunscreens were inserted between the UVA source and the cells. Treatment with NOR, NOR plus UVA, or LOM had no effect on the cells. LOM plus UVA, however, had an effect on cell viability and on cytokine secretion. IL-1α levels increased with LOM concentration. The release of TNF-α and IL-6 followed the same pattern at lower concentrations of LOM but peaked at 15 μmol/L and decreased at higher concentrations. Sunscreens protected the cells from the effects of LOM plus UVA, as cell viability and levels of cytokines remained the same as in the control cells. In conclusion, the application of broad-spectrum sunscreen by individuals exposed to UVA radiation may prevent phototoxic reactions initiated by drugs such as LOM. (author)

  4. A Novel, Broad-Spectrum Inhibitor of Enterovirus Replication That Targets Host Cell Factor Phosphatidylinositol 4-Kinase IIIβ

    Science.gov (United States)

    van der Schaar, Hilde M.; Leyssen, Pieter; Thibaut, Hendrik J.; de Palma, Armando; van der Linden, Lonneke; Lanke, Kjerstin H. W.; Lacroix, Céline; Verbeken, Erik; Conrath, Katja; MacLeod, Angus M.; Mitchell, Dale R.; Palmer, Nicholas J.; van de Poël, Hervé; Andrews, Martin

    2013-01-01

    Despite their high clinical and socioeconomic impacts, there is currently no approved antiviral therapy for the prophylaxis or treatment of enterovirus infections. Here we report on a novel inhibitor of enterovirus replication, compound 1, 2-fluoro-4-(2-methyl-8-(3-(methylsulfonyl)benzylamino)imidazo[1,2-a]pyrazin-3-yl)phenol. This compound exhibited a broad spectrum of antiviral activity, as it inhibited all tested species of enteroviruses and rhinoviruses, with 50% effective concentrations ranging between 4 and 71 nM. After a lengthy resistance selection process, coxsackievirus mutants resistant to compound 1 were isolated that carried substitutions in their 3A protein. Remarkably, the same substitutions were recently shown to provide resistance to inhibitors of phosphatidylinositol 4-kinase IIIβ (PI4KIIIβ), a lipid kinase that is essential for enterovirus replication, suggesting that compound 1 may also target this host factor. Accordingly, compound 1 directly inhibited PI4KIIIβ in an in vitro kinase activity assay. Furthermore, the compound strongly reduced the PI 4-phosphate levels of the Golgi complex in cells. Rescue of coxsackievirus replication in the presence of compound 1 by a mutant PI4KIIIβ carrying a substitution in its ATP-binding pocket revealed that the compound directly binds the kinase at this site. Finally, we determined that an analogue of compound 1, 3-(3-fluoro-4-methoxyphenyl)-2-methyl-N-(pyridin-4-ylmethyl)imidazo[1,2-a]pyrazin-8-amine, is well tolerated in mice and has a dose-dependent protective activity in a coxsackievirus serotype B4-induced pancreatitis model. PMID:23896472

  5. Recent updates of marine antimicrobial peptides.

    Science.gov (United States)

    Semreen, Mohammad H; El-Gamal, Mohammed I; Abdin, Shifaa; Alkhazraji, Hajar; Kamal, Leena; Hammad, Saba; El-Awady, Faten; Waleed, Dima; Kourbaj, Layal

    2018-03-01

    Antimicrobial peptides are group of proteins showing broad-spectrum antimicrobial activity that have been known to be powerful agents against a variety of pathogens. This class of compounds contributed to solving the microbial resistance dilemma that limited the use of many potent antimicrobial agents. The marine environment is known to be one of the richest sources for antimicrobial peptides, yet this environment is not fully explored. Hence, the scientific research attention should be directed toward the marine ecosystem as enormous amount of useful discoveries could be brought to the forefront. In the current article, the marine antimicrobial peptides reported from mid 2012 to 2017 have been reviewed.

  6. Recent updates of marine antimicrobial peptides

    Directory of Open Access Journals (Sweden)

    Mohammad H. Semreen

    2018-03-01

    Full Text Available Antimicrobial peptides are group of proteins showing broad-spectrum antimicrobial activity that have been known to be powerful agents against a variety of pathogens. This class of compounds contributed to solving the microbial resistance dilemma that limited the use of many potent antimicrobial agents. The marine environment is known to be one of the richest sources for antimicrobial peptides, yet this environment is not fully explored. Hence, the scientific research attention should be directed toward the marine ecosystem as enormous amount of useful discoveries could be brought to the forefront. In the current article, the marine antimicrobial peptides reported from mid 2012 to 2017 have been reviewed.

  7. Antimicrobial Peptides with Differential Bacterial Binding Characteristics

    Science.gov (United States)

    2013-03-01

    organisms [5]. AMPs exhibit broad- spectrum antimicrobial activity against Gram-positive and Gram-negative bacteria, viruses, and fungi [6]. Hundreds of...polymerase chain reaction PE: PBS with 1mM EDTA PED: PBS with 1mM EDTA and 0.1µM dithiothreitol PEG: polyethylene glycol PL: pleurocidin RP-HPLC

  8. Antimicrobial Activity and Phytochemical Screening of Ficus ...

    African Journals Online (AJOL)

    Prelimlinary phytochemical screening of Ficus exasperata root bark showed that it contains saponin, alkaloids, cardiac glycoside and reducing sugar with no traces of tannin and anthraquinone. The results of the study provide scientific basis for developing a novel broad spectrum antimicrobial herbal formulation in future.

  9. In Vitro Evaluation of the Antimicrobial Effectiveness and Moisture Binding Properties of Wound Dressings

    Directory of Open Access Journals (Sweden)

    Teerapol Srichana

    2010-08-01

    Full Text Available A variety of silver-coated dressings and some impregnated with other chemicals are now available in the market; however, there have been few studies analyzing their comparative efficacies as antimicrobial agents. Moreover, their properties for retaining an appropriate level of moisture that is critical for effective wound healing have never been reported. Five commercially available silver-containing and chlorhexidine dressings, Urgotul SSD®, Bactigras®, Acticoat®, Askina Calgitrol Ag® and Aquacel Ag®, were tested to determine their comparative antimicrobial effectiveness in vitro against five common wound pathogens, namely methicillin-sensitive and -resistant Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. Mepitel®, a flexible polyamide net coated with soft silicone, was used as a control. The zones of inhibition and both the rapidity and the extent of killing of these pathogens were evaluated. All five antimicrobial dressings investigated exerted some bactericidal activity, particularly against E. coli. The spectrum and rapidity of action ranged widely for the different dressings. Acticoat® had a broad spectrum of action against both Gram-positive and -negative bacteria. Other dressings demonstrated a narrower range of bactericidal activities. Regarding the absorption and release of moisture, Askina Calgitrol Ag® absorbed and released the most moisture from the environment. Aquacel Ag® also exhibited good moisture absorption and moisture release, but to a lower degree. The other tested dressings absorbed or released very little moisture. Askina Calgitrol Ag® and Aquacel Ag® are good alternative dressings for treating wounds with high exudates and pus. An understanding of the characteristics of these dressings will be useful for utilizing them for specific requirements under specified conditions.

  10. Data-driven analysis of biomedical literature suggests broad-spectrum benevolence of culinary herbs and spices

    OpenAIRE

    K, Rakhi; Tuwani, Rudraksh; Mukherjee, Jagriti; Bagler, Ganesh

    2018-01-01

    Spices and herbs are key dietary ingredients used across cultures worldwide. Beyond their use as flavoring and coloring agents, the popularity of these aromatic plant products in culinary preparations has been attributed to their antimicrobial properties. Last few decades have witnessed an exponential growth of biomedical literature investigating the impact of spices and herbs on health, presenting an opportunity to mine for patterns from empirical evidence. Systematic investigation of empiri...

  11. Detection of a Mixed Infection in a Culture-Negative Brain Abscess by Broad-Spectrum Bacterial 16S rRNA Gene PCR ▿ †

    Science.gov (United States)

    Keller, Peter M.; Rampini, Silvana K.; Bloemberg, Guido V.

    2010-01-01

    We describe the identification of two bacterial pathogens from a culture-negative brain abscess by the use of broad-spectrum 16S rRNA gene PCR. Simultaneous detection of Fusobacterium nucleatum and Porphyromonas endodontalis was possible due to a 24-bp length difference of their partially amplified 16S rRNA genes, which allowed separation by high-resolution polyacrylamide gel electrophoresis. PMID:20392909

  12. A broad-spectrum sunscreen prevents cumulative damage from repeated exposure to sub-erythemal solar ultraviolet radiation representative of temperate latitudes.

    Science.gov (United States)

    Seité, S; Christiaens, F; Bredoux, C; Compan, D; Zucchi, H; Lombard, D; Fourtanier, A; Young, A R

    2010-02-01

    We have previously shown the detrimental effects of 19 sub-erythemal exposures to daily ultraviolet radiation (DUVR, which mimics non-extreme exposure conditions), delivered over 4 weeks to volunteers. This source had UVA (320-400 nm) to UVB (290-320 nm) irradiance ratio of 25, instead of that close to 10 that is typically the case with solar-simulated radiation (SSR) that represents summer global sunlight with a clear sky and quasi-zenith solar irradiance. Here, we report on an extension of this previous study, in which we evaluated the photoprotection afforded by a broad-spectrum daily-care product with a low-sun protection factor (SPF 8, UVA-PF 7 and 3* rated UVA protection). We assessed cellular and molecular markers of photodamage that are relevant to skin cancer and photoageing. This study shows that biological effects of repeated exposure to DUVR can be prevented by a broad-spectrum daily-care product and that the level of protection afforded varies with the studied endpoint. Efficient daily UVR protection, as provided by a broad-spectrum daily-care product, is necessary to prevent the 'silent' sub-erythemal cumulative effects of UVR from inadvertent sun exposure.

  13. Effect of healthcare associated infections and broad spectrum antibiotic use in newborn period on development of asthma, allergic rhinitis and atopic dermatitis in early childhood

    Directory of Open Access Journals (Sweden)

    Hacer Yapicioglu Yildizdas

    2017-03-01

    Full Text Available Purpose: The iam of this study was to investigate the effect of healthcare associated infections (HAIs and broad spectrum antibiotic use in newborn period on asthma, allergic rhinitis and atopic dermatitis. Material and Methods: Seventy three children treated for HAIs in newborn period in Neonatal Intesive Care Unitin a 6 years period, and their 41 siblings who were healthy in newborn period were included in the study. Parents answered a detailed questionnaire, children were examined and complete blood count, serum total Ig E and specific Ig E levels were studied. Results: Ventilator associated pneumonia was observed in 32 (45.2%, blood stream infection in 28 (38.4% and clinic sepsis in 12 (16.4% of 73 children with HAIs. Asthma was significantly higher in HAIs group compared to sibling group (32.9% vs. 4.9, whereas there was no significant difference in allergic rhinitis (4.1% vs.2.4% and atopic dermatitis (6.8% vs. 0% among groups. When non-allergic 85 subjects and allergic 29 children compared, children who had been hospitalised and treated with broad-spectrum antibiotics in newborn period were almost 11.5 times as likely to have an allergic disease. Conclusion: Asthma was significantly higher in HAI group, and allergic disease risk seems to increase in children treated with broad-spectrum antibiotics for HAIs in newborn period. [Cukurova Med J 2017; 42(1.000: 132-139

  14. Efficacy of a novel antimicrobial peptide against periodontal pathogens in both planktonic and polymicrobial biofilm states.

    Science.gov (United States)

    Wang, Hong-Yan; Cheng, Jya-Wei; Yu, Hui-Yuan; Lin, Li; Chih, Ya-Han; Pan, Ya-Ping

    2015-10-01

    Streptococcus gordonii, Fusobacterium nucleatum and Porphyromonas gingivalis represent the early, middle and late colonizers of the bacterial accretion in dental plaque biofilms. These sessile communities constitute a protected mode of growth that promotes survival in a hostile environment. This study describes a novel and unrecognized role for a synthetic cationic antimicrobial peptide, Nal-P-113, which inhibits and kills periodontal bacteria in planktonic state, inhibits the formation of biofilms and eradicates polymicrobial biofilms. Nal-P-113 is also stable in saliva, serum and saline solution. At a concentration less than 320 μg/mL which is harmless to normal oral cells, Nal-P-113 can kill bacteria in planktonic state. At a concentration of antimicrobial peptide Nal-P-113 (1280 μg/mL) which only causes slight damages to normal oral cells is needed to kill bacteria in biofilm state. It is worth mentioning that this concentration of Nal-P-113 is harmless to rat oral mucosa compared to chlorhexidine. The mechanism of Nal-P-113 inhibiting and killing periodontal bacteria might rely on the abilities to permeabilize and/or to form pores within the cytoplasmic membranes, thus causes the death of bacteria. Here, we provided a novel and stable antimicrobial peptide with very low mammalian cytotoxicity, which can inhibit and kill periodontal bacteria in both planktonic and polymicrobial biofilm states. Nal-P-113 is a potent antimicrobial peptide with strong antimicrobial ability, improved deficiency compared with other antibacterial peptides, and remains stable in phosphate buffered saline, saliva, brain-heart infusion medium and bovine calf serum. Nal-P-113 exhibits a broad spectrum of bacteriocidal activity with excellent eradicating capability on oral pathogens and the respective biofilms. In this study, we used propidium iodide staining, scanning electron microscopy and transmission electron microscopy to confirm that Nal-P-113 can perforate plasmalemma thereby

  15. Treatment Modalities and Antimicrobial Stewardship Initiatives in the Management of Intra-Abdominal Infections

    Directory of Open Access Journals (Sweden)

    Charles Hoffmann

    2016-02-01

    Full Text Available Antimicrobial stewardship programs (ASPs focus on improving the utilization of broad spectrum antibiotics to decrease the incidence of multidrug-resistant Gram positive and Gram negative pathogens. Hospital admission for both medical and surgical intra-abdominal infections (IAIs commonly results in the empiric use of broad spectrum antibiotics such as fluoroquinolones, beta-lactam beta-lactamase inhibitors, and carbapenems that can select for resistant organisms. This review will discuss the management of uncomplicated and complicated IAIs as well as highlight stewardship initiatives focusing on the proper use of broad spectrum antibiotics.

  16. Cytokine expression in human osteoblasts after antiseptic treatment: a comparative study between polyhexanide and chlorhexidine.

    Science.gov (United States)

    Röhner, Eric; Hoff, Paula; Gaber, Timo; Lang, Annemarie; Vörös, Pauline; Buttgereit, Frank; Perka, Carsten; Windisch, Christoph; Matziolis, Georg

    2015-02-01

    Chlorhexidine and polyhexanide are frequently used antiseptics in clinical practice and have a broad antimicrobial range. Both antiseptics are helpful medical agents for septic wound treatment with a high potential for defeating joint infections. Their effect on human osteoblasts has, so far, not been sufficiently evaluated. The aim of this study was to investigate the activating potential of polyhexanide and chlorhexidine on inflammatory cytokines/chemokines in human osteoblasts in vitro. Human osteoblasts were isolated and cultivated in vitro and then treated separately with 0.1% and 2% chlorhexidine and 0.04% polyhexanide as commonly applied concentrations in clinical practice. Detection of cell structure and cell morphology was performed by light microscopic inspection. Cytokine and chemokine secretion was determined by using a multiplex suspension array. Cell shrinking, defective cell membrane, and the loss of cell adhesion indicated cell damage of human osteoblasts after treatment with both antiseptics was evaluated by using light microscopy. Polyhexanide, but not chlorhexidine, caused human osteoblasts to secrete various interleukins (1β, 6, and 7), interferon γ, tumor necrosis factor α, vascular endothelial growth factor, eotaxin, fibroblast growth factor basic, and granulocyte macrophage colony-stimulating factor as quantified by multiplex suspension array. Both antiseptics induced morphological cell damage at an optimum exposure between 1 and 10 min. But only polyhexanide mediated a pronounced secretion of inflammatory cytokines and chemokines in human osteoblasts. Therefore, we recommend a preferred usage of chlorhexidine in septic surgery to avoid the induction of an inflammatory reaction.

  17. The synthetic human beta-defensin-3 C15 peptide exhibits antimicrobial activity against Streptococcus mutans, both alone and in combination with dental disinfectants.

    Science.gov (United States)

    Ahn, Ki Bum; Kim, A Reum; Kum, Kee-Yeon; Yun, Cheol-Heui; Han, Seung Hyun

    2017-10-01

    Streptococcus mutans is a major etiologic agent of human dental caries that forms biofilms on hard tissues in the human oral cavity, such as tooth and dentinal surfaces. Human β-defensin-3 (HBD3) is a 45-amino-acid natural antimicrobial peptide that has broad spectrum antimicrobial activity against bacteria and fungi. A synthetic peptide consisting of the C-terminal 15 amino acids of HBD3 (HBD3-C15) was recently shown to be sufficient for its antimicrobial activity. Thus, clinical applications of this peptide have garnered attention. In this study, we investigated whether HBD3-C15 inhibits the growth of the representative cariogenic pathogen Streptococcus mutans and its biofilm formation. HBD3-C15 inhibited bacterial growth, exhibited bactericidal activity, and attenuated bacterial biofilm formation in a dose-dependent manner. HBD3-C15 potentiated the bactericidal and anti-biofilm activity of calcium hydroxide (CH) and chlorhexidine digluconate (CHX), which are representative disinfectants used in dental clinics, against S. mutans. Moreover, HBD3-C15 showed antimicrobial activity by inhibiting biofilm formation by S. mutans and other dentinophilic bacteria such as Enterococcus faecalis and Streptococcus gordonii, which are associated with dental caries and endodontic infection, on human dentin slices. These effects were observed for HBD3-C15 alone and for HBD3-C15 in combination with CH or CHX. Therefore, we suggest that HBD3-C15 is a potential alternative or additive disinfectant that can be used for the treatment of oral infectious diseases, including dental caries and endodontic infections.

  18. Spectrum of antimicrobial activity associated with ionic colloidal silver.

    Science.gov (United States)

    Morrill, Kira; May, Kathleen; Leek, Daniel; Langland, Nicole; Jeane, La Deana; Ventura, Jose; Skubisz, Corey; Scherer, Sean; Lopez, Eric; Crocker, Ephraim; Peters, Rachel; Oertle, John; Nguyen, Krystine; Just, Scott; Orian, Michael; Humphrey, Meaghan; Payne, David; Jacobs, Bertram; Waters, Robert; Langland, Jeffrey

    2013-03-01

    Silver has historically and extensively been used as a broad-spectrum antimicrobial agent. However, the Food and Drug Administration currently does not recognize colloidal silver as a safe and effective antimicrobial agent. The goal of this study was to further evaluate the antimicrobial efficacy of colloidal silver. Several strains of bacteria, fungi, and viruses were grown under multicycle growth conditions in the presence or absence of ionic colloidal silver in order to assess the antimicrobial activity. For bacteria grown under aerobic or anaerobic conditions, significant growth inhibition was observed, although multiple treatments were typically required. For fungal cultures, the effects of ionic colloidal silver varied significantly between different genera. No viral growth inhibition was observed with any strains tested. The study data support ionic colloidal silver as a broad-spectrum antimicrobial agent against aerobic and anaerobic bacteria, while having a more limited and specific spectrum of activity against fungi.

  19. Evaluation of Carbohydrate-Derived Fulvic Acid (CHD-FA) as a Topical Broad-Spectrum Antimicrobial for Drug-Resistant Wound Infections

    Science.gov (United States)

    2016-10-01

    the newly formulated CHD-FA-Zn. Our initial results demonstrated that CHD-FA-Zn reduced microbial burdens of susceptible and drug- resistant planktonic...wound-associated drug resistant bacteria and fungi. Rat models of wound infection (open, and burn model) will be established with healthy animals ...Establish MIC90s for CHD-FA with clinical isolates of major drug resistant pathogens Assess CHD-FA in animal models of wound infection for major

  20. Structural and biophysical characterization of an antimicrobial peptide chimera comprised of lactoferricin and lactoferrampin

    NARCIS (Netherlands)

    Haney, E.F.; Nazmi, K.; Bolscher, J.G.M.; Vogel, H.J.

    2012-01-01

    Lactoferricin and lactoferrampin are two antimicrobial peptides found in the N-terminal lobe of bovine lactoferrin with broad spectrum antimicrobial activity against a range of Gram-positive and Gram-negative bacteria as well as Candida albicans. A heterodimer comprised of lactoferrampin joined to a

  1. Does chlorhexidine prevent dry socket?

    Science.gov (United States)

    Richards, Derek

    2012-01-01

    The BBO (Bibliografia Brasileira de Odontologia), Biomed Central, Cochrane Library, Directory of Open Access Journals, LILACS, Open-J-Gate, OpenSIGLE, PubMed, Sabinet and Science-Direct databases were searched. Articles were selected for review from the search results on the basis of their compliance with the broad inclusion criteria: relevant to the review question; and prospective two-arm (or more) clinical study. The primary outcome measure was the incidence of AO reported at the patient level. Two reviewers (VY and SM) independently extracted data and assessed the quality of the accepted articles. Individual dichotomous datasets for the control and test group were extracted from each article. Where possible, missing data were calculated from information given in the text or tables. In addition, authors were contacted in order to obtain missing information. Datasets were assessed for their clinical and methodological heterogeneity following Cochrane guidelines. Meta-analysis was conducted with homogeneous datasets. Publication bias was assessed by use of a funnel plot and Egger's regression. Ten randomised trials were included; almost all involved the removal of third molars. Only two of six identified application protocols (single application of chlorhexidine 0.2% gel or multiple application of 0.12% rinse versus placebo) were found to significantly decrease the incidence of AO. Within the limitations of this review, only two of six identified application protocols were found to significantly decrease the incidence of AO. The evidence for both protocols is weak and may be challenged on the grounds of high risk of selection, detection/performance and attrition bias. This systematic review could not identify sufficient evidence supporting the use of chlorhexidine for the prevention of AO. Chlorhexidine seems not to cause any significantly higher adverse reactions than placebo. Future high-quality randomised control trials are needed to provide conclusive evidence

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

    Science.gov (United States)

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

    1993-01-01

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

  3. Tricyclic GyrB/ParE (TriBE inhibitors: a new class of broad-spectrum dual-targeting antibacterial agents.

    Directory of Open Access Journals (Sweden)

    Leslie W Tari

    Full Text Available Increasing resistance to every major class of antibiotics and a dearth of novel classes of antibacterial agents in development pipelines has created a dwindling reservoir of treatment options for serious bacterial infections. The bacterial type IIA topoisomerases, DNA gyrase and topoisomerase IV, are validated antibacterial drug targets with multiple prospective drug binding sites, including the catalytic site targeted by the fluoroquinolone antibiotics. However, growing resistance to fluoroquinolones, frequently mediated by mutations in the drug-binding site, is increasingly limiting the utility of this antibiotic class, prompting the search for other inhibitor classes that target different sites on the topoisomerase complexes. The highly conserved ATP-binding subunits of DNA gyrase (GyrB and topoisomerase IV (ParE have long been recognized as excellent candidates for the development of dual-targeting antibacterial agents with broad-spectrum potential. However, to date, no natural product or small molecule inhibitors targeting these sites have succeeded in the clinic, and no inhibitors of these enzymes have yet been reported with broad-spectrum antibacterial activity encompassing the majority of Gram-negative pathogens. Using structure-based drug design (SBDD, we have created a novel dual-targeting pyrimidoindole inhibitor series with exquisite potency against GyrB and ParE enzymes from a broad range of clinically important pathogens. Inhibitors from this series demonstrate potent, broad-spectrum antibacterial activity against Gram-positive and Gram-negative pathogens of clinical importance, including fluoroquinolone resistant and multidrug resistant strains. Lead compounds have been discovered with clinical potential; they are well tolerated in animals, and efficacious in Gram-negative infection models.

  4. Targeting N-Glycan Cryptic Sugar Moieties for Broad-Spectrum Virus Neutralization: Progress in Identifying Conserved Molecular Targets in Viruses of Distinct Phylogenetic Origins

    Directory of Open Access Journals (Sweden)

    Denong Wang

    2015-03-01

    Full Text Available Identifying molecular targets for eliciting broadly virus-neutralizing antibodies is one of the key steps toward development of vaccines against emerging viral pathogens. Owing to genomic and somatic diversities among viral species, identifying protein targets for broad-spectrum virus neutralization is highly challenging even for the same virus, such as HIV-1. However, viruses rely on host glycosylation machineries to synthesize and express glycans and, thereby, may display common carbohydrate moieties. Thus, exploring glycan-binding profiles of broad-spectrum virus-neutralizing agents may provide key information to uncover the carbohydrate-based virus-neutralizing epitopes. In this study, we characterized two broadly HIV-neutralizing agents, human monoclonal antibody 2G12 and Galanthus nivalis lectin (GNA, for their viral targeting activities. Although these agents were known to be specific for oligomannosyl antigens, they differ strikingly in virus-binding activities. The former is HIV-1 specific; the latter is broadly reactive and is able to neutralize viruses of distinct phylogenetic origins, such as HIV-1, severe acute respiratory syndrome coronavirus (SARS-CoV, and human cytomegalovirus (HCMV. In carbohydrate microarray analyses, we explored the molecular basis underlying the striking differences in the spectrum of anti-virus activities of the two probes. Unlike 2G12, which is strictly specific for the high-density Man9GlcNAc2Asn (Man9-clusters, GNA recognizes a number of N-glycan cryptic sugar moieties. These include not only the known oligomannosyl antigens but also previously unrecognized tri-antennary or multi-valent GlcNAc-terminating N-glycan epitopes (Tri/m-Gn. These findings highlight the potential of N-glycan cryptic sugar moieties as conserved targets for broad-spectrum virus neutralization and suggest the GNA-model of glycan-binding warrants focused investigation.

  5. MgO Nanoparticle-Catalyzed Synthesis and Broad-Spectrum Antibacterial Activity of Imidazolidine- and Tetrahydropyrimidine-2-Thione Derivatives.

    Science.gov (United States)

    Beyzaei, Hamid; Kooshki, Somaye; Aryan, Reza; Zahedi, Mohammad Mehdi; Samzadeh-Kermani, Alireza; Ghasemi, Behzad; Moghaddam-Manesh, Mohammadreza

    2018-01-01

    The biological properties of imidazolidine- and tetrahydropyrimidine-2-thione derivatives such as antiviral, antitumor, anti-inflammatory, and analgesic activities increase the demand for mild and efficient synthetic routes. In this regard, methods such as reaction of diaminoalkanes with carbon disulfide have been developed. However, this method usually suffers from relatively long reaction times, using excess reagents, vigorous reaction conditions, and emission of pernicious hydrogen sulfide gas. In this project, MgO nanoparticle was used as an efficient, non-toxic, recyclable, and economic catalyst to synthesize cyclic five- or six-membered thioureas 3a-h via reaction of 1:1 molar ratios of 1,2- or 1,3-diaminoalkanes 1a-h and carbon disulfide in ethanol at ambient temperature. More interestingly, no hydrogen sulfide emission was detected during the reaction progress. The in vitro antimicrobial properties of synthesized compounds were investigated against 14 different Gram-positive and Gram-negative pathogenic bacteria according to CLSI (Clinical and Laboratory Standards Institute) broth microdilution and disk diffusion methods. The results were compared to those of penicillin, gentamicin, and ceftriaxone, and reported as inhibition zone diameter (IZD), the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC) values. The best inhibitory effects were observed with imidazolidine-2-thiones 3c and 3d. They were effective against 14 and 11 pathogens, respectively. The structure-activity relationships of the prepared heterocyclic compounds were also studied.

  6. Root Canal Retreatment menggunakan Kombinasi Kalsium Hidroksida dan Chlorhexidine sebagai Medikamen Intra Kanal Insisivus Sentral Kiri Maksila

    Directory of Open Access Journals (Sweden)

    Andina Novita Sari

    2014-12-01

    retreatment dengan cleaning dan shaping ulang yang baik dengan menggunakan medikasi intrakanal berupa kombinasi kalsium hidroksida dan chlorhexidine 2% diharapkan mempunyai efek antimikroba yang sinergis untuk mencapai kesuksesan root canal retreatment.   Root Canal Retreatment Using Calcium Hydroxide as Intra Canal Medicament On The Maxillary Left Incisor. Enterococcus faecalis bacteria is most abundant in the root canal infection treated endodontically. Chlorhexidine has a broad antibacterial spectrum and has been used as an endodontic irrigant and intracanal medication. Chlorhexidine has a bactericidal and fungicidal effect as chlorhexidine absorbed into the bacterial cell surface and cause damage to the integrity of the cell membrane. Calcium hydroxide is a biocompatible, antimicrobial agents with high pH effects and stimulates hard tissue formation. A mixture of calcium hydroxide and chlorhexidine is used to control bacteria Enterococcus faecalis alternative. The purpose of this case report is to report on the success of root canal treatment in the left maxillary central incisor with acute periapical periodontitis using a combination of calcium hydroxide and chlorhexidine as intracanal A 24 years old female patient presents with left upper central incisor tooth ache since 4 years ago. The tooth was hurt to percussion, but normal to pulpation as well as the mobility. The tooth has a history of previous trauma and broken 6 years ago and has performed endodontic treatment. Radiographic examination showed obturation teeth 21 are not hermetic with periapical radiolucency in diffuse boundaries, widening of the periodontal ligament and the dissolution of the lamina dura. Root canal re-treatment using a combination of calcium hydroxide and chlorhexidine as intracanal medicaments were performed. In conclussion, the root canal cleaning and shaping retreatment can be performed using a combination of calcium hydroxide and chlorhexidine as intracanal

  7. Broad spectrum antibacterial and antifungal polymeric paint materials: synthesis, structure-activity relationship, and membrane-active mode of action.

    Science.gov (United States)

    Hoque, Jiaul; Akkapeddi, Padma; Yadav, Vikas; Manjunath, Goutham B; Uppu, Divakara S S M; Konai, Mohini M; Yarlagadda, Venkateswarlu; Sanyal, Kaustuv; Haldar, Jayanta

    2015-01-28

    Microbial attachment and subsequent colonization onto surfaces lead to the spread of deadly community-acquired and hospital-acquired (nosocomial) infections. Noncovalent immobilization of water insoluble and organo-soluble cationic polymers onto a surface is a facile approach to prevent microbial contamination. In the present study, we described the synthesis of water insoluble and organo-soluble polymeric materials and demonstrated their structure-activity relationship against various human pathogenic bacteria including drug-resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and beta lactam-resistant Klebsiella pneumoniae as well as pathogenic fungi such as Candida spp. and Cryptococcus spp. The polymer coated surfaces completely inactivated both bacteria and fungi upon contact (5 log reduction with respect to control). Linear polymers were more active and found to have a higher killing rate than the branched polymers. The polymer coated surfaces also exhibited significant activity in various complex mammalian fluids such as serum, plasma, and blood and showed negligible hemolysis at an amount much higher than minimum inhibitory amounts (MIAs). These polymers were found to have excellent compatibility with other medically relevant polymers (polylactic acid, PLA) and commercial paint. The cationic hydrophobic polymer coatings disrupted the lipid membrane of both bacteria and fungi and thus showed a membrane-active mode of action. Further, bacteria did not develop resistance against these membrane-active polymers in sharp contrast to conventional antibiotics and lipopeptides, thus the polymers hold great promise to be used as coating materials for developing permanent antimicrobial paint.

  8. Broad-spectrum inhibition of HIV-1 by a monoclonal antibody directed against a gp120-induced epitope of CD4.

    Science.gov (United States)

    Burastero, Samuele E; Frigerio, Barbara; Lopalco, Lucia; Sironi, Francesca; Breda, Daniela; Longhi, Renato; Scarlatti, Gabriella; Canevari, Silvana; Figini, Mariangela; Lusso, Paolo

    2011-01-01

    To penetrate susceptible cells, HIV-1 sequentially interacts with two highly conserved cellular receptors, CD4 and a chemokine receptor like CCR5 or CXCR4. Monoclonal antibodies (MAbs) directed against such receptors are currently under clinical investigation as potential preventive or therapeutic agents. We immunized Balb/c mice with molecular complexes of the native, trimeric HIV-1 envelope (Env) bound to a soluble form of the human CD4 receptor. Sera from immunized mice were found to contain gp120-CD4 complex-enhanced antibodies and showed broad-spectrum HIV-1-inhibitory activity. A proportion of MAbs derived from these mice preferentially recognized complex-enhanced epitopes. In particular, a CD4-specific MAb designated DB81 (IgG1Κ) was found to preferentially bind to a complex-enhanced epitope on the D2 domain of human CD4. MAb DB81 also recognized chimpanzee CD4, but not baboon or macaque CD4, which exhibit sequence divergence in the D2 domain. Functionally, MAb DB81 displayed broad HIV-1-inhibitory activity, but it did not exert suppressive effects on T-cell activation in vitro. The variable regions of the heavy and light chains of MAb DB81 were sequenced. Due to its broad-spectrum anti-HIV-1 activity and lack of immunosuppressive effects, a humanized derivative of MAb DB81 could provide a useful complement to current preventive or therapeutic strategies against HIV-1.

  9. Broad-spectrum inhibition of HIV-1 by a monoclonal antibody directed against a gp120-induced epitope of CD4.

    Directory of Open Access Journals (Sweden)

    Samuele E Burastero

    Full Text Available To penetrate susceptible cells, HIV-1 sequentially interacts with two highly conserved cellular receptors, CD4 and a chemokine receptor like CCR5 or CXCR4. Monoclonal antibodies (MAbs directed against such receptors are currently under clinical investigation as potential preventive or therapeutic agents. We immunized Balb/c mice with molecular complexes of the native, trimeric HIV-1 envelope (Env bound to a soluble form of the human CD4 receptor. Sera from immunized mice were found to contain gp120-CD4 complex-enhanced antibodies and showed broad-spectrum HIV-1-inhibitory activity. A proportion of MAbs derived from these mice preferentially recognized complex-enhanced epitopes. In particular, a CD4-specific MAb designated DB81 (IgG1Κ was found to preferentially bind to a complex-enhanced epitope on the D2 domain of human CD4. MAb DB81 also recognized chimpanzee CD4, but not baboon or macaque CD4, which exhibit sequence divergence in the D2 domain. Functionally, MAb DB81 displayed broad HIV-1-inhibitory activity, but it did not exert suppressive effects on T-cell activation in vitro. The variable regions of the heavy and light chains of MAb DB81 were sequenced. Due to its broad-spectrum anti-HIV-1 activity and lack of immunosuppressive effects, a humanized derivative of MAb DB81 could provide a useful complement to current preventive or therapeutic strategies against HIV-1.

  10. Discovery of dapivirine, a nonnucleoside HIV-1 reverse transcriptase inhibitor, as a broad-spectrum antiviral against both influenza A and B viruses.

    Science.gov (United States)

    Hu, Yanmei; Zhang, Jiantao; Musharrafieh, Rami Ghassan; Ma, Chunlong; Hau, Raymond; Wang, Jun

    2017-09-01

    The emergence of multidrug-resistant influenza viruses poses a persistent threat to public health. The current prophylaxis and therapeutic interventions for influenza virus infection have limited efficacy due to the continuous antigenic drift and antigenic shift of influenza viruses. As part of our ongoing effort to develop the next generation of influenza antivirals with broad-spectrum antiviral activity and a high genetic barrier to drug resistance, in this study we report the discovery of dapivirine, an FDA-approved HIV nonnucleoside reverse transcriptase inhibitor, as a broad-spectrum antiviral against multiple strains of influenza A and B viruses with low micromolar efficacy. Mechanistic studies revealed that dapivirine inhibits the nuclear entry of viral ribonucleoproteins at the early stage of viral replication. As a result, viral RNA and protein synthesis were inhibited. Furthermore, dapivirine has a high in vitro genetic barrier to drug resistance, and its antiviral activity is synergistic with oseltamivir carboxylate. In summary, the in vitro antiviral results of dapivirine suggest it is a promising candidate for the development of the next generation of dual influenza and HIV antivirals. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Biogenic synthesis of Zinc oxide nanostructures from Nigella sativa seed: Prospective role as food packaging material inhibiting broad-spectrum quorum sensing and biofilm.

    Science.gov (United States)

    Al-Shabib, Nasser A; Husain, Fohad Mabood; Ahmed, Faheem; Khan, Rais Ahmad; Ahmad, Iqbal; Alsharaeh, Edreese; Khan, Mohd Shahnawaz; Hussain, Afzal; Rehman, Md Tabish; Yusuf, Mohammad; Hassan, Iftekhar; Khan, Javed Masood; Ashraf, Ghulam Md; Alsalme, Ali Mohammed; Al-Ajmi, Mohamed F; Tarasov, Vadim V; Aliev, Gjumrakch

    2016-12-05

    Bacterial spoilage of food products is regulated by density dependent communication system called quorum sensing (QS). QS control biofilm formation in numerous food pathogens and Biofilms formed on food surfaces act as carriers of bacterial contamination leading to spoilage of food and health hazards. Agents inhibiting or interfering with bacterial QS and biofilm are gaining importance as a novel class of next-generation food preservatives/packaging material. In the present study, Zinc nanostructures were synthesised using Nigella sativa seed extract (NS-ZnNPs). Synthesized nanostructures were characterized hexagonal wurtzite structure of size ~24 nm by UV-visible, XRD, FTIR and TEM. NS-ZnNPs demonstrated broad-spectrum QS inhibition in C. violaceum and P. aeruginosa biosensor strains. Synthesized nanostructures inhibited QS regulated functions of C. violaceum CVO26 (violacein) and elastase, protease, pyocyanin and alginate production in PAO1 significantly. NS-ZnNPs at sub-inhibitory concentrations inhibited the biofilm formation of four-food pathogens viz. C. violaceum 12472, PAO1, L. monocytogenes, E. coli. Moreover, NS-ZnNPs was found effective in inhibiting pre-formed mature biofilms of the four pathogens. Therefore, the broad-spectrum inhibition of QS and biofilm by biogenic Zinc oxide nanoparticles and it is envisaged that these nontoxic bioactive nanostructures can be used as food packaging material and/or as food preservative.

  12. Spectrum of microbial growth and antimicrobial usage in an ...

    African Journals Online (AJOL)

    Intensive-care units (ICUs) are a source of multidrug-resistant organisms, owing to the indiscriminate usage of broad-spectrum antimicrobial drugs. In such ... Staphylococcus aureus was the most common isolate from blood and central venous lines, and Pseudomonas aeruginosa from tracheal aspirates and wound swabs.

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

    Science.gov (United States)

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

    2017-06-09

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

  14. Third generation cephalosporin resistant Enterobacteriaceae and multidrug resistant gram-negative bacteria causing bacteremia in febrile neutropenia adult cancer patients in Lebanon, broad spectrum antibiotics use as a major risk factor, and correlation with poor prognosis

    Directory of Open Access Journals (Sweden)

    Rima eMoghnieh

    2015-02-01

    Full Text Available Bacteremia remains a major cause of life-threatening complications in patients receiving anticancer chemotherapy. The spectrum and susceptibility profiles of causative microorganisms differ with time and place. Data from Lebanon are scarce. We aim at evaluating the epidemiology of bacteremia in cancer patients in a university hospital in Lebanon, emphasizing antibiotic resistance and risk factors of multi-drug resistant organism (MDRO-associated bacteremia.This is a retrospective study of 75 episodes of bacteremia occurring in febrile neutropenic patients admitted to the hematology-oncology unit at Makassed General Hospital, Lebanon, from October 2009-January 2012.It corresponds to epidemiological data on bacteremia episodes in febrile neutropenic cancer patients including antimicrobial resistance and identification of risk factors associated with third generation cephalosporin resistance (3GCR and MDRO-associated bacteremia. Out of 75 bacteremias, 42.7% were gram-positive (GP, and 57.3% were gram-negative (GN. GP bacteremias were mostly due to methicillin-resistant coagulase negative staphylococci (28% of total bacteremias and 66% of GP bacteremias. Among the GN bacteremias, Escherichia coli (22.7% of total, 39.5% of GN organisms and Klebsiellapneumoniae(13.3% of total, 23.3% of GN organisms were the most important causative agents. GN bacteremia due to 3GC sensitive (3GCS bacteria represented 28% of total bacteremias, while 29% were due to 3GCR bacteria and 9% were due to carbapenem-resistant organisms. There was a significant correlation between bacteremia with MDRO and subsequent intubation, sepsis and mortality. Among potential risk factors, only broad spectrum antibiotic intake >4 days before bacteremia was found to be statistically significant for acquisition of 3GCR bacteria. Using carbapenems or piperacillin/ tazobactam>4 days before bacteremia was significantly associated with the emergence of MDRO (p value<0.05.

  15. Sealing ability of mineral trioxide aggregate (MTA) combined with distilled water, chlorhexidine, and doxycycline.

    Science.gov (United States)

    Arruda, Roberta A A; Cunha, Rodrigo S; Miguita, Kenner B; Silveira, Cláudia F M; De Martin, Alexandre S; Pinheiro, Sérgio L; Rocha, Daniel G P; Bueno, Carlos E S

    2012-09-01

    The aim of this study was to evaluate the sealing ability of mineral trioxide aggregate (MTA Bio) combined with different mixing agents (distilled water, chlorhexidine, doxycycline), used as an apical root-end filling material. Forty-two extracted human teeth were divided into three groups (n = 12); six teeth were used as controls. Root-ends were resected at 90 degrees, 3 mm from the apex. Root-end cavities were prepared using ultrasonic tips and filled with MTA Bio plus distilled water, 2% chlorhexidine solution, or 10% doxycycline solution. Apical sealing was assessed by microleakage of 50% silver nitrate solution. Roots were longitudinally sectioned in a buccolingual plane and analyzed using an operating microscope (20× magnification). Depth of dye leakage into the dentinal walls was measured in millimeters. Results were analyzed using ANOVA and Tukey's test (P = 0.05). MTA Bio plus distilled water showed significantly higher mean leakage results (1.06 mm) when compared with MTA Bio plus doxycycline (0.61 mm), and higher, although not significant, results when compared with MTA Bio plus chlorhexidine (0.79 mm). In conclusion, replacing distilled water with two biologically active mixing agents (doxycycline and chlorhexidine) did not alter the sealing properties of MTABio. The antimicrobial properties of these combinations should be further investigated.

  16. Effect of fluoride and chlorhexidine digluconate mouthrinses on plaque biofilms

    DEFF Research Database (Denmark)

    Rabe, Per; Twetman, Svante; Kinnby, Bertil

    2015-01-01

    OBJECTIVE: To develop a model in which to investigate the architecture of plaque biofilms formed on enamel surfaces in vivo and to compare the effects of anti-microbial agents of relevance for caries on biofilm vitality. Materials and Methodology : Enamel discs mounted on healing abutments...... in the pre-molar region were worn by three subjects for 7 days. Control discs were removed before subjects rinsed with 0.1% chlorhexidine digluconate (CHX) or 0.2% sodium fluoride (NaF) for 1 minute. Biofilms were stained with Baclight Live/Dead and z-stacks of images created using confocal scanning laser...... micoscopy. The levels of vital and dead/damaged bacteria in the biofilms, assessed as the proportion of green and red pixels respectively, were analysed using ImageTrak(®) software. Results : The subjects showed individual differences in biofilm architecture. The thickness of the biofilms varied from 28...

  17. Novel, broad-spectrum anticonvulsants containing a sulfamide group: advancement of N-((benzo[b]thien-3-yl)methyl)sulfamide (JNJ-26990990) into human clinical studies.

    Science.gov (United States)

    Parker, Michael H; Smith-Swintosky, Virginia L; McComsey, David F; Huang, Yifang; Brenneman, Douglas; Klein, Brian; Malatynska, Ewa; White, H Steve; Milewski, Michael E; Herb, Mark; Finley, Michael F A; Liu, Yi; Lubin, Mary Lou; Qin, Ning; Iannucci, Robert; Leclercq, Laurent; Cuyckens, Filip; Reitz, Allen B; Maryanoff, Bruce E

    2009-12-10

    In seeking broad-spectrum anticonvulsants to treat epilepsy and other neurological disorders, we synthesized and tested a group of sulfamide derivatives (4a-k, 5), which led to the clinical development of 4a (JNJ-26990990). This compound exhibited excellent anticonvulsant activity in rodents against audiogenic, electrically induced, and chemically induced seizures, with very weak inhibition of human carbonic anhydrase-II (IC(50) = 110 microM). The pharmacological profile for 4a supports its potential in the treatment of multiple forms of epilepsy, including pharmacoresistant variants. Mechanistically, 4a inhibited voltage-gated Na(+) channels and N-type Ca(2+) channels but was not effective as a K(+) channel opener. The pharmacokinetics and metabolic properties of 4a are discussed.

  18. Bio-Inspired Wide-Angle Broad-Spectrum Cylindrical Lens Based on Reflections from Micro-Mirror Array on a Cylindrical Elastomeric Membrane

    Directory of Open Access Journals (Sweden)

    Chi-Chieh Huang

    2014-06-01

    Full Text Available We present a wide-angle, broad-spectrum cylindrical lens based on reflections from an array of three-dimensional, high-aspect-ratio micro-mirrors fabricated on a cylindrical elastomeric substrate, functionally inspired by natural reflecting superposition compound eyes. Our device can perform one-dimensional focusing and beam-shaping comparable to conventional refraction-based cylindrical lenses, while avoiding chromatic aberration. The focal length of our cylindrical lens is 1.035 mm, suitable for micro-optical systems. Moreover, it demonstrates a wide field of view of 152° without distortion, as well as modest spherical aberrations. Our work could be applied to diverse applications including laser diode collimation, barcode scanning, holography, digital projection display, microlens arrays, and optical microscopy.

  19. Genetic analysis of a novel broad-spectrum powdery mildew resistance gene from the wheat-Agropyron cristatum introgression line Pubing 74.

    Science.gov (United States)

    Lu, Yuqing; Yao, Miaomiao; Zhang, Jinpeng; Song, Liqiang; Liu, Weihua; Yang, Xinming; Li, Xiuquan; Li, Lihui

    2016-09-01

    A novel broad-spectrum powdery mildew resistance gene PmPB74 was identified in wheat- Agropyron cristatum introgression line Pubing 74. Development of wheat cultivars with broad-spectrum, durable resistance to powdery mildew has been restricted by lack of superior genetic resources. In this study, a wheat-A. cristatum introgression line Pubing 74, originally selected from a wide cross between the common wheat cultivar Fukuhokomugi (Fukuho) and Agropyron cristatum (L.) Gaertn (2n = 4x = 28; genome PPPP), displayed resistance to powdery mildew at both the seedling and adult stages. The putative alien chromosomal fragment in Pubing 74 was below the detection limit of genomic in situ hybridization (GISH), but evidence for other non-GISH-detectable introgressions was provided by the presence of three STS markers specific to A. cristatum. Genetic analysis indicated that Pubing 74 carried a single dominant gene for powdery mildew resistance, temporarily designated PmPB74. Molecular mapping showed that PmPB74 was located on wheat chromosome arm 5DS, and flanked by markers Xcfd81 and HRM02 at genetic distances of 2.5 and 1.7 cM, respectively. Compared with other lines with powdery mildew resistance gene(s) on wheat chromosome arm 5DS, Pubing 74 was resistant to all 28 Blumeria graminis f. sp tritici (Bgt) isolates from different wheat-producing regions of northern China. Allelism tests indicated that PmPB74 was not allelic to PmPB3558 or Pm2. Our work showed that PmPB74 is a novel gene with broad resistance to powdery mildew, and hence will be helpful in broadening the genetic basis of powdery mildew resistance in wheat.

  20. Oral chlorhexidine in the prevention of ventilator- associated ...

    African Journals Online (AJOL)

    of oral chlorhexidine versus power tooth brushing, Listerine, placebos, bicarbonate isotonic serum rinse ... Treatment with chlorhexidine decreased the risk of VAP by 36%. ... Sources for relevant studies included the following databases: the.

  1. DETERMINATION OF CHLORHEXIDINE IN SALIVA AND IN AQUEOUS-SOLUTIONS

    NARCIS (Netherlands)

    de Vries, J.; Ruben, J; Arends, J.

    1991-01-01

    A new method is presented for the determination of chlorhexidine in centrifuged saliva and in aqueous solutions by means of fluorescence spectroscopy. The method relies on complex formation between chlorhexidine and eosin. The fluorescence value of the chlorhexidine-eosin system decreases with

  2. A natural component from Euphorbia humifusa Willd displays novel, broad-spectrum anti-influenza activity by blocking nuclear export of viral ribonucleoprotein

    Energy Technology Data Exchange (ETDEWEB)

    Chang, So Young; Park, Ji Hoon [Respiratory Viruses Research Laboratory, Discovery Biology Department, Institut Pasteur Korea, 16, Daewangpangyo-ro 712 Beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do, 463-400 (Korea, Republic of); Kim, Young Ho; Kang, Jong Seong [College of Pharmacy, Chungnam National University, Daejeon, 305-764 (Korea, Republic of); Min, Ji-Young, E-mail: jiyoung.min@ip-korea.org [Respiratory Viruses Research Laboratory, Discovery Biology Department, Institut Pasteur Korea, 16, Daewangpangyo-ro 712 Beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do, 463-400 (Korea, Republic of)

    2016-03-04

    The need to develop anti-influenza drugs with novel antiviral mechanisms is urgent because of the rapid rate of antigenic mutation and the emergence of drug-resistant viruses. We identified a novel anti-influenza molecule by screening 861 plant-derived natural components using a high-throughput image-based assay that measures inhibition of the influenza virus infection. 1,3,4,6-tetra-O-galloyl-β-D-glucopyranoside (TGBG) from Euphorbia humifusa Willd showed broad-spectrum anti-influenza activity against two seasonal influenza A strains, A/California/07/2009 (H1N1) and A/Perth/16/2009 (H3N2), and seasonal influenza B strain B/Florida/04/2006. We investigated the mode of action of TGBG using neuraminidase activity inhibition and time-of-addition assays, which evaluate the viral release and entry steps, respectively. We found that TGBG exhibits a novel antiviral mechanism that differs from the FDA-approved anti-influenza drugs oseltamivir which inhibits viral release, and amantadine which inhibits viral entry. Immunofluorescence assay demonstrated that TGBG significantly inhibits nuclear export of influenza nucleoproteins (NP) during the early stages of infection causing NP to accumulate in the nucleus. In addition, influenza-induced activation of the Akt signaling pathway was suppressed by TGBG in a dose-dependent manner. These data suggest that a putative mode of action of TGBG involves inhibition of viral ribonucleoprotein (vRNP) export from the nucleus to the cytoplasm consequently disrupting the assembly of progeny virions. In summary, TGBG has potential as novel anti-influenza therapeutic with a novel mechanism of action. - Highlights: • The plant-derived natural product TGBG has broad-spectrum antiviral activity against seasonal influenza A and B viruses. • TGBG has a novel anti-viral mechanism of action that from differs from the currently available anti-influenza drugs. • TGBG hinders nuclear export of the influenza virus ribonucleoprotein (v

  3. A natural component from Euphorbia humifusa Willd displays novel, broad-spectrum anti-influenza activity by blocking nuclear export of viral ribonucleoprotein

    International Nuclear Information System (INIS)

    Chang, So Young; Park, Ji Hoon; Kim, Young Ho; Kang, Jong Seong; Min, Ji-Young

    2016-01-01

    The need to develop anti-influenza drugs with novel antiviral mechanisms is urgent because of the rapid rate of antigenic mutation and the emergence of drug-resistant viruses. We identified a novel anti-influenza molecule by screening 861 plant-derived natural components using a high-throughput image-based assay that measures inhibition of the influenza virus infection. 1,3,4,6-tetra-O-galloyl-β-D-glucopyranoside (TGBG) from Euphorbia humifusa Willd showed broad-spectrum anti-influenza activity against two seasonal influenza A strains, A/California/07/2009 (H1N1) and A/Perth/16/2009 (H3N2), and seasonal influenza B strain B/Florida/04/2006. We investigated the mode of action of TGBG using neuraminidase activity inhibition and time-of-addition assays, which evaluate the viral release and entry steps, respectively. We found that TGBG exhibits a novel antiviral mechanism that differs from the FDA-approved anti-influenza drugs oseltamivir which inhibits viral release, and amantadine which inhibits viral entry. Immunofluorescence assay demonstrated that TGBG significantly inhibits nuclear export of influenza nucleoproteins (NP) during the early stages of infection causing NP to accumulate in the nucleus. In addition, influenza-induced activation of the Akt signaling pathway was suppressed by TGBG in a dose-dependent manner. These data suggest that a putative mode of action of TGBG involves inhibition of viral ribonucleoprotein (vRNP) export from the nucleus to the cytoplasm consequently disrupting the assembly of progeny virions. In summary, TGBG has potential as novel anti-influenza therapeutic with a novel mechanism of action. - Highlights: • The plant-derived natural product TGBG has broad-spectrum antiviral activity against seasonal influenza A and B viruses. • TGBG has a novel anti-viral mechanism of action that from differs from the currently available anti-influenza drugs. • TGBG hinders nuclear export of the influenza virus ribonucleoprotein (v

  4. Transgenic Brassica rapa plants over-expressing eIF(iso)4E variants show broad-spectrum Turnip mosaic virus (TuMV) resistance.

    Science.gov (United States)

    Kim, Jinhee; Kang, Won-Hee; Hwang, Jeena; Yang, Hee-Bum; Dosun, Kim; Oh, Chang-Sik; Kang, Byoung-Cheorl

    2014-08-01

    The protein-protein interaction between VPg (viral protein genome-linked) of potyviruses and eIF4E (eukaryotic initiation factor 4E) or eIF(iso)4E of their host plants is a critical step in determining viral virulence. In this study, we evaluated the approach of engineering broad-spectrum resistance in Chinese cabbage (Brassica rapa) to Turnip mosaic virus (TuMV), which is one of the most important potyviruses, by a systematic knowledge-based approach to interrupt the interaction between TuMV VPg and B. rapa eIF(iso)4E. The seven amino acids in the cap-binding pocket of eIF(iso)4E were selected on the basis of other previous results and comparison of protein models of cap-binding pockets, and mutated. Yeast two-hybrid assay and co-immunoprecipitation analysis demonstrated that W95L, K150L and W95L/K150E amino acid mutations of B. rapa eIF(iso)4E interrupted its interaction with TuMV VPg. All eIF(iso)4E mutants were able to complement an eIF4E-knockout yeast strain, indicating that the mutated eIF(iso)4E proteins retained their function as a translational initiation factor. To determine whether these mutations could confer resistance, eIF(iso)4E W95L, W95L/K150E and eIF(iso)4E wild-type were over-expressed in a susceptible Chinese cabbage cultivar. Evaluation of the TuMV resistance of T1 and T2 transformants demonstrated that the over-expression of the eIF(iso)4E mutant forms can confer resistance to multiple TuMV strains. These data demonstrate the utility of knowledge-based approaches for the engineering of broad-spectrum resistance in Chinese cabbage. © 2014 BSPP AND JOHN WILEY & SONS LTD.

  5. Oral chlorhexidine and microbial contamination during endoscopy

    DEFF Research Database (Denmark)

    Donatsky, Anders Meller; Holzknecht, Barbara Juliane; Arpi, Magnus

    2013-01-01

    BACKGROUND: One of the biggest concerns associated with transgastric surgery is contamination and risk of intra-abdominal infection with microbes introduced from the access route. The purpose of this study was to evaluate the effect of oral decontamination with chlorhexidine on microbial contamin......BACKGROUND: One of the biggest concerns associated with transgastric surgery is contamination and risk of intra-abdominal infection with microbes introduced from the access route. The purpose of this study was to evaluate the effect of oral decontamination with chlorhexidine on microbial...... contamination of the endoscope. METHODS: In a prospective, randomized, single-blinded, clinical trial the effect of chlorhexidine mouth rinse was evaluated. As a surrogate for the risk of intra-abdominal contamination during transgastric surgery, microbial contamination of the endoscope during upper endoscopy...... microbial contamination of the endoscope, but micro-organisms with abscess forming capabilities were still present. PPI treatment significantly increased CFU and should be discontinued before transgastric surgery....

  6. Antimicrobial Peptides: a promising class of antimicrobial compounds against BWA and multi-drug resistant bacteria: in the spotlight: the lactoferrin chimera

    NARCIS (Netherlands)

    Bikker, F.J.; Sijbrandij, T.; Nazmi, K.; Bolscher, J.G.M.; Veerman, E.C.I.; Jansen, H-J.

    2014-01-01

    Anti-Microbial Peptides (AMPs) are part of the innate immune defense system and considered as promising lead compounds for the development of novel anti-bacterial agents. In general, AMPs are simple, short peptides with broad-spectrum activity against Gram-negative and Gram-positive bacteria, fungi,

  7. Efficacy of oral E1210, a new broad-spectrum antifungal with a novel mechanism of action, in murine models of candidiasis, aspergillosis, and fusariosis.

    Science.gov (United States)

    Hata, Katsura; Horii, Takaaki; Miyazaki, Mamiko; Watanabe, Nao-Aki; Okubo, Miyuki; Sonoda, Jiro; Nakamoto, Kazutaka; Tanaka, Keigo; Shirotori, Syuji; Murai, Norio; Inoue, Satoshi; Matsukura, Masayuki; Abe, Shinya; Yoshimatsu, Kentaro; Asada, Makoto

    2011-10-01

    E1210 is a first-in-class, broad-spectrum antifungal with a novel mechanism of action-inhibition of fungal glycosylphosphatidylinositol biosynthesis. In this study, the efficacies of E1210 and reference antifungals were evaluated in murine models of oropharyngeal and disseminated candidiasis, pulmonary aspergillosis, and disseminated fusariosis. Oral E1210 demonstrated dose-dependent efficacy in infections caused by Candida species, Aspergillus spp., and Fusarium solani. In the treatment of oropharyngeal candidiasis, E1210 and fluconazole each caused a significantly greater reduction in the number of oral CFU than the control treatment (P candidiasis model, mice treated with E1210, fluconazole, caspofungin, or liposomal amphotericin B showed significantly higher survival rates than the control mice (P candidiasis caused by azole-resistant Candida albicans or Candida tropicalis. A 24-h delay in treatment onset minimally affected the efficacy outcome of E1210 in the treatment of disseminated candidiasis. In the Aspergillus flavus pulmonary aspergillosis model, mice treated with E1210, voriconazole, or caspofungin showed significantly higher survival rates than the control mice (P candidiasis, pulmonary aspergillosis, and disseminated fusariosis. These data suggest that further studies to determine E1210's potential for the treatment of disseminated fungal infections are indicated.

  8. Protease-sensitive conformers in broad spectrum of distinct PrPSc structures in sporadic Creutzfeldt-Jakob disease are indicator of progression rate.

    Directory of Open Access Journals (Sweden)

    Chae Kim

    2011-09-01

    Full Text Available The origin, range, and structure of prions causing the most common human prion disease, sporadic Creutzfeldt-Jakob disease (sCJD, are largely unknown. To investigate the molecular mechanism responsible for the broad phenotypic variability of sCJD, we analyzed the conformational characteristics of protease-sensitive and protease-resistant fractions of the pathogenic prion protein (PrP(Sc using novel conformational methods derived from a conformation-dependent immunoassay (CDI. In 46 brains of patients homozygous for polymorphisms in the PRNP gene and exhibiting either Type 1 or Type 2 western blot pattern of the PrP(Sc, we identified an extensive array of PrP(Sc structures that differ in protease sensitivity, display of critical domains, and conformational stability. Surprisingly, in sCJD cases homozygous for methionine or valine at codon 129 of the PRNP gene, the concentration and stability of protease-sensitive conformers of PrP(Sc correlated with progression rate of the disease. These data indicate that sCJD brains exhibit a wide spectrum of PrP(Sc structural states, and accordingly argue for a broad spectrum of prion strains coding for different phenotypes. The link between disease duration, levels, and stability of protease-sensitive conformers of PrP(Sc suggests that these conformers play an important role in the pathogenesis of sCJD.

  9. Preclinical optimization of a broad-spectrum anti-bladder cancer tri-drug regimen via the Feedback System Control (FSC) platform

    Science.gov (United States)

    Liu, Qi; Zhang, Cheng; Ding, Xianting; Deng, Hui; Zhang, Daming; Cui, Wei; Xu, Hongwei; Wang, Yingwei; Xu, Wanhai; Lv, Lei; Zhang, Hongyu; He, Yinghua; Wu, Qiong; Szyf, Moshe; Ho, Chih-Ming; Zhu, Jingde

    2015-06-01

    Therapeutic outcomes of combination chemotherapy have not significantly advanced during the past decades. This has been attributed to the formidable challenges of optimizing drug combinations. Testing a matrix of all possible combinations of doses and agents in a single cell line is unfeasible due to the virtually infinite number of possibilities. We utilized the Feedback System Control (FSC) platform, a phenotype oriented approach to test 100 options among 15,625 possible combinations in four rounds of assaying to identify an optimal tri-drug combination in eight distinct chemoresistant bladder cancer cell lines. This combination killed between 82.86% and 99.52% of BCa cells, but only 47.47% of the immortalized benign bladder epithelial cells. Preclinical in vivo verification revealed its markedly enhanced anti-tumor efficacy as compared to its bi- or mono-drug components in cell line-derived tumor xenografts. The collective response of these pathways to component drugs was both cell type- and drug type specific. However, the entire spectrum of pathways triggered by the tri-drug regimen was similar in all four cancer cell lines, explaining its broad spectrum killing of BCa lines, which did not occur with its component drugs. Our findings here suggest that the FSC platform holdspromise for optimization of anti-cancer combination chemotherapy.

  10. The sun protection factor (SPF) inadequately defines broad spectrum photoprotection: demonstration using skin reconstructed in vitro exposed to UVA, UVBor UV-solar simulated radiation.

    Science.gov (United States)

    Bernerd, Françoise; Vioux, Corinne; Lejeune, François; Asselineau, Daniel

    2003-01-01

    Wavelength specific biological damage has been previously identified in human skin reconstructed in vitro. Sunburn cell and pyrimidine dimers were found after UVB exposure, and alterations of dermal fibroblasts after UVA exposure. These damages permitted us to discriminate UVB and UVA single absorbers. The present study shows that these biological effects can be obtained simultaneously by a combined UVB + UVA exposure using ultraviolet solar simulated light (UV-SSR), which represents a relevant UV source. In addition, the protection afforded by two broad spectrum sunscreen complex formulations was assessed after topical application. These two formulations displayed the same sun protection factor but different UVA protection factors determined by the persistent pigment darkening (PPD) method. Dose response experiments of UVA or UV-SSR showed that the preparation with the highest PF-UVA provided a better protection with regard to dermal damage compared to the other formulation. Using an original UVB source to obtain the UVB portion of SSR spectrum, the preparations provided the same protection. This study strikingly illustrates the fact that the photoprotection afforded by two sunscreen formulations having similar SPF values is not equal with regard to dermal damage related to photoaging.

  11. Ectopic expression of Arabidopsis broad-spectrum resistance gene RPW8.2 improves the resistance to powdery mildew in grapevine (Vitis vinifera).

    Science.gov (United States)

    Hu, Yang; Li, Yajuan; Hou, Fengjuan; Wan, Dongyan; Cheng, Yuan; Han, Yongtao; Gao, Yurong; Liu, Jie; Guo, Ye; Xiao, Shunyuan; Wang, Yuejin; Wen, Ying-Qiang

    2018-02-01

    Powdery mildew is the most economically important disease of cultivated grapevines worldwide. Here, we report that the Arabidopsis broad-spectrum disease resistance gene RPW8.2 could improve resistance to powdery mildew in Vitis vinifera cv. Thompson Seedless. The RPW8.2-YFP fusion gene was stably expressed in grapevines from either the constitutive 35S promoter or the native promoter (NP) of RPW8.2. The grapevine shoots and plantlets transgenic for 35S::RPW8.2-YFP showed reduced rooting and reduced growth at later development stages in the absence of any pathogens. Infection tests with an adapted grapevine powdery mildew isolate En NAFU1 showed that hyphal growth and sporulation were significantly restricted in transgenic grapevines expressing either of the two constructs. The resistance appeared to be attributable to the ectopic expression of RPW8.2, and associated with the enhanced encasement of the haustorial complex (EHC) and onsite accumulation of H 2 O 2 . In addition, the RPW8.2-YFP fusion protein showed focal accumulation around the fungal penetration sites. Transcriptome analysis revealed that ectopic expression of RPW8.2 in grapevines not only significantly enhanced salicylic acid-dependent defense signaling, but also altered expression of other phytohormone-associated genes. Taken together, our results indicate that RPW8.2 could be utilized as a transgene for improving resistance against powdery mildew in grapevines. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Efficacy of Oral E1210, a New Broad-Spectrum Antifungal with a Novel Mechanism of Action, in Murine Models of Candidiasis, Aspergillosis, and Fusariosis▿

    Science.gov (United States)

    Hata, Katsura; Horii, Takaaki; Miyazaki, Mamiko; Watanabe, Nao-aki; Okubo, Miyuki; Sonoda, Jiro; Nakamoto, Kazutaka; Tanaka, Keigo; Shirotori, Syuji; Murai, Norio; Inoue, Satoshi; Matsukura, Masayuki; Abe, Shinya; Yoshimatsu, Kentaro; Asada, Makoto

    2011-01-01

    E1210 is a first-in-class, broad-spectrum antifungal with a novel mechanism of action—inhibition of fungal glycosylphosphatidylinositol biosynthesis. In this study, the efficacies of E1210 and reference antifungals were evaluated in murine models of oropharyngeal and disseminated candidiasis, pulmonary aspergillosis, and disseminated fusariosis. Oral E1210 demonstrated dose-dependent efficacy in infections caused by Candida species, Aspergillus spp., and Fusarium solani. In the treatment of oropharyngeal candidiasis, E1210 and fluconazole each caused a significantly greater reduction in the number of oral CFU than the control treatment (P candidiasis model, mice treated with E1210, fluconazole, caspofungin, or liposomal amphotericin B showed significantly higher survival rates than the control mice (P candidiasis caused by azole-resistant Candida albicans or Candida tropicalis. A 24-h delay in treatment onset minimally affected the efficacy outcome of E1210 in the treatment of disseminated candidiasis. In the Aspergillus flavus pulmonary aspergillosis model, mice treated with E1210, voriconazole, or caspofungin showed significantly higher survival rates than the control mice (P candidiasis, pulmonary aspergillosis, and disseminated fusariosis. These data suggest that further studies to determine E1210's potential for the treatment of disseminated fungal infections are indicated. PMID:21788462

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

    Science.gov (United States)

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

    2017-06-01

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

  14. An application in cheddar cheese manufacture for a strain of Lactococcus lactis producing a novel broad-spectrum bacteriocin, lacticin 3147.

    Science.gov (United States)

    Ryan, M P; Rea, M C; Hill, C; Ross, R P

    1996-01-01

    Lactococcus lactis DPC3147, a strain isolated from an Irish kefir grain, produces a bacteriocin with a broad spectrum of inhibition. The bacteriocin produced is heat stable, particularly at a low pH, and inhibits nisin-producing (Nip+) lactococci. On the basis of the observation that the nisin structural gene (nisA) does not hybridize to DPC3147 genomic DNA, the bacteriocin produced was considered novel and designated lacticin 3147. The genetic determinants which encode lacticin 3147 are contained on a 63-kb plasmid, which was conjugally mobilized to a commercial cheese starter, L. lactis subsp. cremoris DPC4268. The resultant transconjugant, DPC4275, both produces and is immune to lacticin 3147. The ability of lacticin 3147-producing lactococci to perform as cheddar cheese starters was subsequently investigated in cheesemaking trials. Bacteriocin-producing starters (which included the transconjugant strain DPC4275) produced acid at rates similar to those of commercial strains. The level of lacticin 3147 produced in cheese remained constant over 6 months of ripening and correlated with a significant reduction in the levels of nonstarter lactic acid bacteria. Such results suggest that these starters provide a means of controlling developing microflora in ripened fermented products. PMID:8593062

  15. CRA-026440: a potent, broad-spectrum, hydroxamic histone deacetylase inhibitor with antiproliferative and antiangiogenic activity in vitro and in vivo.

    Science.gov (United States)

    Cao, Z Alexander; Bass, Kathryn E; Balasubramanian, Sriram; Liu, Liang; Schultz, Brian; Verner, Erik; Dai, Yuqin; Molina, Rafael A; Davis, Jack R; Misialek, Shawn; Sendzik, Martin; Orr, Christine J; Leung, Ling; Callan, Ondine; Young, Peter; Dalrymple, Stacie A; Buggy, Joseph J

    2006-07-01

    CRA-026440 is a novel, broad-spectrum, hydroxamic acid-based inhibitor of histone deacetylase (HDAC) that shows antitumor and antiangiogenic activities in vitro and in vivo preclinically. CRA-026440 inhibited pure recombinant isozymes HDAC1, HDAC2, HDAC3/SMRT, HDAC6, HDAC8, and HDAC10 in the nanomolar range. Treatment of cultured tumor cell lines grown in vitro with CRA-026440 resulted in the accumulation of acetylated histone and acetylated tubulin, leading to an inhibition of tumor cell growth and the induction of apoptosis. CRA-026440 inhibited ex vivo angiogenesis in a dose-dependent manner. CRA-026440 parenterally given to mice harboring HCT116 or U937 human tumor xenografts resulted in a statistically significant reduction in tumor growth. CRA-026440, when used in combination with Avastin, achieved greater preclinical efficacy in HCT 116 colorectal tumor model. Inhibition of tumor growth was accompanied by an increase in the acetylation of alpha-tubulin in peripheral blood mononuclear cells and an alteration in the expression of many genes in the tumors, including several involved in angiogenesis, apoptosis, and cell growth. These results reveal CRA-026440 to be a novel HDAC inhibitor with potent antitumor activity.

  16. A P25/(NH4)xWO3 hybrid photocatalyst with broad spectrum photocatalytic properties under UV, visible, and near-infrared irradiation.

    Science.gov (United States)

    Yang, Linfen; Liu, Bin; Liu, Tongyao; Ma, Xinlong; Li, Hao; Yin, Shu; Sato, Tsugio; Wang, Yuhua

    2017-04-03

    In this study, a series of hybrid nanostructured photocatalysts P25/(NH 4 ) x WO 3 nanocomposites with the average crystallite size of P25 and (NH 4 ) x WO 3 of the sample was calculated to be about 30 nm and 130 nm, were successfully synthesized via a simple one-step hydrothermal method. The as-obtained samples was characterized by transmission electron microscopy (TEM), which implies that the P25/(NH 4 ) x WO 3 nanocomposites are fabricated with favourable nanosizd interfacial. The XPS results confirmed that the obtained sample consists of mixed chemical valences of W 5+ and W 6+ , the low-valance W 5+ sites could be the origin of NIR absorption. As revealed by optical absorption results, P25/(NH 4 ) x WO 3 nanocomposites possess high optical absorption in the whole solar spectrum of 200-2500 nm. Benefiting from this unique photo-absorption property and the synergistic effect of P25 and (NH 4 ) x WO 3 , broad spectrum response photocatalytic activities covering UV, visible and near infrared regions on degradation of Rhodamine B have been realized by P25/(NH 4 ) x WO 3 nanocomposites. Meanwhile, the stability of photocatalysts was examined by the XRD and XPS of the photocatalysts after the reaction. The results show that P25/(NH 4 ) x WO 3 photocatalysts has a brilliant application prospect in the energy utilization to solve deteriorating environmental issues.

  17. Oldest human occupation of Wallacea at Laili Cave, Timor-Leste, shows broad-spectrum foraging responses to late Pleistocene environments

    Science.gov (United States)

    Hawkins, Stuart; O'Connor, Sue; Maloney, Tim Ryan; Litster, Mirani; Kealy, Shimona; Fenner, Jack N.; Aplin, Ken; Boulanger, Clara; Brockwell, Sally; Willan, Richard; Piotto, Elena; Louys, Julien

    2017-09-01

    The Wallacea Archipelago provides an extraordinary laboratory for the study of human colonisation and adaptation, yet few detailed archaeological studies have been conducted in the region that span the earliest phase of human settlement. Laili Cave, in northern Timor-Leste, preserves the oldest human occupation in this insular region with a cultural sequence spanning 11,200 to 44,600 cal BP. Small-bodied vertebrates and invertebrates were recovered to the lowest excavated levels, associated with highly concentrated stone artefacts. We report on human behavioural adaptations within the context of Pleistocene environments and changing landscapes using zooarchaeological, stone artefact, bathymetric, and experimental isotopic analyses. Results indicate that Pleistocene humans used the abundant local chert liberally and engaged in mobile broad-spectrum exploitation of invertebrates and fishes from marine, estuarine, and freshwater environments within close proximity of Laili Cave. The faunal assemblage indicates heterogeneous but relatively stable environments during the late Pleistocene. Variability in subsistence strategies over time appears to be a response to changing landscapes and concomitant local resources. This record contrasts with marine specialisations evident from other sites in Timor-Leste and within the broader Wallacean region.

  18. Varespladib (LY315920 Appears to Be a Potent, Broad-Spectrum, Inhibitor of Snake Venom Phospholipase A2 and a Possible Pre-Referral Treatment for Envenomation

    Directory of Open Access Journals (Sweden)

    Matthew Lewin

    2016-08-01

    Full Text Available Snakebite remains a neglected medical problem of the developing world with up to 125,000 deaths each year despite more than a century of calls to improve snakebite prevention and care. An estimated 75% of fatalities from snakebite occur outside the hospital setting. Because phospholipase A2 (PLA2 activity is an important component of venom toxicity, we sought candidate PLA2 inhibitors by directly testing drugs. Surprisingly, varespladib and its orally bioavailable prodrug, methyl-varespladib showed high-level secretory PLA2 (sPLA2 inhibition at nanomolar and picomolar concentrations against 28 medically important snake venoms from six continents. In vivo proof-of-concept studies with varespladib had striking survival benefit against lethal doses of Micrurus fulvius and Vipera berus venom, and suppressed venom-induced sPLA2 activity in rats challenged with 100% lethal doses of M. fulvius venom. Rapid development and deployment of a broad-spectrum PLA2 inhibitor alone or in combination with other small molecule inhibitors of snake toxins (e.g., metalloproteases could fill the critical therapeutic gap spanning pre-referral and hospital setting. Lower barriers for clinical testing of safety tested, repurposed small molecule therapeutics are a potentially economical and effective path forward to fill the pre-referral gap in the setting of snakebite.

  19. Sunscreens with broad-spectrum absorption decrease the trans TO cis photoisomerization of urocanic acid in the human stratum corneum after multiple UV light exposures

    International Nuclear Information System (INIS)

    Krien, P.M.; Moyal, D.

    1994-01-01

    The trans to cis photoisomerization of urocanic acid (UCA) in skin is considered to play an important role in the mechanism of immunosuppression. We have investigated the effects of skin type and various sunscreens with low sun protection factor (SPF) on the UV-induced cis-UCA formation in human skin after exposure to artificial UV light. The rate of cis-UCA formation depends little on the skin type and is reduced by topical application of sunscreens. The rate of cis-UCA formation decreases with increasing SPF and only broad-spectrum, highly protective sunscreens offer protection against the UV-induced formation of cis-UCA, which accumulates in the stratum corneum after multiple UV exposures. A theoretical approach to estimate the distribution of cis-UCA after irradiation indicates that this compound may diffuse into the deeper layers of the epidermis with D ∼ 10 -17 m 2 /s, and that its elimination from the stratum corneum is mainly due to desquamation. (author)

  20. Evaluation of the antimicrobial and physical properties of an orthodontic photo-activated adhesive modified with an antiplaque agent: An in vitro study

    Directory of Open Access Journals (Sweden)

    Chanjyot Singh

    2013-01-01

    Results: The findings indicated that (1 addition of chlorhexidine to the orthodontic composite resin enhanced its antimicrobial properties, (2 there was no significant difference between the bond strengths of the control and the experimental resins tested after 24 h and 25 days and (3 maximum release of chlorhexidine from the modified resin was much higher than the minimum inhibitory concentration level.

  1. Perawatan Ulang Saluran Akar Insisivus Lateralis Kiri Maksila dengan Medikamen Kalsium Hidroksida-Chlorhexidine

    Directory of Open Access Journals (Sweden)

    Ni Gusti Ayu Ariani

    2013-06-01

    Full Text Available Banyak faktor yang menyebabkan kegagalan terapi endodontik antara lain pembersihan dan membentuk saluran akar yang tidak sempurna dan obturasi tidak hermetis sehingga menyebabkan kurangnya kemampuan untuk menghilangkan mikroorganisme yang ada. Saluran akar yang terinfeksi membutuhkan suatu medikamen untuk menunjang keberhasilan dalam perawatan saluran akar.Kalsium hidroksida merupakan salah satu bahan medikamen yang efektif karena memiliki sifat antibakteri dengan spektrum luas, pH tinggi, biokompatibilitas baik, mampu menetralkan endotoksin bakteri, memiliki sifat toksik yang paling rendah, serta menstimulasi pembentukan jaringan keras. Tujuan laporan kasus untuk menunjukan keberhasilan perawatan ulang saluran akar gigi insisivus lateralis kiri maksila dengan lesi periapikal menggunakan medikamen kalsium hidroksida- chlorhexidine. Pasien wanita umur 53 tahun, gigi insisivus lateralis kiri maksila dengan lesi periapikal.Radiografi tampak obturasi kurang hermetis dan radiolusen daerah periapikal. Perawatan ulang saluran akar,diikuti pemasangan pasak fiber frefabricated dan restorasi porselin fuse metal.Keseimpulan setelah evaluasi setelah enam bulan pasca perawatan ulang saluran akar, radiografi menunjukan radiolusen mengecil dan gigi dapat berfungsi dengan normal. Re-Treatment of Root Canal of Maxillary Left Lateral Incisor with Calcium Hydroxide-Chlorhexidine Medicament. There are many factors that cause failure of endodontic therapy. For instances, incomplete cleaning and shaping of root canal and inadequate obturation that results in difficulty to remove the microorganisms. Infected root canal requires a medicament for the success of the root canal treatment. Calcium hydroxide is one of the effective ingredients as medicament because it has broad spectrum antibacterial properties, high pH, good biocompatibility, and it is able to neutralize bacterial endotoxins, decrease tissue toxicity, and stimulate the formation of hard tissue. The purpose

  2. A novel blast resistance gene, Pi54rh cloned from wild species of rice, Oryza rhizomatis confers broad spectrum resistance to Magnaporthe oryzae.

    Science.gov (United States)

    Das, Alok; Soubam, D; Singh, P K; Thakur, S; Singh, N K; Sharma, T R

    2012-06-01

    The dominant rice blast resistance gene, Pi54 confers resistance to Magnaporthe oryzae in different parts of India. In our effort to identify more effective forms of this gene, we isolated an orthologue of Pi54 named as Pi54rh from the blast-resistant wild species of rice, Oryza rhizomatis, using allele mining approach and validated by complementation. The Pi54rh belongs to CC-NBS-LRR family of disease resistance genes with a unique Zinc finger (C(3)H type) domain. The 1,447 bp Pi54rh transcript comprises of 101 bp 5'-UTR, 1,083 bp coding region and 263 bp 3'-UTR, driven by pathogen inducible promoter. We showed the extracellular localization of Pi54rh protein and the presence of glycosylation, myristoylation and phosphorylation sites which implicates its role in signal transduction process. This is in contrast to other blast resistance genes that are predicted to be intracellular NBS-LRR-type resistance proteins. The Pi54rh was found to express constitutively at basal level in the leaves, but upregulates 3.8-fold at 96 h post-inoculation with the pathogen. Functional validation of cloned Pi54rh gene using complementation test showed high degree of resistance to seven isolates of M. oryzae collected from different geographical locations of India. In this study, for the first time, we demonstrated that a rice blast resistance gene Pi54rh cloned from wild species of rice provides broad spectrum resistance to M. oryzae hence can be used in rice improvement breeding programme.

  3. Linear biocompatible glyco-polyamidoamines as dual action mode virus infection inhibitors with potential as broad-spectrum microbicides for sexually transmitted diseases

    Science.gov (United States)

    Mauro, Nicolò; Ferruti, Paolo; Ranucci, Elisabetta; Manfredi, Amedea; Berzi, Angela; Clerici, Mario; Cagno, Valeria; Lembo, David; Palmioli, Alessandro; Sattin, Sara

    2016-09-01

    The initial steps of viral infections are mediated by interactions between viral proteins and cellular receptors. Blocking the latter with high-affinity ligands may inhibit infection. DC-SIGN, a C-type lectin receptor expressed by immature dendritic cells and macrophages, mediates human immunodeficiency virus (HIV) infection by recognizing mannose clusters on the HIV-1 gp120 envelope glycoprotein. Mannosylated glycodendrimers act as HIV entry inhibitors thanks to their ability to block this receptor. Previously, an amphoteric, but prevailingly cationic polyamidoamine named AGMA1 proved effective as infection inhibitor for several heparan sulfate proteoglycan-dependent viruses, such as human papilloma virus HPV-16 and herpes simplex virus HSV-2. An amphoteric, but prevailingly anionic PAA named ISA23 proved inactive. It was speculated that the substitution of mannosylated units for a limited percentage of AGMA1 repeating units, while imparting anti-HIV activity, would preserve the fundamentals of its HPV-16 and HSV-2 infection inhibitory activity. In this work, four biocompatible linear PAAs carrying different amounts of mannosyl-triazolyl pendants, Man-ISA7, Man-ISA14, Man-AGMA6.5 and Man-AGMA14.5, were prepared by reaction of 2-(azidoethyl)-α-D-mannopyranoside and differently propargyl-substituted AGMA1 and ISA23. All mannosylated PAAs inhibited HIV infection. Both Man-AGMA6.5 and Man-AGMA14.5 maintained the HPV-16 and HSV-2 activity of the parent polymer, proving broad-spectrum, dual action mode virus infection inhibitors.

  4. Design, synthesis and crystallographic analysis of nitrile-based broad-spectrum peptidomimetic inhibitors for coronavirus 3C-like proteases.

    Science.gov (United States)

    Chuck, Chi-Pang; Chen, Chao; Ke, Zhihai; Wan, David Chi-Cheong; Chow, Hak-Fun; Wong, Kam-Bo

    2013-01-01

    Coronaviral infection is associated with up to 5% of respiratory tract diseases. The 3C-like protease (3CL(pro)) of coronaviruses is required for proteolytic processing of polyproteins and viral replication, and is a promising target for the development of drugs against coronaviral infection. We designed and synthesized four nitrile-based peptidomimetic inhibitors with different N-terminal protective groups and different peptide length, and examined their inhibitory effect on the in-vitro enzymatic activity of 3CL(pro) of severe-acute-respiratory-syndrome-coronavirus. The IC(50) values of the inhibitors were in the range of 4.6-49 μM, demonstrating that the nitrile warhead can effectively inactivate the 3CL(pro) autocleavage process. The best inhibitor, Cbz-AVLQ-CN with an N-terminal carbobenzyloxy group, was ~10x more potent than the other inhibitors tested. Crystal structures of the enzyme-inhibitor complexes showed that the nitrile warhead inhibits 3CL(pro) by forming a covalent bond with the catalytic Cys145 residue, while the AVLQ peptide forms a number of favourable interactions with the S1-S4 substrate-binding pockets. We have further showed that the peptidomimetic inhibitor, Cbz-AVLQ-CN, has broad-spectrum inhibition against 3CL(pro) from human coronavirus strains 229E, NL63, OC43, HKU1, and infectious bronchitis virus, with IC(50) values ranging from 1.3 to 3.7 μM, but no detectable inhibition against caspase-3. In summary, we have shown that the nitrile-based peptidomimetic inhibitors are effective against 3CL(pro), and they inhibit 3CL(pro) from a broad range of coronaviruses. Our results provide further insights into the future design of drugs that could serve as a first line defence against coronaviral infection. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  5. Induction of a peptide with activity against a broad spectrum of pathogens in the Aedes aegypti salivary gland, following Infection with Dengue Virus.

    Directory of Open Access Journals (Sweden)

    Natthanej Luplertlop

    2011-01-01

    Full Text Available The ultimate stage of the transmission of Dengue Virus (DENV to man is strongly dependent on crosstalk between the virus and the immune system of its vector Aedes aegypti (Ae. aegypti. Infection of the mosquito's salivary glands by DENV is the final step prior to viral transmission. Therefore, in the present study, we have determined the modulatory effects of DENV infection on the immune response in this organ by carrying out a functional genomic analysis of uninfected salivary glands and salivary glands of female Ae. aegypti mosquitoes infected with DENV. We have shown that DENV infection of salivary glands strongly up-regulates the expression of genes that encode proteins involved in the vector's innate immune response, including the immune deficiency (IMD and Toll signalling pathways, and that it induces the expression of the gene encoding a putative anti-bacterial, cecropin-like, peptide (AAEL000598. Both the chemically synthesized non-cleaved, signal peptide-containing gene product of AAEL000598, and the cleaved, mature form, were found to exert, in addition to antibacterial activity, anti-DENV and anti-Chikungunya viral activity. However, in contrast to the mature form, the immature cecropin peptide was far more effective against Chikungunya virus (CHIKV and, furthermore, had strong anti-parasite activity as shown by its ability to kill Leishmania spp. Results from circular dichroism analysis showed that the immature form more readily adopts a helical conformation which would help it to cause membrane permeabilization, thus permitting its transfer across hydrophobic cell surfaces, which may explain the difference in the anti-pathogenic activity between the two forms. The present study underscores not only the importance of DENV-induced cecropin in the innate immune response of Ae. aegypti, but also emphasizes the broad-spectrum anti-pathogenic activity of the immature, signal peptide-containing form of this peptide.

  6. Molecular characterisation of the broad-spectrum resistance to powdery mildew conferred by the Stpk-V gene from the wild species Haynaldia villosa.

    Science.gov (United States)

    Qian, C; Cui, C; Wang, X; Zhou, C; Hu, P; Li, M; Li, R; Xiao, J; Wang, X; Chen, P; Xing, L; Cao, A

    2017-11-01

    A key member of the Pm21 resistance gene locus, Stpk-V, derived from Haynaldia villosa, was shown to confer broad-spectrum resistance to wheat powdery mildew. The present study was planned to investigate the resistance mechanism mediated by Stpk-V. Transcriptome analysis was performed in Stpk-V transgenic plants and recipient Yangmai158 upon Bgt infection, and detailed histochemical observations were conducted. Chromosome location of Stpk-V orthologous genes in Triticeae species was conducted for evolutionary study and over-expression of Stpk-V both in barley and Arabidopsis was performed for functional study. The transcriptome results indicate, at the early infection stage, the ROS pathway, JA pathway and some PR proteins associated with the SA pathway were activated in both the resistant Stpk-V transgenic plants and susceptible Yangmai158. However, at the later infection stage, the genes up-regulated at the early stage were continuously held only in the transgenic plants, and a large number of new genes were also activated in the transgenic plants but not in Yangmai158. Results indicate that sustained activation of the early response genes combined with later-activated genes mediated by Stpk-V is critical for resistance in Stpk-V transgenic plants. Stpk-V orthologous genes in the representative grass species are all located on homologous group six chromosomes, indicating that Stpk-V is an ancient gene in the grasses. Over-expression of Stpk-V enhanced host resistance to powdery mildew in barley but not in Arabidopsis. Our results enable a better understanding of the resistance mechanism mediated by Stpk-V, and establish a solid foundation for its use in cereal breeding as a gene resource. © 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

  7. Microbiota Disruption Induced by Early Use of Broad-Spectrum Antibiotics Is an Independent Risk Factor of Outcome after Allogeneic Stem Cell Transplantation.

    Science.gov (United States)

    Weber, Daniela; Jenq, Robert R; Peled, Jonathan U; Taur, Ying; Hiergeist, Andreas; Koestler, Josef; Dettmer, Katja; Weber, Markus; Wolff, Daniel; Hahn, Joachim; Pamer, Eric G; Herr, Wolfgang; Gessner, André; Oefner, Peter J; van den Brink, Marcel R M; Holler, Ernst

    2017-05-01

    In allogeneic stem cell transplantation (ASCT), systemic broad-spectrum antibiotics are frequently used for treatment of infectious complications, but their effect on microbiota composition is still poorly understood. This retrospective analysis of 621 patients who underwent ASCT at the University Medical Center of Regensburg and Memorial Sloan Kettering Cancer Center in New York assessed the impact of timing of peritransplant antibiotic treatment on intestinal microbiota composition as well as transplant-related mortality (TRM) and overall survival. Early exposure to antibiotics was associated with lower urinary 3-indoxyl sulfate levels (P antibiotic treatment, which was particularly significant (P = .005) for Clostridium cluster XIVa in the Regensburg group. Earlier antibiotic treatment before ASCT was further associated with a higher TRM (34%, 79/236) compared with post-ASCT (21%, 62/297, P = .001) or no antibiotics (7%, 6/88, P antibiotic treatment was the dominant independent risk factor for TRM (HR, 2.0; P ≤ .001) in multivariate analysis besides increase age (HR, 2.15; P = .004), reduced Karnofsky performance status (HR, 1.47; P = .03), and female donor-male recipient sex combination (HR, 1.56; P = .02) A competing risk analysis revealed the independent effect of early initiation of antibiotics on graft-versus-host disease-related TRM (P = .004) in contrast to infection-related TRM and relapse (not significant). The poor outcome associated with early administration of antibiotic therapy that is active against commensal organisms, and specifically the possibly protective Clostridiales, calls for the use of Clostridiales-sparing antibiotics and rapid restoration of microbiota diversity after cessation of antibiotic treatment. Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  8. Phosphatase Inhibitors Function as Novel, Broad Spectrum Botulinum Neurotoxin Antagonists in Mouse and Human Embryonic Stem Cell-Derived Motor Neuron-Based Assays.

    Directory of Open Access Journals (Sweden)

    Erkan Kiris

    Full Text Available There is an urgent need to develop novel treatments to counter Botulinum neurotoxin (BoNT poisoning. Currently, the majority of BoNT drug development efforts focus on directly inhibiting the proteolytic components of BoNT, i.e. light chains (LC. Although this is a rational approach, previous research has shown that LCs are extremely difficult drug targets and that inhibiting multi-serotype BoNTs with a single LC inhibitor may not be feasible. An alternative approach would target neuronal pathways involved in intoxication/recovery, rather than the LC itself. Phosphorylation-related mechanisms have been implicated in the intoxication pathway(s of BoNTs. However, the effects of phosphatase inhibitors upon BoNT activity in the physiological target of BoNTs, i.e. motor neurons, have not been investigated. In this study, a small library of phosphatase inhibitors was screened for BoNT antagonism in the context of mouse embryonic stem cell-derived motor neurons (ES-MNs. Four inhibitors were found to function as BoNT/A antagonists. Subsequently, we confirmed that these inhibitors protect against BoNT/A in a dose-dependent manner in human ES-MNs. Additionally, these compounds provide protection when administered in post-intoxication scenario. Importantly, the inhibitors were also effective against BoNT serotypes B and E. To the best of our knowledge, this is the first study showing phosphatase inhibitors as broad-spectrum BoNT antagonists.

  9. Chlorhexidine-releasing implant coating on intramedullary nail reduces infection in a rat model

    Directory of Open Access Journals (Sweden)

    SM Shiels

    2018-03-01

    Full Text Available The use of internal intramedullary nails for long bone fracture fixation is a common practice among surgeons. Bacteria naturally attach to these devices, increasing the risk for wound infection, which can result in non- or malunion, additional surgical procedures and extended hospital stays. Intramedullary nail surface properties can be modified to reduce bacterial colonisation and potentially infectious complications. In the current study, a coating combining a non-fouling property with leaching chlorhexidine for orthopaedic implantation was tested. Coating stability and chlorhexidine release were evaluated in vitro. Using a rat model of intramedullary fixation and infection, the effect of the coating on microbial colonisation and fracture healing was evaluated in vivo by quantitative microbiology, micro-computed tomography, plain radiography, three-point bending and/or histology. Low dose systemic cefazolin was administered to increase the similarities to clinical practice, without overshadowing the effect of the anti-infective coating. When introduced into a contaminated wound, the non-fouling chlorhexidine-coated implant reduced the overall bacteria colonisation within the bone and on the implant, reduced the osteolysis and increased the radiographic union, confirming its potential for reducing complications in wounds at high risk of infection. However, when implanted into a sterile wound, non-union increased. Further studies are required to best optimise the anti-microbial effectiveness, while not sacrificing fracture union.

  10. Synthetic biology platform technologies for antimicrobial applications.

    Science.gov (United States)

    Braff, Dana; Shis, David; Collins, James J

    2016-10-01

    The growing prevalence of antibiotic resistance calls for new approaches in the development of antimicrobial therapeutics. Likewise, improved diagnostic measures are essential in guiding the application of targeted therapies and preventing the evolution of therapeutic resistance. Discovery platforms are also needed to form new treatment strategies and identify novel antimicrobial agents. By applying engineering principles to molecular biology, synthetic biologists have developed platforms that improve upon, supplement, and will perhaps supplant traditional broad-spectrum antibiotics. Efforts in engineering bacteriophages and synthetic probiotics demonstrate targeted antimicrobial approaches that can be fine-tuned using synthetic biology-derived principles. Further, the development of paper-based, cell-free expression systems holds promise in promoting the clinical translation of molecular biology tools for diagnostic purposes. In this review, we highlight emerging synthetic biology platform technologies that are geared toward the generation of new antimicrobial therapies, diagnostics, and discovery channels. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Antimicrobial-Coated Granules for Disinfecting Water

    Science.gov (United States)

    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.

  12. Antimicrobial efficacy of the combinations of Acacia nilotica, Murraya koenigii (Linn. Sprengel, Eucalyptus, and Psidium guajava on primary plaque colonizers: An in vitro study

    Directory of Open Access Journals (Sweden)

    Byalakere Rudraiah Chandra Shekar

    2016-01-01

    Conclusion: All the triple and quadruple combinations of the plant extracts offered antimicrobial benefits either superior or comparable to 0.2% chlorhexidine against S. mutans, S. sanguis, and S. salivarius.

  13. Extracellular dextran and DNA affect the formation of Enterococcus faecalis biofilms and their susceptibility to 2% chlorhexidine.

    Science.gov (United States)

    Li, Weilan; Liu, Hongyan; Xu, Qiong

    2012-07-01

    Enterococcus faecalis is frequently recovered from root-filled teeth with refractory apical periodontitis. The ability of E. faecalis to form a matrix-encased biofilm contributes to its pathogenicity; however, the role of extracellular dextran and DNA in biofilm formation and its effect on the susceptibility of the biofilm to chlorhexidine remains poorly understood. E. faecalis biofilms were incubated on dentin blocks. The effect of a dextran-degrading enzyme (dextranase) and DNase I on the adhesion of E. faecalis to dentin was measured using the colony-forming unit (CFU) counting method. CFU assays and confocal laser scanning microscopy were used to investigate the influence of dextranase and DNase I on the antimicrobial activity of 2% chlorhexidine. The CFU count assays indicated that the formation of biofilms by E. faecalis was reduced in cells treated with dextranase or DNase I compared with that in untreated cells (P biofilms with dextranase or DNase I effectively sensitized the biofilms to 2% chlorhexidine (P biofilms to 2% chlorhexidine. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  14. Synthesis, Characterization, and In Vitro and In Vivo Evaluations of 4-(N-Docosahexaenoyl 2′, 2′-Difluorodeoxycytidine with Potent and Broad-Spectrum Antitumor Activity

    Directory of Open Access Journals (Sweden)

    Youssef W. Naguib

    2016-01-01

    Full Text Available In this study, a new compound, 4-(N-docosahexaenoyl 2′, 2′-difluorodeoxycytidine (DHA-dFdC, was synthesized and characterized. Its antitumor activity was evaluated in cell culture and in mouse models of pancreatic cancer. DHA-dFdC is a poorly soluble, pale yellow waxy solid, with a molecular mass of 573.3 Da and a melting point of about 96°C. The activation energy for the degradation of DHA-dFdC in an aqueous Tween 80–based solution is 12.86 kcal/mol, whereas its stability is significantly higher in the presence of vitamin E. NCI-60 DTP Human Tumor Cell Line Screening revealed that DHA-dFdC has potent and broad-spectrum antitumor activity, especially in leukemia, renal, and central nervous system cancer cell lines. In human and murine pancreatic cancer cell lines, the IC50 value of DHA-dFdC was up to 105-fold lower than that of dFdC. The elimination of DHA-dFdC in mouse plasma appeared to follow a biexponential model, with a terminal phase t1/2 of about 58 minutes. DHA-dFdC significantly extended the survival of genetically engineered mice that spontaneously develop pancreatic ductal adenocarcinoma. In nude mice with subcutaneously implanted human Panc-1 pancreatic tumors, the antitumor activity of DHA-dFdC was significantly stronger than the molar equivalent of dFdC alone, DHA alone, or the physical mixture of them (1:1, molar ratio. DHA-dFdC also significantly inhibited the growth of Panc-1 tumors orthotopically implanted in the pancreas of nude mice, whereas the molar equivalent dose of dFdC alone did not show any significant activity. DHA-dFdC is a promising compound for the potential treatment of cancers in organs such as the pancreas.

  15. Detection and characterization of broad-spectrum antipathogen activity of novel rhizobacterial isolates and suppression of Fusarium crown and root rot disease of tomato.

    Science.gov (United States)

    Zhang, L; Khabbaz, S E; Wang, A; Li, H; Abbasi, P A

    2015-03-01

    To detect and characterize broad-spectrum antipathogen activity of indigenous bacterial isolates obtained from potato soil and soya bean leaves for their potential to be developed as biofungicides to control soilborne diseases such as Fusarium crown and root rot of tomato (FCRR) caused by Fusarium oxysporum f. sp. radicis-lycopersici (Forl). Thirteen bacterial isolates (Bacillus amyloliquefaciens (four isolates), Paenibacillus polymyxa (three isolates), Pseudomonas chlororaphis (two isolates), Pseudomonas fluorescens (two isolates), Bacillus subtilis (one isolate) and Pseudomonas sp. (one isolate)) or their volatiles showed antagonistic activity against most of the 10 plant pathogens in plate assays. Cell-free culture filtrates (CF) of five isolates or 1-butanol extracts of CFs also inhibited the growth of most pathogen mycelia in plate assays. PCR analysis confirmed the presence of most antibiotic biosynthetic genes such as phlD, phzFA, prnD and pltC in most Pseudomonas isolates and bmyB, bacA, ituD, srfAA and fenD in most Bacillus isolates. These bacterial isolates varied in the production of hydrogen cyanide (HCN), siderophores, β-1,3-glucanases, chitinases, proteases, indole-3-acetic acid, salicylic acid, and for nitrogen fixation and phosphate solubilization. Gas chromatography-mass spectrometry analysis identified 10 volatile compounds from 10 isolates and 18 compounds from 1-butanol extracts of CFs of five isolates. Application of irradiated peat formulation of six isolates to tomato roots prior to transplanting in a Forl-infested potting mix and field soil provided protection of tomato plants from FCRR disease and enhanced plant growth under greenhouse conditions. Five of the 13 indigenous bacterial isolates were antagonistic to eight plant pathogens, both in vitro and in vivo. Antagonistic and plant-growth promotion activities of these isolates might be related to the production of several types of antibiotics, lytic enzymes, phytohormones, secondary

  16. Interaction between chlorhexidine digluconate and sodium monofluorophosphate in vitro

    International Nuclear Information System (INIS)

    Barkvoll, P.; Roella, G.; Bellagamba, S.

    1988-01-01

    The aim of the present study was to investigate the compatibility of chlorhexidine digluconate and sodium monofluorophosphate since these agents are potential ingredients in future products in preventive dentistry. Varying combinations of chlorhexidine digluconate and sodium monofluorophosphate in water, covering the possible ranges of clinically relevant concentrations of both compounds, were made, incubated for 24 h and observed for precipitation of insoluble salts. The mixtures were analyzed for presence of free chlorhexidine and monofluorophosphate after incubation. The results showed that chlorhexidine digluconate and sodium monofluorophosphate are not compatible in clinically relevant concentrations. A chlorhexidinemonofluorophosphate salt of low solubility in water is presumably formed. (author)

  17. New intracanal formulations containing doxycycline or chlorhexidine against Enterococcus faecalis.

    Science.gov (United States)

    Silva, Ana Rita Marques da; Pinto, Shelon Cristina Souza; Santos, Elizabete Brasil dos; Santos, Fábio André dos; Farago, Paulo Vitor; Gomes, João Carlos; Pina-Vaz, Irene; Carvalho, Manuel Fontes

    2014-01-01

    The present study aims to evaluate the antimicrobial effect of two new intracanal preparations against E. faecalis. Thirty single-rooted human canine teeth were used. The crowns were removed and the roots were instrumented using a conventional technique. Three groups of ten teeth each were infected with 108 CFU/ ml of E. faecalis for 21 days. The root canals were flled with new intracanal medications containing 3% doxycycline hydrochloride (DX) or 2% chlorhexidine digluconate (CHX). Ten teeth received no medication (NM)-negative control. Microbial samples were obtained 21 days after contamination: 14 days under the effect of the intracanal medications and 7 days after replacing the medications by BHI broth. The samples were homogenized, diluted, seeded on BHI agar and incubated for 48h/36°C. The number of colony forming units (CFU/ml) was obtained and analyzed statistically. All intracanal dressings significantly reduced the number of bacterial cells in the root canal after 14 days with medication. After the period with 7 days with BHI broth, the CFU counts of E. faecalis remained at low values. However, the NM group showed a significant increase of CFU in this period to similar values of the initial contamination. 3% doxycycline hydrochloride gel and 2% CHX gel were effective to eliminate E. faecalis from the root canal system.

  18. Antiseptic Effect of Conventional Povidone-Iodine Scrub, Chlorhexidine Scrub, and Waterless Hand Rub in a Surgical Room: A Randomized Controlled Trial.

    Science.gov (United States)

    Tsai, Jui-Chen; Lin, Yen-Kuang; Huang, Yen-Jung; Loh, El-Wui; Wen, Hsiao-Yun; Wang, Chia-Hui; Tsai, Yin-Tai; Hsieh, Wen-Shyang; Tam, Ka-Wai

    2017-04-01

    OBJECTIVE Effective perioperative hand antisepsis is crucial for the safety of patients and medical staff in surgical rooms. The antimicrobial effectiveness of different antiseptic methods, including conventional hand scrubs and waterless hand rubs, has not been well evaluated. DESIGN, SETTING, AND PARTICIPANTS A randomized controlled trial was conducted to investigate the effectiveness of the 3 antiseptic methods among surgical staff of Taipei Medical University-Shuang Ho Hospital. For each method used, a group of 80 participants was enrolled. INTERVENTION Surgical hand cleansing with conventional 10% povidone-iodine scrub, conventional 4% chlorhexidine scrub, or waterless hand rub (1% chlorhexidine gluconate and 61% ethyl alcohol). RESULTS Colony-forming unit (CFU) counts were collected using the hand imprinting method before and after disinfection and after surgery. After surgical hand disinfection, the mean CFU counts of the conventional chlorhexidine (0.5±0.2, Pantiseptic method (P=.0036), but not other variables, predicted the mean CFU count. CONCLUSIONS Conventional chlorhexidine scrub and waterless hand rub were superior to a conventional povidone-iodine product in bacterial inhibition. We recommend using conventional chlorhexidine scrub as a standard method for perioperative hand antisepsis. Waterless hand rub may be used if the higher cost is affordable. Infect Control Hosp Epidemiol 2017;38:417-422.

  19. Agonistic and Antagonistic Interactions between Chlorhexidine and Other Endodontic Agents: A Critical Review.

    Science.gov (United States)

    Mohammadi, Zahed; Giardino, Luciano; Palazzi, Flavio; Asgary, Saeed

    2015-01-01

    Root canal irrigants play a significant role in elimination of the microorganisms, tissue remnants, and removal of the debris and smear layer. No single solution is able to fulfill all these actions completely; therefore, a combination of irrigants may be required. The aim of this investigation was to review the agonistic and antagonistic interactions between chlorhexidine (CHX) and other irrigants and medicaments. An English-limited Medline search was performed for articles published from 2002 to 2014. The searched keywords included: chlorhexidine AND sodium hypochlorite/ethylenediaminetetraacetic acid/calcium hydroxide/mineral trioxide aggregate. Subsequently, a hand search was carried out on the references of result articles to find more matching papers. Findings showed that the combination of CHX and sodium hypochlorite (NaOCl) causes color changes and the formation of a neutral and insoluble precipitate; CHX forms a salt with ethylenediaminetetraacetic acid (EDTA). In addition, it has been demonstrated that the alkalinity of calcium hydroxide (CH) remained unchanged after mixing with CHX. Furthermore, mixing CHX with CH may enhance its antimicrobial activity; also mixing mineral trioxide aggregate (MTA) powder with CHX increases its antimicrobial activity but this may negatively affect its mechanical properties.

  20. A Sequential Statistical Approach towards an Optimized Production of a Broad Spectrum Bacteriocin Substance from a Soil Bacterium Bacillus sp. YAS 1 Strain

    Directory of Open Access Journals (Sweden)

    Amira M. Embaby

    2014-01-01

    Full Text Available Bacteriocins, ribosomally synthesized antimicrobial peptides, display potential applications in agriculture, medicine, and industry. The present study highlights integral statistical optimization and partial characterization of a bacteriocin substance from a soil bacterium taxonomically affiliated as Bacillus sp. YAS 1 after biochemical and molecular identifications. A sequential statistical approach (Plackett-Burman and Box-Behnken was employed to optimize bacteriocin (BAC YAS 1 production. Using optimal levels of three key determinants (yeast extract (0.48% (w/v, incubation time (62 hrs, and agitation speed (207 rpm in peptone yeast beef based production medium resulted in 1.6-fold enhancement in BAC YAS 1 level (470 AU/mL arbitrary units against Erwinia amylovora. BAC YAS 1 showed activity over a wide range of pH (1–13 and temperature (45–80°C. A wide spectrum antimicrobial activity of BAC YAS 1 against the human pathogens (Clostridium perfringens, Staphylococcus epidermidis, Campylobacter jejuni, Enterobacter aerogenes, Enterococcus sp., Proteus sp., Klebsiella sp., and Salmonella typhimurium, the plant pathogen (E. amylovora, and the food spoiler (Listeria innocua was demonstrated. On top and above, BAC YAS 1 showed no antimicrobial activity towards lactic acid bacteria (Lactobacillus bulgaricus, L. casei, L. lactis, and L. reuteri. Promising characteristics of BAC YAS 1 prompt its commercialization for efficient utilization in several industries.

  1. Molecular Design, Structures, and Activity of Antimicrobial Peptide-Mimetic Polymers

    Science.gov (United States)

    Takahashi, Haruko; Palermo, Edmund F.; Yasuhara, Kazuma; Caputo, Gregory A.

    2014-01-01

    There is an urgent need for new antibiotics which are effective against drug-resistant bacteria without contributing to resistance development. We have designed and developed antimicrobial copolymers with cationic amphiphilic structures based on the mimicry of naturally occurring antimicrobial peptides. These copolymers exhibit potent antimicrobial activity against a broad spectrum of bacteria including methicillin-resistant Staphylococcus aureus with no adverse hemolytic activity. Notably, these polymers also did not result in any measurable resistance development in E. coli. The peptide-mimetic design principle offers significant flexibility and diversity in the creation of new antimicrobial materials and their potential biomedical applications. PMID:23832766

  2. In Vivo, In Vitro, and In Silico Characterization of Peptoids as Antimicrobial Agents

    DEFF Research Database (Denmark)

    Czyzewski, Ann M.; Jenssen, Håvard; Fjell, Christopher D.

    2016-01-01

    report a new QSAR model that we developed based on 27 diverse peptoid sequences, which accurately correlates antimicrobial peptoid structure with antimicrobial activity. We have identified a number of peptoids that have potent, broad-spectrum in vitro activity against multi-drug resistant bacterial......Bacterial resistance to conventional antibiotics is a global threat that has spurred the development of antimicrobial peptides (AMPs) and their mimetics as novel anti-infective agents. While the bioavailability of AMPs is often reduced due to protease activity, the non-natural structure of AMP...... potential of peptoids as antimicrobial agents....

  3. Resistance of Streptococcus sanguis biofilms to antimicrobial agents

    DEFF Research Database (Denmark)

    Larsen, T; Fiehn, N E

    1996-01-01

    of Streptococcus sanguis 804 and ATCC 10556 to amoxicillin, doxycycline and chlorhexidine was determined by a broth dilution method. Subsequently, S. sanguis biofilms established in an in vitro flow model were perfused with the antimicrobial agents for 48 h at concentrations equal to and up to 500 times the MIC...

  4. Antimicrobial Peptides for Therapeutic Applications: A Review

    Directory of Open Access Journals (Sweden)

    Tsogbadrakh Mishig-Ochir

    2012-10-01

    Full Text Available Antimicrobial peptides (AMPs have been considered as potential therapeutic sources of future antibiotics because of their broad-spectrum activities and different mechanisms of action compared to conventional antibiotics. Although AMPs possess considerable benefits as new generation antibiotics, their clinical and commercial development still have some limitations, such as potential toxicity, susceptibility to proteases, and high cost of peptide production. In order to overcome those obstacles, extensive efforts have been carried out. For instance, unusual amino acids or peptido-mimetics are introduced to avoid the proteolytic degradation and the design of short peptides retaining antimicrobial activities is proposed as a solution for the cost issue. In this review, we focus on small peptides, especially those with less than twelve amino acids, and provide an overview of the relationships between their three-dimensional structures and antimicrobial activities. The efforts to develop highly active AMPs with shorter sequences are also described.

  5. Antimicrobial properties of Honduran medicinal plants.

    Science.gov (United States)

    Lentz, D L; Clark, A M; Hufford, C D; Meurer-Grimes, B; Passreiter, C M; Cordero, J; Ibrahimi, O; Okunade, A L

    1998-12-01

    Ninety-two plants used in the traditional pharmacopoeia of the Pech and neighboring Mestizo peoples of central Honduras are reported. The results of in vitro antimicrobial screens showed that 19 of the extracts from medicinal plants revealed signs of antifungal activity while 22 demonstrated a measurable inhibitory effect on one or more bacterial cultures. Bioassay-guided fractionation of extracts from Mikania micrantha, Neurolaena lobata and Piper aduncum produced weak to moderately active isolates. The broad spectrum of activity of the extracts helps to explain the widespread use of these plants for wound healing and other applications.

  6. Evaluation of Antimicrobial Activity of Root Extracts of Abitulon indicum

    Directory of Open Access Journals (Sweden)

    Krishna Rao MORTHA

    2015-06-01

    Full Text Available Antimicrobial activity of Abitulon indicum roots was studied against seven pathogenic bacteria and three fungal strains by agar well diffusion method. Antimicrobial activity was recorded for hexane, chloroform, methanol, ethanol and aqueous extracts. Alcohol (ethanol and methanol extracts exhibited the highest degree of antimicrobial activity compared to aqueous, chloroform and hexane extracts. Pseudomonas aeruginosa was turned out to be the most susceptible bacterium to the crude root chemical constituents, using the standard Tetracycline and Clotrimazole. Minimum inhibition concentration values of hexane, chloroform, methanol, ethanol and aqueous extracts were determined by the agar dilution method and ranged between 62.5 and 1,000 µg. The study suggested that the root extracts possess bioactive compounds with antimicrobial activity against the tested bacteria and fungi, revealing a significant scope to develop a novel broad spectrum of antimicrobial drug formulation from Abitulon indicum.

  7. Gold Nanoparticle Conjugation Enhances the Antiacanthamoebic Effects of Chlorhexidine

    Science.gov (United States)

    Aqeel, Yousuf; Siddiqui, Ruqaiyyah; Anwar, Ayaz; Shah, Muhammad Raza

    2015-01-01

    Acanthamoeba keratitis is a serious infection with blinding consequences and often associated with contact lens wear. Early diagnosis, followed by aggressive topical application of drugs, is a prerequisite in successful treatment, but even then prognosis remains poor. Several drugs have shown promise, including chlorhexidine gluconate; however, host cell toxicity at physiologically relevant concentrations remains a challenge. Nanoparticles, subcolloidal structures ranging in size from 10 to 100 nm, are effective drug carriers for enhancing drug potency. The overall aim of the present study was to determine whether conjugation with gold nanoparticles enhances the antiacanthamoebic potential of chlorhexidine. Gold-conjugated chlorhexidine nanoparticles were synthesized. Briefly, gold solution was mixed with chlorhexidine and reduced by adding sodium borohydride, resulting in an intense deep red color, indicative of colloidal gold-conjugated chlorhexidine nanoparticles. The synthesis was confirmed using UV-visible spectrophotometry that shows a plasmon resonance peak of 500 to 550 nm, indicative of gold nanoparticles. Further characterization using matrix-assisted laser desorption ionization-mass spectrometry showed a gold-conjugated chlorhexidine complex at m/z 699 ranging in size from 20 to 100 nm, as determined using atomic force microscopy. To determine the amoebicidal and amoebistatic effects, amoebae were incubated with gold-conjugated chlorhexidine nanoparticles. For controls, amoebae also were incubated with gold and silver nanoparticles alone, chlorhexidine alone, neomycin-conjugated nanoparticles, and neomycin alone. The findings showed that gold-conjugated chlorhexidine nanoparticles exhibited significant amoebicidal and amoebistatic effects at 5 μM. Amoebicidal effects were observed by parasite viability testing using a Trypan blue exclusion assay and flow-cytometric analysis using propidium iodide, while amoebistatic effects were observed using growth

  8. Antibacterial effect of triantibiotic mixture, chlorhexidine gel, and two natural materials Propolis and Aloe vera against Enterococcus faecalis: An ex vivo study

    OpenAIRE

    Bazvand, Leila; Aminozarbian, Mohammad Ghasem; Farhad, Alireza; Noormohammadi, Hamid; Hasheminia, Seyed Mohsen; Mobasherizadeh, Sina

    2014-01-01

    Background: The aim of this ex vivo study was to compare the antimicrobial effect of triantibiotic paste, 0.2% chlorhexidine gel, Propolis and Aloe vera on Enterococcus faecalis in deep dentin. Materials and Methods: Ninety fresh extracted single-rooted teeth were used in a dentin block model. Seventy-five teeth were infected with E. faecalis and divided into four experimental groups (n = 15). Experimental groups were treated with triantibiotic mixture with distilled water, 0.2% chlorhexi...

  9. Anaphylactic reactions in anaesthetised patients - four cases of chlorhexidine allergy

    DEFF Research Database (Denmark)

    Garvey, L H; Roed-Petersen, J; Husum, B

    2001-01-01

    Chlorhexidine is widely used all over the world in many different preparations. In Denmark chlorhexidine is the standard skin disinfectant used before surgery or invasive procedures and it is widely used in the general population in mouthwash or for disinfection of minor scratches etc. The potent......Chlorhexidine is widely used all over the world in many different preparations. In Denmark chlorhexidine is the standard skin disinfectant used before surgery or invasive procedures and it is widely used in the general population in mouthwash or for disinfection of minor scratches etc....... The potential for developing allergy to chlorhexidine is thus great, especially in surgical patients. We have identified four patients with serious allergic reactions in connection with surgery and general anaesthesia, who on subsequent skin testing tested positive for chlorhexidine. Symptoms appeared 20-40 min...... into the operation and all four patients required treatment with adrenaline. All four patients had a history of minor symptoms like rashes or faints in connection with previous surgery/invasive procedures. Allergy to chlorhexidine may be more prevalent in surgical patients and cases may have been overlooked due...

  10. Helical Antimicrobial Sulfono- {gamma} -AApeptides

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-06-11

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

  11. Genome-Wide Identification of Antimicrobial Intrinsic Resistance Determinants in Staphylococcus aureus

    DEFF Research Database (Denmark)

    Vestergaard, Martin; Leng, Bingfeng; Haaber, Jakob

    2016-01-01

    The emergence of antimicrobial resistance severely threatens our ability to treat bacterial infections. While acquired resistance has received considerable attention, relatively little is known of intrinsic resistance that allows bacteria to naturally withstand antimicrobials. Gene products...... that confer intrinsic resistance to antimicrobial agents may be explored for alternative antimicrobial therapies, by potentiating the efficacy of existing antimicrobials. In this study, we identified the intrinsic resistome to a broad spectrum of antimicrobials in the human pathogen, Staphylococcus aureus. We...... with the atpA mutant compared to wild type cells with gentamicin at a clinically relevant concentration. Our results demonstrate that many gene products contribute to the intrinsic antimicrobial resistance of S. aureus. Knowledge of these intrinsic resistance determinants provides alternative targets...

  12. Effect of fluoride and chlorhexidine digluconate mouthrinses on plaque biofilms.

    Science.gov (United States)

    Rabe, Per; Twetman, Svante; Kinnby, Bertil; Svensäter, Gunnel; Davies, Julia R

    2015-01-01

    To develop a model in which to investigate the architecture of plaque biofilms formed on enamel surfaces in vivo and to compare the effects of anti-microbial agents of relevance for caries on biofilm vitality. Materials and Methodology : Enamel discs mounted on healing abutments in the pre-molar region were worn by three subjects for 7 days. Control discs were removed before subjects rinsed with 0.1% chlorhexidine digluconate (CHX) or 0.2% sodium fluoride (NaF) for 1 minute. Biofilms were stained with Baclight Live/Dead and z-stacks of images created using confocal scanning laser micoscopy. The levels of vital and dead/damaged bacteria in the biofilms, assessed as the proportion of green and red pixels respectively, were analysed using ImageTrak(®) software. Results : The subjects showed individual differences in biofilm architecture. The thickness of the biofilms varied from 28-96µm although cell density was always the greatest in the middle layers. In control biofilms, the overall levels of vitality were high (71-98%) especially in the area closest to the enamel interface. Rinsing with either CHX or NaF caused a similar reduction in overall vitality. CHX exerted an effect throughout the biofilm, particularly on the surface of cell clusters whereas NaF caused cell damage/death mainly in the middle to lower biofilm layers. Conclusion : We describe a model that allows the formation of mature, undisturbed oral biofilms on human enamel surfaces in vivo and show that CHX and NaF have a similar effect on overall vitality but differ in their sites of action.

  13. Antimicrobial effectiveness of Neem (Azadirachta indica and Babool (Acacia nilotica on Streptococcus mutans: An in vitro study

    Directory of Open Access Journals (Sweden)

    R Pandya Sajankumar

    2015-01-01

    Full Text Available Introduction: There is an exponential growth in the field of herbal medicine because of their natural origin, easy availability, efficacy, and safety. Aim: To compare the antimicrobial effectiveness of Neem and Babool on Streptococcus mutans. Materials and Methods: An in vitro study was conducted to compare the effectiveness of 5%, 10%, and 50% of Neem and Babool aqueous extract with 5%, 10%, and 50% of 0.2% chlorhexidine mouthwash on S. mutans. The ditch plate method was used to test the antimicrobial activity. Ditches were prepared on blood agar plates with the help of punch having 7 mm diameter. The plates were left for 1 h at room temperature and then incubated at 37°C for 48 h and examined for zone of inhibition. Results: Inhibitory effect of 5% Neem is significantly better than 5% Babool and 5% chlorhexidine mouthwash (P < 0.05. At 10% and 50%, Neem and Babool are significantly better than chlorhexidine mouthwash (P < 0.05. Inhibitory effect of Babool increases as the concentration increases (P < 0.05. The inhibitory effect of 5% and 50% chlorhexidine mouthwash is better than 10% chlorhexidine mouthwash (P < 0.05. Conclusion: Aqueous extract of Neem exhibited the highest antimicrobial activity compared with Babool and chlorhexidine mouthwash.

  14. Contamination of chlorhexidine cream used to prevent ascending urinary tract infections

    Energy Technology Data Exchange (ETDEWEB)

    Salveson, A.; Bergan, T.

    1981-06-01

    Chlorhexidine-containing cream is often used as an antimicrobial barrier to ascending urinary tract infection in patients with indwelling urethral catheters. The cream is dispensed in small tubes for personal use but repeated use of a tube still entails a potential infection hazard. The extent of cream contamination was analysed by emulsifying it in 1% peptone broth with 1% Tween-80 added as a wetting agent, and culturing quantitatively for bacteria and fungi by membrane filtration. Twenty-three per cent of cream samples and 35% of swabs taken from outside the tube beneath the screw cap demonstrated microbial contamination. Isolates included potential pathogens such as enterococci, staphylococci, Proteus mirabilis, Pseudomonas aeruginosa, opportunists like Moraxella spp. and diphtheroids, and contaminants such as Bacillus spp., micrococci, and a mould of the genus Cladosporium. Contamination of cream with a particular bacterial strain was found to precede urinary tract infection with the same microbe. We recommend that chlorhexidine cream for this use be dispensed in single dose units to ensure sterility.

  15. Antimicrobial Peptide Production and Purification.

    Science.gov (United States)

    Suda, Srinivas; Field, Des; Barron, Niall

    2017-01-01

    Antimicrobial peptides (AMPs) are natural defense compounds which are synthesized as ribosomal gene-encoded pre-peptides and produced by all living organisms. AMPs are small peptides, usually cationic and typically have hydrophobic residues which interact with cell membranes and have either a narrow or broad spectrum of biological activity. AMPs are isolated from the natural host or heterologously expressed in other hosts such as Escherichia coli. The proto-typical lantibiotic Nisin is a widely used AMP that is produced by the food-grade organism Lactococcus lactis. Although AMP production and purification procedures require optimization for individual AMPs, the Nisin production and purification protocol outlined in this chapter can be easily applied with minor modifications for the production and purification of other lantibiotics or AMPs. While Nisin is produced and secreted into the supernatant, steps to recover Nisin from both cell-free supernatant and cell pellet are outlined in detail.

  16. MRJP1-containing glycoproteins isolated from honey, a novel antibacterial drug candidate with broad spectrum activity against multi-drug resistant clinical isolates

    Directory of Open Access Journals (Sweden)

    Katrina eBrudzynski

    2015-07-01

    Full Text Available The emergence of extended- spectrum β-lactamase (ESBL is the underlying cause of growing antibiotic resistance among Gram-negative bacteria to β-lactam antibiotics. We recently reported the discovery of honey glycoproteins (glps that exhibited a rapid, concentration-dependent antibacterial activity against both Gram-positive Bacillus subtilis and Gram-negative Escherichia coli that resembled action of cell wall-active β-lactam drugs. Glps showed sequence identity with the Major Royal Jelly Protein 1 (MRJP1 precursor that harbors three antimicrobial peptides: Jelleins 1, 2 and 4. Here, we used semi-quantitative radial diffusion assay and broth microdilution assay to evaluate susceptibility of a number of multi-drug resistant (MDR clinical isolates to the MRJP1-contaning honey glycoproteins. The MDR bacterial strains comprised 3 MRSA, 4 Pseudomonas aeruginosa, 2 Klebsiella pneumoniae, 2 VRE and 5 Extended-spectrum beta-lactamase (ESBL identified as 1 Proteus mirabilis, 3 Escherichia coli and 1 Escherichia coli NDM. Their resistance to different classes of antibiotics was confirmed using automated system Vitek 2. MDR isolates differred in their susceptibility to glps with MIC90 values ranging from 4.8μg/ml against B. subtilis to 14.4μg/ml against ESBL K. pneumoniae, Klebsiella spp ESBL and E. coli and up to 33μg/ml against highly resistant strains of P. aeruginosa. Glps isolated from different honeys showed a similar ability to overcome bacterial resistance to β-lactams suggesting that (a their mode of action is distinct from other classes of β-lactams and that (b the common glps structure was the lead structure responsible for the activity. The results of the current study together with our previous evidence of a rapid bactericidal activity of glps demonstrate that glps possess suitable characteristics to be considered a novel antibacterial drug candidate.

  17. Effect of chlorhexidine on bonding durability of two self-etching adhesives with and without antibacterial agent to dentin

    Directory of Open Access Journals (Sweden)

    Fereshteh Shafiei

    2013-01-01

    Conclusion: Chlorhexidine was capable of diminishing the loss of BS of these adhesives over time. However, considering the negative effect of chlorhexidine on the initial BS, the benefits of chlorhexidine associated with these adhesives cannot possibly be used.

  18. Is there a risk of sensitization and allergy to chlorhexidine in health care workers?

    DEFF Research Database (Denmark)

    Garvey, L H; Roed-Petersen, J; Husum, B

    2003-01-01

    BACKGROUND: In Denmark, chlorhexidine is the standard disinfectant in most hospitals and health care workers are repeatedly exposed to it. The aim of this study was to establish whether there is a risk of sensitization and allergy to chlorhexidine from this type of exposure. METHODS: Two hundred...... to examine the risk of type I and type IV allergy to chlorhexidine in health care workers with daily exposure to chlorhexidine, we did not identify allergies to chlorhexidine in any of the 104 individuals tested or in the additional 74 individuals who completed the questionnaire. We conclude that an allergy...... to chlorhexidine in health care workers is likely to be rare....

  19. The effects of daily chlorhexidine bathing on cutaneous bacterial isolates: a pilot study

    Directory of Open Access Journals (Sweden)

    Soma VL

    2012-04-01

    Full Text Available Vijaya L Soma1, Xuan Qin2, Chuan Zhou1, Amanda Adler1, Jessica E Berry2, Danielle M Zerr11Department of Pediatrics, 2Department of Laboratory Medicine, University of Washington, Seattle, WA, USAAbstract: Chlorhexidine gluconate (CHG is a topical antiseptic used in a myriad of clinical settings. Recently, CHG baths have been shown to decrease multidrug-resistant organism acquisition and infections and catheter-associated bloodstream infections. The present study examined the effects of daily bathing with CHG on the recovery and antimicrobial susceptibility of cultivable cutaneous bacteria. The objectives of this study were to (1 explore the effects of clinical CHG bathing on cultivable cutaneous bacteria, (2 study the relationship between CHG minimum inhibitory concentration and antimicrobial susceptibility of coagulase-negative staphylococci, and (3 demonstrate the feasibility of the approach so a more definitive study may be performed. Significant decreases in bacterial colony counts and phenotypic diversity occurred with greater CHG exposure. The findings also suggest an inverse relationship between CHG minimum inhibitory concentration and antimicrobial susceptibility. Larger prospective studies are necessary to fully investigate the clinical impact of CHG usage.Keywords: antiseptic, resistance, Staphylococcus, coagulase-negative

  20. Nisin and its Antimicrobial Effect in Foods

    Directory of Open Access Journals (Sweden)

    Hamparsun Hampikyan

    2007-04-01

    Full Text Available Nisin is a bacteriocin which is produced by Lactococcus lactis and takes its place in I. class bacteriocins which are known as lantibiotics. Nisin has antimicrobial and bactericidal activity against a broad spectrum of gram positive bacteria and spores of Clostridium spp. and Bacillus spp. According to toxicity studies nisin is considered not toxic to humans. Its first established used was as a preservative in processed cheese products and since than numerous other applications in various foods such as meat and meat products, poultry products, sea products and beverages such as beer, wine have been used safely. In this review, the characteristics of nisin, its usage in food and its antimicrobial effect are considered. [TAF Prev Med Bull 2007; 6(2.000: 142-147

  1. A PEGylated Fibrin-Based Wound Dressing with Antimicrobial and Angiogenic Activity

    Science.gov (United States)

    2011-04-13

    activity SSD–CSM particles were impregnated in polyethylene glycol (PEGylated) fibrin gels. In vitro drug release studies showed that a burst release of...promote revascularization. Silver sulfadiazine (SSD) is a broad spectrum antimicrobial agent that controls yeasts, molds, other types of fungi , and...site is currently thought to be a crucial early event in the tissue regeneration process [23]. We have recently shown that a polyethylene glycol-based

  2. Crystal Structure of the New Investigational Drug Candidate VT-1598 in Complex with Aspergillus fumigatus Sterol 14α-Demethylase Provides Insights into Its Broad-Spectrum Antifungal Activity

    Energy Technology Data Exchange (ETDEWEB)

    Hargrove, Tatiana Y.; Garvey, Edward P.; Hoekstra, William J.; Yates, Christopher M.; Wawrzak, Zdzislaw; Rachakonda, Girish; Villalta, Fernando; Lepesheva, Galina I.

    2017-05-01

    ABSTRACT

    Within the past few decades, the incidence and complexity of human fungal infections have increased, and therefore, the need for safer and more efficient, broad-spectrum antifungal agents is high. In the study described here, we characterized the new tetrazole-based drug candidate VT-1598 as an inhibitor of sterol 14α-demethylase (CYP51B) from the filamentous fungusAspergillus fumigatus. VT-1598 displayed a high affinity of binding to the enzyme in solution (dissociation constant, 13 ± 1 nM) and in the reconstituted enzymatic reaction was revealed to have an inhibitory potency stronger than the potencies of all other simultaneously tested antifungal drugs, including fluconazole, voriconazole, ketoconazole, and posaconazole. The X-ray structure of the VT-1598/A. fumigatusCYP51 complex was determined and depicts the distinctive binding mode of the inhibitor in the enzyme active site, suggesting the molecular basis of the improved drug potency and broad-spectrum antifungal activity. These data show the formation of an optimized hydrogen bond between the phenoxymethyl oxygen of VT-1598 and the imidazole ring nitrogen of His374, the CYP51 residue that is highly conserved across fungal pathogens and fungus specific. Comparative structural analysis ofA. fumigatusCYP51/voriconazole andCandida albicansCYP51/VT-1161 complexes supports the role of H bonding in fungal CYP51/inhibitor complexes and emphasizes the importance of an optimal distance between this interaction and the inhibitor-heme iron interaction. Cellular experiments using twoA. fumigatusstrains (strains 32820 and 1022) displayed a direct

  3. Growing Escherichia coli mutants deficient in riboflavin biosynthesis with non-limiting riboflavin results in sensitization to inactivation by broad-spectrum near-ultraviolet light (320-400 nm)

    International Nuclear Information System (INIS)

    Lloyd, R.E.; Rinkenberger, J.L.; Hug, B.A.; Tuveson, R.W.

    1990-01-01

    Two mutants of Escherichia coli unable to synthesize riboflavin were grown with limiting (2 μg ml -1 ) and non-limiting (10 μg ml -1 ) concentrations of riboflavin. These riboflavin auxotrophs when grown to exponential phase with non-limiting riboflavin are more sensitive to broad spectrum near-ultraviolet light (NUV, 320-400 nm) inactivation than when they are grown with limiting riboflavin. Exponential phase cells of the riboflavin auxotrophs grown with limiting riboflavin are sensitized when irradiated in saline supplemented with riboflavin. This suggests that extracellular riboflavin is important as a NUV sensitizer when intracellular levels of riboflavin are reduced. The concentration of riboflavin in crude extracts from exponentially growing cells correlates well with the sensitivity of these mutants to NUV inactivation. The level of riboflavin supplementation has little effect on the NUV sensitivity of the parental strain. (author)

  4. Recolonization of mutans Streptococci after application of chlorhexidine gel.

    Science.gov (United States)

    Vale, Glauber Campos; Cury, Altair Antoninha Del Bel; Arthur, Rodrigo Alex; Cury, Jaime Aparecido; Tabchoury, Cínthia Pereira Machado

    2014-01-01

    Streptococcus mutans is specifically suppressed by intensive treatment with chlorhexidine gel, but the time for recolonization and the effect on other oral bacteria are not totally clear. In this study, recolonization of mutans streptococci was evaluated in nine healthy adult volunteers, who were highly colonized with this microorganism. Stimulated saliva was collected before (baseline) and at 1, 7, 14, 21 and 28 days after application of 1% chlorhexidine gel on volunteers' teeth for two consecutive days. On each day, the gel was applied using disposable trays for 3 x 5 min with intervals of 5 min between each application. Saliva was plated on blood agar to determine total microorganisms (TM); on mitis salivarius agar to determine total streptococci (TS) and on mitis salivarius agar plus bacitracin to determine mutans streptococci (MS). Chlorhexidine was capable of reducing the counts of MS and the proportion of MS with regard to total microorganisms (%MS/TM) (p0.05) after 14 days for MS and 21 days for %MS/TM. The counts of TM and TS and the proportion of MS to total streptococci did not differ statistically from baseline (p>0.05) after chlorhexidine treatment. The results suggest that the effect of chlorhexidine gel treatment on suppression of mutans streptococci is limited to less than a month in highly colonized individuals.

  5. Contact allergy to chlorhexidine in a tertiary dermatology clinic in Denmark

    DEFF Research Database (Denmark)

    Opstrup, Morten S; Johansen, Jeanne D; Zachariae, Claus

    2016-01-01

    cause the contact allergy, and whether accidental re-exposure occurs in some patients. OBJECTIVES: To estimate the prevalence of chlorhexidine contact allergy in a tertiary dermatology clinic in Denmark; to investigate whether patch testing with both chlorhexidine diacetate and chlorhexidine digluconate...

  6. Chlorhexidine controlled-release profile after EDTA root surface etching: an in vivo study.

    Science.gov (United States)

    Gamal, Ahmed Y; Kumper, Radi M; Sadek, Hesham S; El Destawy, Mahmoud T

    2011-05-01

    The main objective of the present study was to quantify chlorhexidine (CHX) release after the use of CHX-EDTA root surface treatment as a local-delivery antimicrobial vehicle. Twenty non-smoking patients clinically diagnosed as having moderate-to-severe chronic periodontitis were selected to participate in this study. After cause-related therapy, one site in every patient received defect overfill with CHX gel 2% (20 sites). In addition, twenty contralateral sites received defect fill of CHX gel after 3 minutes of 24% EDTA gel root surface etching (20 sites). Gingival crevicular fluid samples were collected at 1, 3, 7, and 14 days post-therapy. The CHX-EDTA group showed statistically significantly higher levels of CHX than those of the control group at 1, 3, and 7 days. At 14 days, the CHX-EDTA group showed 0.8 mg/mL values. The use of CHX-EDTA root surface treatment as a local-delivery antimicrobial improves CHX substantivity.

  7. Evaluation of the substantivity in saliva of different forms of application of chlorhexidine.

    Science.gov (United States)

    García-Caballero, Lucia; Carmona, Inmaculada Tomás; González, M Consuelo Cousido; Posse, Jacobo Limeres; Taboada, Jose Llovo; Dios, Pedro Diz

    2009-02-01

    To evaluate the in vivo antimicrobial activity of different forms of application of chlorhexidine digluconate (CHX). A group of 10 volunteers performed mouth rinsings with a 0.2% and 0.12% solution of CHX and applied CHX in the form of a 0.2% gel, a 0.2% and a 0.12% spray and a swab impregnated with a 0.2% solution. Samples of saliva were taken at baseline; 30 seconds; and 1, 3, 5, and 7 hours after each application. An epifluorescence microscopy technique (BacLight Live/Dead stain) was used to evaluate bacterial vitality. Bacterial vitality under basal conditions was 92%. At 30 seconds after CHX application, the lowest levels of viable bacteria were detected with the 0.2% and 0.12% solutions (1% and 8%, respectively). After 3 hours, the percentage of live bacteria achieved with the gel and sprays was similar to the basal figures (80% to 91%). At 7 hours, bacterial vitality recovered basal percentages, except with the 0.2% solution (77%). The 0.2% solution of CHX had the greatest sustained antimicrobial effect on the salivary flora, confirming the influence of the concentration and form of application on CHX substantivity.

  8. Broad-spectrum antiviral properties of andrographolide.

    Science.gov (United States)

    Gupta, Swati; Mishra, K P; Ganju, Lilly

    2017-03-01

    Andrographolide, a diterpenoid, is known for its anti-inflammatory effects. It can be isolated from various plants of the genus Andrographis, commonly known as 'creat'. This purified compound has been tested for its anti-inflammatory effects in various stressful conditions, such as ischemia, pyrogenesis, arthritis, hepatic or neural toxicity, carcinoma, and oxidative stress, Apart from its anti-inflammatory effects, andrographolide also exhibits immunomodulatory effects by effectively enhancing cytotoxic T cells, natural killer (NK) cells, phagocytosis, and antibody-dependent cell-mediated cytotoxicity (ADCC). All these properties of andrographolide form the foundation for the use of this miraculous compound to restrain virus replication and virus-induced pathogenesis. The present article covers antiviral properties of andrographolide in variety of viral infections, with the hope of developing of a new highly potent antiviral drug with multiple effects.

  9. Declines in Outpatient Antimicrobial Use in Canada (1995–2010)

    Science.gov (United States)

    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

  10. Cationic compounds with activity against multidrug-resistant bacteria: interest of a new compound compared with two older antiseptics, hexamidine and chlorhexidine.

    Science.gov (United States)

    Grare, M; Dibama, H Massimba; Lafosse, S; Ribon, A; Mourer, M; Regnouf-de-Vains, J-B; Finance, C; Duval, R E

    2010-05-01

    Use of antiseptics and disinfectants is essential in infection control practices in hospital and other healthcare settings. In this study, the in vitro activity of a new promising compound, para-guanidinoethylcalix[4]arene (Cx1), has been evaluated in comparison with hexamidine (HX) and chlorhexidine (CHX), two older cationic antiseptics. The MICs for 69 clinical isolates comprising methicillin-resistant Staphylococcus aureus, methicillin-sensitive S. aureus, coagulase-negative staphylococci (CoNS) (with or without mecA), vancomycin-resistant enterococci, Enterobacteriaceae producing various beta-lactamases and non-fermenting bacilli (Pseudomonas aeruginosa, Acinetobacter baumanii, Stenotrophomonas maltophilia) were determined. Cx1 showed similar activity against S. aureus, CoNS and Enterococcus spp., irrespective of the presence of mecA or van genes, or associated resistance genes, with very good activity against CoNS (MIC compound against all strains, with broad-spectrum and conserved activity against multidrug-resistant strains. HX showed a lower activity, essentially against Gram-positive strains. Consequently, the differences observed with respect to Cx1 suggest that they are certainly not the consequence of antibiotic resistance phenotypes, but rather the result of membrane composition modifications (e.g. of lipopolysaccharide), or of the presence of (activated) efflux-pumps. These results raise the possibility that Cx1 may be a potent new antibacterial agent of somewhat lower activity but significantly lower toxicity than CHX.

  11. Formulation and evaluation of antimicrobial activity of Morus alba sol-gel against periodontal pathogens

    Directory of Open Access Journals (Sweden)

    Shilpa Gunjal

    2015-01-01

    Full Text Available Background: Periodontitis has a multifactorial etiology, with primary etiologic agents being pathogenic bacteria that reside in the subgingival area. Recent advances in the field of alternative medicine introduced various herbal products for the treatment of periodontitis. Aim: To assess and compare the antimicrobial activity of Morus alba sol-gel with chlorhexidine sol-gel against ATCC standard strains of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Tannerella forsythia. Materials and Methods: Crude extract of Morus alba leaves was prepared by Soxhlet method by using ethanol as a solvent. Phytochemical screening of the crude extract of M. alba was performed to check the various chemical constituents. M. alba sol-gel and chlorhexidine sol-gel were formulated using Pluronic f127 and Pluronic f108 and compared for their antimicrobial activity. The minimum inhibitory concentration of both the gels was performed using agar well diffusion technique. Results: The minimum inhibitory concentration of M. alba sol-gel and chlorhexidine sol-gel against A. actinomycetemcomitans is 19 and 17 mm, T. forsythia is 12 and 21 mm, and P. gingivalis is 16 and 18 mm, respectively. Conclusion: Both M. alba and chlorhexidine sol-gel exhibited potent antimicrobial activity against periodontal pathogens.

  12. Chlorhexidine avoids skin bacteria recolonization more than triclosan.

    Science.gov (United States)

    Macias, Juan H; Alvarez, Mildred F; Arreguin, Virginia; Muñoz, Juan M; Macias, Alejandro E; Alvarez, Jose A

    2016-12-01

    We do not know whether differences exist between the residual effect of 2% chlorhexidine in 70% isopropyl alcohol when compared with 1% triclosan in 70% isopropyl alcohol. Using an analytic, longitudinal, controlled, and comparative experimental trial, with blinded measurements, we recruited healthy, adult volunteers from the University of Guanajuato who completed a stabilization phase of skin microbiota and had no history of skin allergies. Four 25-cm 2 areas of the inner surface of the forearms were designated for study: unscrubbed control for establishing baseline bacterial counts, scrubbed control with tridistilled water, scrubbed with chlorhexidine, and scrubbed with triclosan. Quantitative cultures were taken of all the areas at 0, 3, and 24 hours, using agar plates with neutralizing agents. A total of 135 healthy volunteers were tested. At 24 hours, the unscrubbed control counts were 288 CFU/cm 2 , whereas the scrubbed control counts were 96 CFU/cm 2 ; 24 CFU/cm 2 for chlorhexidine and 96 CFU/cm 2 for triclosan (Kruskal-Wallis χ 2 H = 64.27; P <.001). Chlorhexidine is the best antiseptic option when a prolonged antiseptic effect is needed; for instance, when implanting medical devices or performing surgical procedures. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  13. Investigating the Antimicrobial Bioactivity of Cyano bacterial Extracts on Some Plant and Human Pathogens

    International Nuclear Information System (INIS)

    El-Semary, N.A.; Osman, M.E.; Ahmed, A.S.; Botros, H.W.; Farag, A.T.

    2014-01-01

    The search for broad spectrum antimicrobial agents against microbial pathogens, as the available bioactive compounds, has decreasing efficacy and the multidrug resistance trait is spreading among pathogens. Accordingly, the study was carried out to investigate the antimicrobial bioactivity of extracts derived from a cyano bacterial strain from Egypt. The solvents used were diethyl ether, chloroform and methanol. The antimicrobial bioassay of the lipophilic fraction dissolved in diethyl ether of Synechococcus spp. (isolated from Wadi El-Natroun, Egypt) showed the highest broad spectrum bioactivity as it inhibited the growth of both plant and human pathogens. The extract was also effective on the filamentous plant pathogenic fungi Aspergillus flavus and Aspergillus niger. The effects of incubation periods, growth media and pH values on both growth and antimicrobial activity of Synechococcus spp. were investigated. Chu medium was the medium that gave the highest growth followed by BG11 medium then Oscillatoria medium and all these three media showed antibacterial activities but only BG11 showed both antibacterial and antifungal activities after 18 days of incubation. The pH value 10 proved to be the best for growth and antimicrobial activities of Synechococcus spp. in BG11 medium

  14. A high-resolution map of the Grp1 locus on chromosome V of potato harbouring broad-spectrum resistance to the cyst nematode species Globodera pallida and Globodera rostochiensis.

    Science.gov (United States)

    Finkers-Tomczak, Anna; Danan, Sarah; van Dijk, Thijs; Beyene, Amelework; Bouwman, Liesbeth; Overmars, Hein; van Eck, Herman; Goverse, Aska; Bakker, Jaap; Bakker, Erin

    2009-06-01

    The Grp1 locus confers broad-spectrum resistance to the potato cyst nematode species Globodera pallida and Globodera rostochiensis and is located in the GP21-GP179 interval on the short arm of chromosome V of potato. A high-resolution map has been developed using the diploid mapping population RHAM026, comprising 1,536 genotypes. The flanking markers GP21 and GP179 have been used to screen the 1,536 genotypes for recombination events. Interval mapping of the resistances to G. pallida Pa2 and G. rostochiensis Ro5 resulted in two nearly identical LOD graphs with the highest LOD score just north of marker TG432. Detailed analysis of the 44 recombinant genotypes showed that G. pallida and G. rostochiensis resistance could not be separated and map to the same location between marker SPUD838 and TG432. It is suggested that the quantitative resistance to both nematode species at the Grp1 locus is mediated by one or more tightly linked R genes that might belong to the NBS-LRR class.

  15. Novel, broad-spectrum anticonvulsants containing a sulfamide group: pharmacological properties of (S)-N-[(6-chloro-2,3-dihydrobenzo[1,4]dioxin-2-yl)methyl]sulfamide (JNJ-26489112).

    Science.gov (United States)

    McComsey, David F; Smith-Swintosky, Virginia L; Parker, Michael H; Brenneman, Douglas E; Malatynska, Ewa; White, H Steve; Klein, Brian D; Wilcox, Karen S; Milewski, Michael E; Herb, Mark; Finley, Michael F A; Liu, Yi; Lubin, Mary Lou; Qin, Ning; Reitz, Allen B; Maryanoff, Bruce E

    2013-11-27

    Broad-spectrum anticonvulsants are of considerable interest as antiepileptic drugs, especially because of their potential for treating refractory patients. Such "neurostabilizers" have also been used to treat other neurological disorders, including migraine, bipolar disorder, and neuropathic pain. We synthesized a series of sulfamide derivatives (4-9, 10a-i, 11a, 11b, 12) and evaluated their anticonvulsant activity. Thus, we identified promising sulfamide 4 (JNJ-26489112) and explored its pharmacological properties. Compound 4 exhibited excellent anticonvulsant activity in rodents against audiogenic, electrically induced, and chemically induced seizures. Mechanistically, 4 inhibited voltage-gated Na(+) channels and N-type Ca(2+) channels and was effective as a K(+) channel opener. The anticonvulsant profile of 4 suggests that it may be useful for treating multiple forms of epilepsy (generalized tonic-clonic, complex partial, absence seizures), including refractory (or pharmacoresistant) epilepsy, at dose levels that confer a good safety margin. On the basis of its pharmacology and other favorable characteristics, 4 was advanced into human clinical studies.

  16. Kaposi sarcoma-associated herpes virus targets the lymphotactin receptor with both a broad spectrum antagonist vCCL2 and a highly selective and potent agonist vCCL3

    DEFF Research Database (Denmark)

    Lüttichau, Hans R; Johnsen, Anders H; Jurlander, Jesper

    2007-01-01

    virus (KSHV) encodes three chemokine-like proteins named vCCL1, vCCL2, and vCCL3. In this study vCCL3 was probed in parallel with vCCL1 and vCCL2 against a panel of the 18 classified human chemokine receptors. In calcium mobilization assays vCCL1 acted as a selective CCR8 agonist, whereas vCCL2......Large DNA viruses such as herpesvirus and poxvirus encode proteins that target and exploit the chemokine system of their host. These proteins have the potential to block or change the orchestrated recruitment of leukocytes to sites of viral infection. The genome of Kaposi sarcoma-associated herpes...... was found to act as a broad spectrum chemokine antagonist of human chemokine receptors, including the lymphotactin receptor. In contrast vCCL3 was found to be a highly selective agonist for the human lymphotactin receptor XCR1. The potency of vCCL3 was found to be 10-fold higher than the endogenous human...

  17. Decontamination of stethoscope membranes with chlorhexidine: Should it be recommended?

    Science.gov (United States)

    Álvarez, José A; Ruíz, Susana R; Mosqueda, Juan L; León, Ximena; Arreguín, Virginia; Macías, Alejandro E; Macias, Juan H

    2016-11-01

    To determine differences in the recontamination of stethoscope membranes after cleaning with chlorhexidine, triclosan, or alcohol. Experimental, controlled, blinded trial to determine differences in the bacterial load on stethoscope membranes. Membranes were cultured by direct imprint after disinfection with 70% isopropyl alcohol, 1% triclosan, or 1% chlorhexidine and normal use for 4 hours. As a baseline and an immediate effect control, bacterial load of membranes without disinfection and after 1 minute of disinfection with isopropyl alcohol was determined as well. Three hundred seventy cultures of in-use stethoscopes were taken, 74 from each arm. In the baseline arm the median growth was 10 CFU (interquartile range [IQR], 32-42 CFU); meanwhile, in the isopropyl alcohol immediate-effect arm it was 0 CFU (IQR, 0-0 CFU). In the arms cultured after 4 hours, a median growth of 8 CFU (IQR, 1-28 CFU) in the isopropyl alcohol arm, 4 CFU (IQR, 0-17 CFU) in the triclosan arm, and 0 CFU (IQR, 0-1 CFU) in the chlorhexidine arm were seen. No significant differences were observed between the bacterial load of the chlorhexidine arm (after 4 hours of use) and that of the isopropyl alcohol arm (after 1 minute without use) (Z= 2.41; P > .05). Chlorhexidine can inhibit recontamination of stethoscope membranes and its use could help avoid cross-infection. Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  18. Influence of subinhibitory concentrations of antimicrobials on hydrophobicity, adherence and ultra-structure of Fusobacterium nucleatum

    Directory of Open Access Journals (Sweden)

    Okamoto Ana C.

    2002-01-01

    Full Text Available Fusobacterium nucleatum is considered a bridge organism between earlier and later colonizers in dental biofilms and a putative periodontopathogen. In Dentistry, antimicrobial agents are used for treatment and control of infectious diseases associated with dental plaque. Antiseptics have been used in association with antibiotics to reduce infections after oral surgeries. In this study, the influence of subinhibitory concentrations (SC of chlorhexidine, triclosan, penicillin G and metronidazole, on hydrophobicity, adherence to oral epithelial cells, and ultra-structure of F. nucleatum was examined. All isolates were susceptible to chlorhexidine, triclosan, and metronidazole; however, most of the isolates were susceptible to penicillin G, and all of them were hydrophilic when grown with or without antimicrobials. Adherence was decreased by all antimicrobials. Results suggest that adherence of F. nucleatum was influenced by adhesins because structures such as fimbries or capsule were not observed by transmission electronic microscope.

  19. Antibacterial effect of triantibiotic mixture, chlorhexidine gel, and two natural materials Propolis and Aloe vera against Enterococcus faecalis: An ex vivo study

    Directory of Open Access Journals (Sweden)

    Leila Bazvand

    2014-01-01

    Full Text Available Background: The aim of this ex vivo study was to compare the antimicrobial effect of triantibiotic paste, 0.2% chlorhexidine gel, Propolis and Aloe vera on Enterococcus faecalis in deep dentin. Materials and Methods: Ninety fresh extracted single-rooted teeth were used in a dentin block model. Seventy-five teeth were infected with E. faecalis and divided into four experimental groups (n = 15. Experimental groups were treated with triantibiotic mixture with distilled water, 0.2% chlorhexidine gel, 70% ethanol + Propolis and Aloe vera. Fifteen teeth treated with distilled water as the positive control and 15 samples, free of bacterial contamination, were considered as the negative control. Gates-Glidden drill #4 was used for removal of surface dentin and Gates-Glidden drill #5 was used to collect samples of deep dentin. The samples were prepared and colony-forming units were counted. Data were analyzed by one-way ANOVA and post hoc Tukey tests. Statistical significance was defined at P 0.05. Aloe vera had antibacterial effects on E. faecalis, but in comparison with other medicaments, it was less effective (P < 0.05. Conclusion: This experimental study showed that triantibiotic mixture, 0.2% chlorhexidine gel, Propolis and Aleo vera were relatively effective against E. faecalis. All the intracanal medicements had similar effects on E. faecalis in deep dentin except for Aloe vera.

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

    Science.gov (United States)

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

    2017-01-01

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

  1. Antimicrobial Resistance

    Science.gov (United States)

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

  2. Antimicrobial Resistance

    Science.gov (United States)

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

  3. Antimicrobials Treatment

    Science.gov (United States)

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

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

  4. Novel Clostridium difficile Anti-Toxin (TcdA and TcdB Humanized Monoclonal Antibodies Demonstrate In Vitro Neutralization across a Broad Spectrum of Clinical Strains and In Vivo Potency in a Hamster Spore Challenge Model.

    Directory of Open Access Journals (Sweden)

    Hongyu Qiu

    Full Text Available Clostridium difficile (C. difficile infection (CDI is the main cause of nosocomial antibiotic-associated colitis and increased incidence of community-associated diarrhea in industrialized countries. At present, the primary treatment of CDI is antibiotic administration, which is effective but often associated with recurrence, especially in the elderly. Pathogenic strains produce enterotoxin, toxin A (TcdA, and cytotoxin, toxin B (TcdB, which are necessary for C. difficile induced diarrhea and gut pathological changes. Administration of anti-toxin antibodies provides an alternative approach to treat CDI, and has shown promising results in preclinical and clinical studies. In the current study, several humanized anti-TcdA and anti-TcdB monoclonal antibodies were generated and their protective potency was characterized in a hamster infection model. The humanized anti-TcdA (CANmAbA4 and anti-TcdB (CANmAbB4 and CANmAbB1 antibodies showed broad spectrum in vitro neutralization of toxins from clinical strains and neutralization in a mouse toxin challenge model. Moreover, co-administration of humanized antibodies (CANmAbA4 and CANmAbB4 cocktail provided a high level of protection in a dose dependent manner (85% versus 57% survival at day 22 for 50 mg/kg and 20 mg/kg doses, respectively in a hamster gastrointestinal infection (GI model. This study describes the protective effects conferred by novel neutralizing anti-toxin monoclonal antibodies against C. difficile toxins and their potential as therapeutic agents in treating CDI.

  5. Occurrence of antimicrobial resistance in bacteria from diagnostic samples from dogs.

    Science.gov (United States)

    Pedersen, Karl; Pedersen, Kristina; Jensen, Helene; Finster, Kai; Jensen, Vibeke F; Heuer, Ole E

    2007-10-01

    To study the occurrence of antimicrobial resistance among common bacterial pathogens from dogs and relate resistance patterns to data on consumption of antimicrobials. The antimicrobial susceptibility patterns of 201 Staphylococcus intermedius, 37 Streptococcus canis, 39 Pseudomonas aeruginosa, 25 Pasteurella multocida, 29 Proteus spp. and 449 Escherichia coli isolates from clinical submissions from dogs were determined by a broth-dilution method for determination of minimal inhibitory concentration. Data for consumption of antimicrobials were retrieved from VetStat, a national database for reporting antimicrobial prescriptions. The majority of the antimicrobials prescribed for dogs were broad-spectrum compounds, and extended-spectrum penicillins, cephalosporins and sulphonamides + trimethoprim together accounted for 81% of the total amount used for companion animals. Resistance to cephalosporins and amoxicillin with clavulanic acid was very low for all bacterial species examined, except for P. aeruginosa, and resistance to sulphonamides and trimethoprim was low for most species. Among the S. intermedius isolates, 60.2% were resistant to penicillin, 30.2% to fusidic acid and 27.9% to macrolides. Among E. coli isolates, the highest level of resistance was recorded for ampicillin, sulphonamides, trimethoprim, tetracyclines and streptomycin. Certain differences in resistance patterns between isolates from different sites or organs were noticed for E. coli, S. intermedius and Proteus isolates. This investigation provided data on occurrence of antimicrobial resistance in important pathogenic bacteria from dogs, which may be useful for the small animal practitioner. Resistance was low to the compounds that were most often used, but unfortunately, these compounds were broad-spectrum. Data on resistance and usage may form a background for the establishment of a set of recommendations for prudent use of antimicrobials for companion animals.

  6. A novel antimicrobial peptide against dental-caries-associated bacteria.

    Science.gov (United States)

    Chen, Long; Jia, Lili; Zhang, Qiang; Zhou, Xirui; Liu, Zhuqing; Li, Bingjie; Zhu, Zhentai; Wang, Fenwei; Yu, Changyuan; Zhang, Qian; Chen, Feng; Luo, Shi-Zhong

    2017-10-01

    Dental caries, a highly prevalent oral disease, is primarily caused by pathogenic bacteria infection, and most of them are anaerobic. Herein, we investigated the activity of a designed antimicrobial peptide ZXR-2, and found it showed broad-spectrum activity against a variety of Gram-positive and Gram-negative oral bacteria, particularly the caries-related taxa Streptococcus mutans. Time-course killing assays indicated that ZXR-2 killed most bacterial cells within 5 min at 4 × MIC. The mechanism of ZXR-2 involved disruption of cell membranes, as observed by scanning electron microscopy. Moreover, ZXR-2 inhibited the formation of S. mutans biofilm, but showed limited hemolytic effect. Based on its potent antimicrobial activity, rapid killing, and inhibition of S. mutans biofilm formation, ZXR-2 represents a potential therapeutic for the prevention and treatment of dental caries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Polyhexamethylene guanidine hydrochloride shows bactericidal advantages over chlorhexidine digluconate against ESKAPE bacteria.

    Science.gov (United States)

    Zhou, Zhongxin; Wei, Dafu; Lu, Yanhua

    2015-01-01

    More information regarding the bactericidal properties of polyhexamethylene guanidine hydrochloride (PHMG) against clinically important antibiotic-resistant ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens needs to be provided for its uses in infection control. The bactericidal properties of PHMG and chlorhexidine digluconate (CHG) were compared based on their minimum inhibitory concentrations (MICs), minimum bactericidal concentrations, and time-course-killing curves against clinically important antibiotic-susceptible and antibiotic-resistant ESKAPE pathogens. Results showed that PHMG exhibited significantly higher bactericidal activities against methicillin-resistant Staphylococcus aureus, carbapenem-resistant Klebsiella pneumoniae, and ceftazidime-resistant Enterobacter spp. than CHG. A slight bactericidal advantage over CHG was obtained against vancomycin-resistant Enterococcus faecium, ciprofloxacin- and levofloxacin-resistant Acinetobacter spp., and multidrug-resistant Pseudomonas aeruginosa. In previous reports, PHMG had higher antimicrobial activity against almost all tested Gram-negative bacteria and several Gram-positive bacteria than CHG using MIC test. These studies support the further development of covalently bound PHMG in sterile-surface materials and the incorporation of PHMG in novel disinfectant formulas. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

  8. Experimental and Theoretical Investigation of Multispecies Oral Biofilm Resistance to Chlorhexidine Treatment

    Science.gov (United States)

    Shen, Ya; Zhao, Jia; de La Fuente-Núñez, César; Wang, Zhejun; Hancock, Robert E. W.; Roberts, Clive R.; Ma, Jingzhi; Li, Jun; Haapasalo, Markus; Wang, Qi

    2016-06-01

    We investigate recovery of multispecies oral biofilms following chlorhexidine gluconate (CHX) and CHX with surface modifiers (CHX-Plus) treatment. Specifically, we examine the percentage of viable bacteria in the biofilms following their exposure to CHX and CHX-Plus for 1, 3, and 10 minutes, respectively. Before antimicrobial treatment, the biofilms are allowed to grow for three weeks. We find that (a). CHX-Plus kills bacteria in biofilms more effectively than the regular 2% CHX does, (b). cell continues to be killed for up to one week after exposure to the CHX solutions, (c). the biofilms start to recover after two weeks, the percentage of the viable bacteria recovers in the 1 and 3 minutes treatment groups but not in the 10 minutes treatment group after five weeks, and the biofilms fully return to the pretreatment levels after eight weeks. To understand the mechanism, a mathematical model for multiple bacterial phenotypes is developed, adopting the notion that bacterial persisters exist in the biofilms together with regulatory quorum sensing molecules and growth factor proteins. The model reveals the crucial role played by the persisters, quorum sensing molecules, and growth factors in biofilm recovery, accurately predicting the viable bacterial population after CHX treatment.

  9. Experimental and Theoretical Investigation of Multispecies Oral Biofilm Resistance to Chlorhexidine Treatment

    Science.gov (United States)

    Shen, Ya; Zhao, Jia; de la Fuente-Núñez, César; Wang, Zhejun; Hancock, Robert E. W.; Roberts, Clive R.; Ma, Jingzhi; Li, Jun; Haapasalo, Markus; Wang, Qi

    2016-01-01

    We investigate recovery of multispecies oral biofilms following chlorhexidine gluconate (CHX) and CHX with surface modifiers (CHX-Plus) treatment. Specifically, we examine the percentage of viable bacteria in the biofilms following their exposure to CHX and CHX-Plus for 1, 3, and 10 minutes, respectively. Before antimicrobial treatment, the biofilms are allowed to grow for three weeks. We find that (a). CHX-Plus kills bacteria in biofilms more effectively than the regular 2% CHX does, (b). cell continues to be killed for up to one week after exposure to the CHX solutions, (c). the biofilms start to recover after two weeks, the percentage of the viable bacteria recovers in the 1 and 3 minutes treatment groups but not in the 10 minutes treatment group after five weeks, and the biofilms fully return to the pretreatment levels after eight weeks. To understand the mechanism, a mathematical model for multiple bacterial phenotypes is developed, adopting the notion that bacterial persisters exist in the biofilms together with regulatory quorum sensing molecules and growth factor proteins. The model reveals the crucial role played by the persisters, quorum sensing molecules, and growth factors in biofilm recovery, accurately predicting the viable bacterial population after CHX treatment. PMID:27325010

  10. Economic impact of Tegaderm chlorhexidine gluconate (CHG) dressing in critically ill patients.

    Science.gov (United States)

    Thokala, Praveen; Arrowsmith, Martin; Poku, Edith; Martyn-St James, Marissa; Anderson, Jeff; Foster, Steve; Elliott, Tom; Whitehouse, Tony

    2016-09-01

    To estimate the economic impact of a Tegaderm TM chlorhexidine gluconate (CHG) gel dressing compared with a standard intravenous (i.v.) dressing (defined as non-antimicrobial transparent film dressing), used for insertion site care of short-term central venous and arterial catheters (intravascular catheters) in adult critical care patients using a cost-consequence model populated with data from published sources. A decision analytical cost-consequence model was developed which assigned each patient with an indwelling intravascular catheter and a standard dressing, a baseline risk of associated dermatitis, local infection at the catheter insertion site and catheter-related bloodstream infections (CRBSI), estimated from published secondary sources. The risks of these events for patients with a Tegaderm CHG were estimated by applying the effectiveness parameters from the clinical review to the baseline risks. Costs were accrued through costs of intervention (i.e. Tegaderm CHG or standard intravenous dressing) and hospital treatment costs depended on whether the patients had local dermatitis, local infection or CRBSI. Total costs were estimated as mean values of 10,000 probabilistic sensitivity analysis (PSA) runs. Tegaderm CHG resulted in an average cost-saving of £77 per patient in an intensive care unit. Tegaderm CHG also has a 98.5% probability of being cost-saving compared to standard i.v. dressings. The analyses suggest that Tegaderm CHG is a cost-saving strategy to reduce CRBSI and the results were robust to sensitivity analyses.

  11. The properties of chlorhexidine and undesired effects of its use in endodontics.

    Science.gov (United States)

    Bernardi, Anarela; Teixeira, Cleonice Silveira

    2015-01-01

    The purpose of this article was to review the literature on the properties of chlorhexidine (CHX) and the adverse effects that may occur from its use in endodontics. In addition, adverse effects that may result from its use, such as dark staining of teeth, chemical interaction with sodium hypochlorite and formed flocculate, biologic hazards, and interactions with the filling material were evaluated. Relevant publications on the use CHX in endodontics were thoroughly reviewed from the literature published between the years 2007 and 2014. The authors conducted an electronic search using the English language databases Medline and PubMed. According to the reviewed studies, it was concluded that CHX has proven antimicrobial activity, excellent substantivity, low surface tension, and low cytotoxicity and genotoxicity that depend on the dose and exposed area. There is scientific evidence showing the possibility of tooth staining and formation of brown precipitate when its use is associated with sodium hypochlorite. On the other hand, it is not well established that its use interferes with the quality of endodontic fillings. With respect to the biologic risks, the degradation of CHX may generate para-chloroaniline and free radicals, which are harmful to the vital tissues. There is no established consensus on the potential risk of CHX. The final considerations of this review will encourage researchers to seek scientific evidence demonstrating the safety of the use and applicability of CHX in endodontic therapy.

  12. Root caries prevention via sodium fluoride, chlorhexidine and silver diamine fluoride in vitro.

    Science.gov (United States)

    Göstemeyer, Gerd; Kohls, Anna; Paris, Sebastian; Schwendicke, Falk

    2018-01-31

    Uncertainty exists as to how to best prevent root caries development. The aim of the present study was to compare sodium fluoride (NaF), chlorhexidine (CHX) and silver diamine fluoride (SDF) varnishes (V) and rinses (R) regarding their caries preventive effect in an artificial caries biofilm model. 140 bovine root dentin samples were cut, polished and embedded. Samples were allocated to seven treatment groups (n = 20/group): Four varnishes (applied once prior biofilm challenge): 38% SDF (SDFV), 35% CHX-varnish (CHXV), 22,600 ppm NaF-varnish (NaFV), placebo-varnish (PV); two rinses (applied once daily during biofilm challenge): 500 ppm NaF solution (NaFR), 0.1% CHX solution (CHXR); one untreated group. Caries was induced in a multi-station, continuous-culture Lactobacillus rhamnosus GG (LGG) biofilm model. Bacteria were inoculated 1 × daily, while 2% sucrose was supplied 8 ×/day followed by artificial saliva for 10 min. After 12 days, mineral loss (ΔZ) was measured in the effect area and adjacent to the varnished areas. Bacterial counts were assessed on de-Man-Rogosa-Sharpe agar. ΔZ was significantly lower in the NaFR group compared with all other groups. Varnishes did not significantly prevent mineral loss in adjacent areas. None of the agents had a significant antimicrobial effect on LGG. Regular fluoride rinses showed highest root caries-preventive effect.

  13. Sterilization of Biofilm on a Titanium Surface Using a Combination of Nonthermal Plasma and Chlorhexidine Digluconate

    Directory of Open Access Journals (Sweden)

    Tripti Thapa Gupta

    2017-01-01

    Full Text Available Nosocomial infections caused by opportunistic bacteria pose major healthcare problem worldwide. Out of the many microorganisms responsible for such infections, Pseudomonas aeruginosa is a ubiquitous bacterium that accounts for 10–20% of hospital-acquired infections. These infections have mortality rates ranging from 18 to 60% and the cost of treatment ranges from $20,000 to $80,000 per infection. The formation of biofilms on medical devices and implants is responsible for the majority of those infections. Only limited progress has been made to prevent this issue in a safe and cost-effective manner. To address this, we propose employing jet plasma to break down and inactivate biofilms in vitro. Moreover, to improve the antimicrobial effect on the biofilm, a treatment method using a combination of jet plasma and a biocide known as chlorhexidine (CHX digluconate was investigated. We found that complete sterilization of P. aeruginosa biofilms can be achieved after combinatorial treatment using plasma and CHX. A decrease in biofilm viability was also observed using confocal laser scanning electron microscopy (CLSM. This treatment method sterilized biofilm-contaminated surfaces in a short treatment time, indicating it to be a potential tool for the removal of biofilms present on medical devices and implants.

  14. Antimicrobial effect of essential oil of Citrus reticulata on Fusobacterium nucleatum associated with periodontal disease

    Directory of Open Access Journals (Sweden)

    Cindy Giohanna Pardo

    2017-07-01

    Full Text Available Chlorhexidine as a treatment of periodontal disease has achieved bactericidal effects over periodontopathogens and oral biofilm. Its use generates adverse effects; therefore natural alternatives are presented with a similar antimicrobial effect. Essential oils have proved effective in controlling dental plaque without the adverse effects of chlorhexidine. The aim of this study was to determine the bacteriostatic and bactericidal effect of essential oil of tangerine against Fusobacterium nucleatum. The extraction of the essential oil was performed by expression of tangerine peels (Arrayana and Oneco varieties. Concentrations at 20%, 40%, 60%, 80% and 100% of the essential oil diluted in 0,02% Tween were evaluated. The bacteriostatic and bactericidal effect was determined by antimicrobial susceptibility testing by disk diffusion. As a positive control 0,2% chlorhexidine and water as negative control were used. Inhibition zone (mm was measured and presence or absence of bacterial growth was determined from colony forming units.  To compare proportions of bacteriostatic and bactericidal activity, Fisher and T student test (95% CI p = 0,05 were performed. The 100% concentration zone of inhibition showed a similar behavior as chlorhexidine (p 0,05. The use of essential oils of tangerine could be a complementary alternative to treatment of periodontal disease.

  15. In vitro and in vivo evaluations of glass-ionomer cement containing chlorhexidine for Atraumatic Restorative Treatment

    Science.gov (United States)

    Duque, Cristiane; Aida, Kelly Limi; Pereira, Jesse Augusto; Teixeira, Gláucia Schuindt; Caldo-Teixeira, Angela Scarparo; Perrone, Luciana Rodrigues; Caiaffa, Karina Sampaio; Negrini, Thais de Cássia; de Castilho, Aline Rogéria Freire; Costa, Carlos Alberto de Souza

    2017-01-01

    Abstract Objectives: Addition of chlorhexidine has enhanced the antimicrobial effect of glass ionomer cement (GIC) indicated to Atraumatic Restorative Treatment (ART); however, the impact of this mixture on the properties of these materials and on the longevity of restorations must be investigated. The aim of this study was to evaluate the effects of incorporating chlorhexidine (CHX) in the in vitro biological and chemical-mechanical properties of GIC and in vivo clinical/ microbiological follow-up of the ART with GIC containing or not CHX. Material and Methods: For in vitro studies, groups were divided into GIC, GIC with 1.25% CHX, and GIC with 2.5% CHX. Antimicrobial activity of GIC was analyzed using agar diffusion and anti-biofilm assays. Cytotoxic effects, compressive tensile strength, microhardness and fluoride (F) release were also evaluated. A randomized controlled trial was conducted on 36 children that received ART either with GIC or GIC with CHX. Saliva and biofilm were collected for mutans streptococci (MS) counts and the survival rate of restorations was checked after 7 days, 3 months and one year after ART. ANOVA/Tukey or Kruskal-Wallis/ Mann-Whitney tests were performed for in vitro tests and in vivo microbiological analysis. The Kaplan-Meier method and Log rank tests were applied to estimate survival percentages of restorations (p<0.05). Results: Incorporation of 1.25% and 2.5% CHX improved the antimicrobial/anti-biofilm activity of GIC, without affecting F release and mechanical characteristics, but 2.5% CHX was cytotoxic. Survival rate of restorations using GIC with 1.25% CHX was similar to GIC. A significant reduction of MS levels was observed for KM+CHX group in children saliva and biofilm 7 days after treatment. Conclusions: The incorporation of 1.25% CHX increased the in vitro antimicrobial activity, without changing chemical-mechanical properties of GIC and odontoblast-like cell viability. This combination improved the in vivo short

  16. External immunity in ant societies: sociality and colony size do not predict investment in antimicrobials

    Science.gov (United States)

    Halawani, Omar; Pearson, Bria; Mathews, Stephanie; López-Uribe, Margarita M.; Dunn, Robert R.; Smith, Adrian A.

    2018-01-01

    Social insects live in dense groups with a high probability of disease transmission and have therefore faced strong pressures to develop defences against pathogens. For this reason, social insects have been hypothesized to invest in antimicrobial secretions as a mechanism of external immunity to prevent the spread of disease. However, empirical studies linking the evolution of sociality with increased investment in antimicrobials have been relatively few. Here we quantify the strength of antimicrobial secretions among 20 ant species that cover a broad spectrum of ant diversity and colony sizes. We extracted external compounds from ant workers to test whether they inhibited the growth of the bacterium Staphylococcus epidermidis. Because all ant species are highly social, we predicted that all species would exhibit some antimicrobial activity and that species that form the largest colonies would exhibit the strongest antimicrobial response. Our comparative approach revealed that strong surface antimicrobials are common to particular ant clades, but 40% of species exhibited no antimicrobial activity at all. We also found no correlation between antimicrobial activity and colony size. Rather than relying on antimicrobial secretions as external immunity to control pathogen spread, many ant species have probably developed alternative strategies to defend against disease pressure. PMID:29515850

  17. Prevalence of chlorhexidine-resistant methicillin-resistant Staphylococcus aureus following prolonged exposure.

    Science.gov (United States)

    Schlett, Carey D; Millar, Eugene V; Crawford, Katrina B; Cui, Tianyuan; Lanier, Jeffrey B; Tribble, David R; Ellis, Michael W

    2014-08-01

    Chlorhexidine has been increasingly utilized in outpatient settings to control methicillin-resistant Staphylococcus aureus (MRSA) outbreaks and as a component of programs for MRSA decolonization and prevention of skin and soft-tissue infections (SSTIs). The objective of this study was to determine the prevalence of chlorhexidine resistance in clinical and colonizing MRSA isolates obtained in the context of a community-based cluster-randomized controlled trial for SSTI prevention, during which 10,030 soldiers were issued chlorhexidine for body washing. We obtained epidemiological data on study participants and performed molecular analysis of MRSA isolates, including PCR assays for determinants of chlorhexidine resistance and high-level mupirocin resistance and pulsed-field gel electrophoresis (PFGE). During the study period, May 2010 to January 2012, we identified 720 MRSA isolates, of which 615 (85.4%) were available for molecular analysis, i.e., 341 clinical and 274 colonizing isolates. Overall, only 10 (1.6%) of 615 isolates were chlorhexidine resistant, including three from the chlorhexidine group and seven from nonchlorhexidine groups (P > 0.99). Five (1.5%) of the 341 clinical isolates and five (1.8%) of the 274 colonizing isolates harbored chlorhexidine resistance genes, and four (40%) of the 10 possessed genetic determinants for mupirocin resistance. All chlorhexidine-resistant isolates were USA300. The overall prevalence of chlorhexidine resistance in MRSA isolates obtained from our study participants was low. We found no association between extended chlorhexidine use and the prevalence of chlorhexidine-resistant MRSA isolates; however, continued surveillance is warranted, as this agent continues to be utilized for infection control and prevention efforts. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  18. Prophylactic and metaphylactic antimicrobial use in Belgian fattening pig herds.

    Science.gov (United States)

    Callens, Bénédicte; Persoons, Davy; Maes, Dominiek; Laanen, Maria; Postma, Merel; Boyen, Filip; Haesebrouck, Freddy; Butaye, Patrick; Catry, Boudewijn; Dewulf, Jeroen

    2012-09-01

    The monitoring of antimicrobial use is an essential step to control the selection and spread of antimicrobial resistance. Between January and October 2010 data on prophylactic and metaphylactic antimicrobial use were collected retrospectively on 50 closed or semi-closed pig herds. Ninety-three percent of the group treatments were prophylactic whereas only 7% were methaphylactic. The most frequently used antimicrobials orally applied at group level were colistin (30.7%), amoxicillin (30.0%), trimethoprim-sulfonamides (13.1%), doxycycline (9.9%) and tylosin (8.1%). The most frequently applied injectable antimicrobials were tulathromycin (45.0%), long acting ceftiofur (40.1%) and long acting amoxicillin (8.4%). The treatment incidences (TI) based on the used daily dose pig (UDD(pig) or the actually administered dose per day per kg pig of a drug) for all oral and injectable antimicrobial drugs was on average 200.7 per 1000 pigs at risk per day (min=0, max=699.0), while the TI based on the animal daily dose pig (ADD(pig) or the national defined average maintenance dose per day per kg pig of a drug used for its main indication) was slightly higher (average=235.8, min=0, max=1322.1). This indicates that in reality fewer pigs were treated with the same amount of antimicrobials than theoretically possible. Injectable products were generally overdosed (79.5%), whereas oral treatments were often underdosed (47.3%). In conclusion, this study shows that prophylactic group treatment was applied in 98% of the visited herds and often includes the use of critically important and broad-spectrum antimicrobials. In Belgium, the guidelines for prudent use of antimicrobials are not yet implemented. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. A Randomized Double-Blind, Placebo Controlled, Four-Arm Parallel Study Investigating the Effect of a Broad-Spectrum Wellness Beverage on Mood State in Healthy, Moderately Stressed Adults.

    Science.gov (United States)

    Evans, Malkanthi; Antony, Joseph; Guthrie, Najla; Landes, Bernie; Aruoma, Okezie I

    2018-01-01

    The objective of this study was to investigate the effect of a broad-spectrum wellness beverage (Zeal Wellness [ZW]) on standardized measures of mood states, including overall feelings of vitality, in healthy, moderately stressed adults. A randomized, double-blind, placebo-controlled clinical trial was conducted among 99 eligible participants prescreened for moderate stress. Participants were randomized to one of four groups and received ZW once daily (1-dose-ZW; 14 g), ZW twice daily (2-dose-ZW; 28 g), placebo once daily (1-dose-placebo), or placebo twice daily (2-dose-placebo) for 4 weeks. A stress/vitality questionnaire assessed stress and the Profile of Moods (POMS) Questionnaire assessed vigor via mental/physical energy and global mood state. Safety was assessed by clinical chemistry, liver, kidney function, and anthropometric measures and adverse event reporting. Participants receiving 2-dose-ZW reported a 6.6% decrease in scores on POMS-Total Mood Disturbance (TMD; p < 0.05) and a 6.8% decrease in the anger-hostility mood state (p < 0.022) compared to the combined placebo group at day 29. The 2-dose-ZW provided a 12.8% greater improvement in POMS-TMD scores when compared to participants receiving 1-dose-ZW after 28 days of supplementation (p = 0.014). Within groups, there was a 22.4% and a 9.6% decrease in POMS-TMD scores in participants with 2-dose-ZW and 1-dose-ZW, respectively. In addition, participants receiving 2-dose-ZW showed significant improvements (p = 0.001) in the POMS t-score iceberg profile, which represented a shift to a more healthy profile. These data show that daily supplementation with 2-dose-ZW significantly decreased POMS-TMD scores and anger-hostility mood state and shifted the POMS iceberg profile to a healthy profile compared to the combined placebo, reflecting the functional benefit of rice-bran-fruit-vegetable extracts based beverage on health.

  20. Recently introduced qacA/B genes in Staphylococcus epidermidis do not increase chlorhexidine MIC/MBC

    DEFF Research Database (Denmark)

    Skovgaard, Sissel; Larsen, Marianne Halberg; Nielsen, Lene Nørby

    2013-01-01

    Chlorhexidine is used as a disinfectant to prevent surgical infections. Recently, studies have indicated that chlorhexidine usage has selected methicillin-resistant Staphylococcus aureus strains that are tolerant to chlorhexidine and that this may be related to the presence of the qacA/B-encoded ...

  1. Antimicrobial resistance

    DEFF Research Database (Denmark)

    Llor, Carl; Bjerrum, Lars

    2014-01-01

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

  2. Antimicrobial peptides of buffalo and their role in host defenses

    Directory of Open Access Journals (Sweden)

    Khangembam Victoria Chanu

    2018-02-01

    Full Text Available Antimicrobial peptides (AMPs are highly conserved components of the innate immune system found among all classes of life. Buffalo (Bubalus bubalis, an important livestock for milk and meat production, is known to have a better resistance to many diseases as compared to cattle. They are found to express many AMPs such as defensins, cathelicidins, and hepcidin which play an important role in neutralizing the invading pathogens. Buffalo AMPs exhibit broad-spectrum antimicrobial activity against both Gram-positive and Gram-negative bacteria. Similar to its natural form, synthetic analogs of buffalo AMPs are also antimicrobial against bacteria and even fungus making them a good target for the development of therapeutic antimicrobials. In addition to its antimicrobial effect, AMPs have been demonstrated to have a number of immunomodulatory functions, and their genes are responsive to infections. Further, induction of their gene expression by external factors may help in preventing infectious diseases. This review briefly discusses the AMPs of buffalo identified to date and their possible role in innate immunity.

  3. Antimicrobial peptides of buffalo and their role in host defenses.

    Science.gov (United States)

    Chanu, Khangembam Victoria; Thakuria, Dimpal; Kumar, Satish

    2018-02-01

    Antimicrobial peptides (AMPs) are highly conserved components of the innate immune system found among all classes of life. Buffalo ( Bubalus bubalis ), an important livestock for milk and meat production, is known to have a better resistance to many diseases as compared to cattle. They are found to express many AMPs such as defensins, cathelicidins, and hepcidin which play an important role in neutralizing the invading pathogens. Buffalo AMPs exhibit broad-spectrum antimicrobial activity against both Gram-positive and Gram-negative bacteria. Similar to its natural form, synthetic analogs of buffalo AMPs are also antimicrobial against bacteria and even fungus making them a good target for the development of therapeutic antimicrobials. In addition to its antimicrobial effect, AMPs have been demonstrated to have a number of immunomodulatory functions, and their genes are responsive to infections. Further, induction of their gene expression by external factors may help in preventing infectious diseases. This review briefly discusses the AMPs of buffalo identified to date and their possible role in innate immunity.

  4. Guanidylation and tail effects in cationic antimicrobial lipopeptoids.

    Directory of Open Access Journals (Sweden)

    Brandon Findlay

    Full Text Available Cationic antimicrobial peptides (CAMPs are attractive scaffolds for the next generation of antimicrobial compounds, due to their broad spectrum of activity against multi-drug resistant bacteria and the reduced fitness of CAMP-insensitive mutants. Unfortunately, they are limited by poor in vivo performance, including ready cleavage by endogenous serum proteases.To explore the potential for peptoid residues to replace well studied CAMP scaffolds we have produced a series of antimicrobial lipopeptoids, with sequences similar to previously reported lipopeptides. The activity of the peptoids was assessed against a panel of clinically relevant and laboratory reference bacteria, and the potential for non-specific binding was determined through hemolytic testing and repeating the antimicrobial testing in the presence of added bovine serum albumin (BSA. The most active peptoids displayed good to moderate activity against most of the gram positive strains tested and moderate to limited activity against the gram negatives. Antimicrobial activity was positively correlated with toxicity towards eukaryotic cells, but was almost completely eliminated by adding BSA.The lipopeptoids had similar activities to the previously reported lipopeptides, confirming their potential to act as replacement, proteolytically stable scaffolds for CAMPs.

  5. Chlorhexidine with or without alcohol against biofilm formation: efficacy, adverse events and taste preference.

    Science.gov (United States)

    Santos, Gabriela Otero Dos; Milanesi, Fernanda Carpes; Greggianin, Bruna Frizon; Fernandes, Marilene Issa; Oppermann, Rui Vicente; Weidlich, Patricia

    2017-05-04

    In recent years, different chlorhexidine formulations have been tested, including an alcohol-free alternative, but the effect of this solution on early biofilm formation is not clear. A crossover, randomized, double-blind clinical trial was conducted to evaluate the effect of two chlorhexidine solutions against supra- and subgingival biofilm formation (NCT#02656251). Thirty-five participants were randomized and asked to rinse twice daily with 15 ml of an alcohol-containing 0.12% chlorhexidine solution, an alcohol-free 0.12% chlorhexidine solution, or placebo. The study was conducted in three experimental periods of 4 days each, with a 10-day washout between the periods. All the experimental periods followed the same protocol, except that the solutions were switched. Biofilm distribution was evaluated every 24 hours by the Plaque-Free Zone Index, during 96 hours. Adverse events were self-reported and sensory evaluation was performed using a hedonic scale. Compared to the placebo, the chlorhexidine solutions resulted in a significantly higher number of surfaces free of plaque over 96 hours (p alcohol-free chlorhexidine solution was associated with a lower incidence of adverse events, compared with alcohol-containing chlorhexidine (p alcohol-containing chlorhexidine (p = 0.007), and had a similar inhibitory effect on the formation of supra- and subgingival biofilms.

  6. Differential actions of chlorhexidine on the cell wall of Bacillus subtilis and Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Hon-Yeung Cheung

    Full Text Available Chlorhexidine is a chlorinated phenolic disinfectant used commonly in mouthwash for its action against bacteria. However, a comparative study of the action of chlorhexidine on the cell morphology of gram-positive and gram-negative bacteria is lacking. In this study, the actions of chlorhexidine on the cell morphology were identified with the aids of electron microscopy. After exposure to chlorhexidine, numerous spots of indentation on the cell wall were found in both Bacillus subtilis and Escherichia coli. The number of indentation spots increased with time of incubation and increasing chlorhexidine concentration. Interestingly, the dented spots found in B. subtilis appeared mainly at the hemispherical caps of the cells, while in E. coli the dented spots were found all over the cells. After being exposed to chlorhexidine for a prolonged period, leakage of cellular contents and subsequent ghost cells were observed, especially from B subtilis. By using 2-D gel/MS-MS analysis, five proteins related to purine nucleoside interconversion and metabolism were preferentially induced in the cell wall of E. coli, while three proteins related to stress response and four others in amino acid biosynthesis were up-regulated in the cell wall materials of B. subtilis. The localized morphological damages together with the biochemical and protein analysis of the chlorhexidine-treated cells suggest that chlorhexidine may act on the differentially distributed lipids in the cell membranes/wall of B. subtilis and E. coli.

  7. Formulation and stability of an extemporaneous 0.02% chlorhexidine digluconate ophthalmic solution

    Directory of Open Access Journals (Sweden)

    Shu-Chiao Lin

    2015-12-01

    Conclusion: The acetate-buffered 0.02% chlorhexidine digluconate ophthalmic solution stored in light-resistant high-density polyethylene eyedroppers demonstrated excellent stability at 2–25°C for 6 months after being sealed and for 1 month after opening. This finding will enable us to prepare 0.02% chlorhexidine digluconate ophthalmic solutions based on a doctor's prescription.

  8. Pectin gelation with chlorhexidine: Physico-chemical studies in dilute solutions.

    Science.gov (United States)

    Lascol, Manon; Bourgeois, Sandrine; Guillière, Florence; Hangouët, Marie; Raffin, Guy; Marote, Pedro; Lantéri, Pierre; Bordes, Claire

    2016-10-05

    Low methoxyl pectin is known to gel with divalent cations (e.g. Ca(2+), Zn(2+)). In this study, a new way of pectin gelation in the presence of an active pharmaceutical ingredient, chlorhexidine (CX), was highlighted. Thus chlorhexidine interactions with pectin were investigated and compared with the well-known pectin/Ca(2+) binding model. Gelation mechanisms were studied by several physico-chemical methods such as zeta potential, viscosity, size measurements and binding isotherm was determined by Proton Nuclear Magnetic Resonance Spectroscopy ((1)H NMR). The binding process exhibited similar first two steps for both divalent ions: a stoichiometric monocomplexation of the polymer followed by a dimerization step. However, stronger interactions were observed between pectin and chlorhexidine. Moreover, the dimerization step occurred under stoichiometric conditions with chlorhexidine whereas non-stoichiometric conditions were involved with calcium ions. In the case of chlorhexidine, an additional intermolecular binding occurred in a third step. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Standardized testing with chlorhexidine in perioperative allergy – a large single-centre evaluation

    DEFF Research Database (Denmark)

    Schjørring Opstrup, Morten; Malling, Hans-Jørgen; Krøigaard, Mogens

    2014-01-01

    the diameter of negative control. Chlorhexidine allergy was post hoc defined as a relevant clinical reaction to chlorhexidine combined with two or more positive tests. Based on this definition, sensitivity and specificity were estimated for each test. RESULTS: In total, 22 out of 228 patients (9.6%) met...... the definition of allergy to chlorhexidine. Estimated sensitivity and specificity: specific IgE (sensitivity 100% and specificity 97%), HR (sensitivity 55% and specificity 99%), SPT (sensitivity 95% and specificity 97%) and IDT (sensitivity 68% and specificity 100%). CONCLUSIONS: In patients investigated...... for suspected perioperative allergic reactions, 9.6% were diagnosed with allergy to chlorhexidine. Using our definition of chlorhexidine allergy, the highest combined estimated sensitivity and specificity was found for specific IgE and SPT. This article is protected by copyright. All rights reserved....

  10. Animation of Antimicrobial Resistance

    Medline Plus

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

  11. Antimicrobial residual effects of irrigation regimens with maleic acid in infected root canals

    OpenAIRE

    Ferrer-Luque, Carmen Mar?a; Gonz?lez-Castillo, Silvia; Ruiz-Linares, Matilde; Arias-Moliz, Mar?a Teresa; Rodr?guez-Archilla, Alberto; Baca, Pilar

    2015-01-01

    Background The success of endodontic treatment depends largely on the control of microorganisms present in infected root canals. The aim of this study was to determine the residual antimicrobial activity of several final irrigation protocols with 7% maleic acid (MA) alone and combined with chlorhexidine (CHX), cetrimide (CTR) or both, in root canals infected with Enterococcus faecalis. Biofilms of E. faecalis were grown in uniradicular roots for 4 weeks. A total of 72 specimens were divided i...

  12. Chlorhexidine for prevention of alveolar osteitis: a randomised clinical trial

    Directory of Open Access Journals (Sweden)

    Diego Halabi

    2018-05-01

    Full Text Available Abstract Objective To determine the effectiveness of chlorhexidine 0.12% mouthwash (CHX after tooth extraction for the prevention of alveolar osteitis (AO. Material and methods We conducted a double-blind randomised clinical trial stratified by risk factors. We enrolled a cohort of 822 patients who underwent dental extractions, and were considered to be at risk of developing AO (previous surgical site infection, traumatic extraction, and tobacco smoking. After extraction, patients were randomly allocated for CHX group or placebo group, matched by risk factors. The primary outcome was clinical diagnosis of AO: increasing postoperative pain for 4 d within and around the socket, and total or partial breakdown of the blood clot in the socket with or without bone exposure. Results Follow-up was completed by 744 participants (372 chlorhexidine and 372 placebo. We detected no significant differences between the two groups at baseline. After completed follow-up, risk factors were equally distributed between the two groups. Overall incidence of OA was 4.97%, in which 27 participants treated with placebo (7.26% and 10 participants treated with CHX (2.69% developed AO. CHX reduced the incidence of AO by 63% [Absolute Risk Reduction: 4.57 (95% CI 1.5-7.7, Number Needed to Treat: 21.88 (95% CI 13.0-69.3, Fisher's exact test: p=0.006]. No adverse effects were reported. Conclusion The use of chlorhexidine 0.12% mouthwash after tooth extraction is safe and effective in reducing the incidence of AO in high-risk patients.

  13. Repurposing Auranofin, Ebselen, and PX-12 as Antimicrobial Agents Targeting the Thioredoxin System

    Directory of Open Access Journals (Sweden)

    Holly C. May

    2018-03-01

    Full Text Available As microbial resistance to drugs continues to rise at an alarming rate, finding new ways to combat pathogens is an issue of utmost importance. Development of novel and specific antimicrobial drugs is a time-consuming and expensive process. However, the re-purposing of previously tested and/or approved drugs could be a feasible way to circumvent this long and costly process. In this review, we evaluate the U.S. Food and Drug Administration tested drugs auranofin, ebselen, and PX-12 as antimicrobial agents targeting the thioredoxin system. These drugs have been shown to act on bacterial, fungal, protozoan, and helminth pathogens without significant toxicity to the host. We propose that the thioredoxin system could serve as a useful therapeutic target with broad spectrum antimicrobial activity.

  14. [Overdentures covering natural roots. The use of chlorhexidine gel].

    Science.gov (United States)

    Hendrikx, M J; Kramer, J E; de Baat, C

    2000-03-01

    To prevent caries and periodontal disease in overdenture abutment teeth, daily application of chlorhexidine gel is recommended. In order to get insight into the use of the gel, 29 overdenture wearing patients were interviewed. In addition the patients were requested to show the use of the gel. It was concluded that at any time the patients were instructed about the use of the gel. Nevertheless, a majority of the patients did not use the gel daily and in accordance with the instructions given. Application of the gel in the abutment depressions of the overdenture appeared to be a heavy task.

  15. Antimicrobial Efficacy of Salvadora persica Extracts on a Monospecies Biofilm on Orthodontic Brackets In Vitro.

    Science.gov (United States)

    Halawany, Hassan S; Abraham, Nimmi B; Siddiqui, Yunus M; Balto, Hanan A; Jacob, Vimal

    2016-01-01

    The oral cavity is a rich ecosystem with a plethora of microorganisms, and different components of fixed orthodontic appliances may contribute to a shift in the balance of oral ecology. The purpose of this study was to investigate the antimicrobial potential of hexane and ethanol extracts of Salvadora persica on a monospecies biofilm model established on orthodontic brackets in vitro. Streptococcus mutans biofilm was formed on mini diamond orthodontic brackets following three days of anaerobic incubation at 37˚C. The bacterial cell viability of this biofilm was measured after their exposure to saline, hexane extract of S. persica, ethanol extract of S. persica and 0.2% chlorhexidine using 3-(4, 5-dimethylthiazol- 2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) assay. On half of the brackets, the colony forming units (CFU) were counted. Both experiments were performed in triplicate. The absorbance values obtained from the MTS reduction assay after exposure to the different test agents showed a decline in the bacterial cell viability of the S. mutans biofilm as follows: chlorhexidine (+)0.05). The CFU counts of S. mutans obtained from chlorhexidine exposure were lower than from hexane and ethanol extracts. S. persica extracts were found to have antimicrobial effects on S. mutans biofilm established in vitro on orthodontic brackets suggestive of its potential use as an oral antimicrobial agent for orthodontic patients.

  16. Susceptibility of some oral microorganisms to chlorhexidine and paramonochlorophenol Susceptibilidade de alguns microrganismos orais frente à clorexidina e ao paramonoclorofenol

    Directory of Open Access Journals (Sweden)

    Crystiane Venditi Gomes do Amorim

    2004-09-01

    Full Text Available Since the use of antimicrobial agents is required in endodontic therapies, this study aimed at determining the minimum inhibitory concentrations (MICs of chlorhexidine digluconate and paramonochlorophenol (PMC against microorganisms commonly found in endodontic infections. Both agents were tested by agar dilution tests against Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Candida albicans, Prevotella intermedia, Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella denticola and Prevotella melaninogenica. The MIC of chlorhexidine ranged from 2.67 to 80.00 µg/ml, and the MIC of PMC from 46.67 to 213.33 µg/ml. The highest MIC value of PMC was detected for E. faecalis whereas E. coli was the most susceptible microorganism to this agent. The highest MIC values of chlorhexidine were observed for P. aeruginosa whereas E. coli and P. denticola were the most susceptible microorganisms to this agent. Since the MIC values observed are much lower than the concentrations currently used in the endodontic therapy, it is suggested that both agents are effective in reducing the microbiota in the root canal.Tendo em vista a necessidade de se utilizarem agentes antimicrobianos durante a terapia endodôntica, o presente estudo tem por objetivo determinar as concentrações inibitórias mínimas (CIMs de digluconato de clorexidina e de paramonoclorofenol (PMC frente a cepas de microrganismos freqüentemente isolados dos canais radiculares infectados. Ambos os agentes foram testados por meio de testes de diluição em meio sólido contra Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Candida albicans, Prevotella intermedia, Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella denticola e Prevotella melaninogenica. As CIMs de clorexidina variaram de 2,67 a 80,00 µg/ml, e as CIMs de PMC variaram de 46,67 a 213,33 µg/ml. A maior CIM do paramonoclorofenol foi

  17. Distinct Profiling of Antimicrobial Peptide Families

    KAUST Repository

    Khamis, Abdullah M.

    2014-11-10

    Motivation: The increased prevalence of multi-drug resistant (MDR) pathogens heightens the need to design new antimicrobial agents. Antimicrobial peptides (AMPs) exhibit broad-spectrum potent activity against MDR pathogens and kills rapidly, thus giving rise to AMPs being recognized as a potential substitute for conventional antibiotics. Designing new AMPs using current in-silico approaches is, however, challenging due to the absence of suitable models, large number of design parameters, testing cycles, production time and cost. To date, AMPs have merely been categorized into families according to their primary sequences, structures and functions. The ability to computationally determine the properties that discriminate AMP families from each other could help in exploring the key characteristics of these families and facilitate the in-silico design of synthetic AMPs. Results: Here we studied 14 AMP families and sub-families. We selected a specific description of AMP amino acid sequence and identified compositional and physicochemical properties of amino acids that accurately distinguish each AMP family from all other AMPs with an average sensitivity, specificity and precision of 92.88%, 99.86% and 95.96%, respectively. Many of our identified discriminative properties have been shown to be compositional or functional characteristics of the corresponding AMP family in literature. We suggest that these properties could serve as guides for in-silico methods in design of novel synthetic AMPs. The methodology we developed is generic and has a potential to be applied for characterization of any protein family.

  18. An environmentally benign antimicrobial nanoparticle based ...

    Science.gov (United States)

    Silver nanoparticles have antibacterial properties but their use has been a cause for concern because they persist in the environment. Here we show that lignin nanoparticles infused with silver ions and coated with a cationic polyelectrolyte layer form a biodegradable and green alternative to silver nanoparticles. The polyelectrolyte layer promotes the adhesion of the particles to bacterial cell membranes and together with silver ions can kill a broad spectrum of bacteria, including Escherichia coli, Pseudomonas aeruginosa and quaternary-amine-resistant Ralstonia sp. Ion depletion studies showed that the bioactivity of these nanoparticles is time-limited because of the desorption of silver ions. High-throughput bioactivity screening did not reveal increased toxicity of the particles when compared to an equivalent mass of metallic silver nanoparticles or silver nitrate solution. Our results demonstrate that the application of green chemistry principles may allow the synthesis of nanoparticles with biodegradable cores that have higher antimicrobial activity and smaller environmental impact than metallic silver nanoparticles. Our results demonstrate that the application of green chemistry principles may allow the synthesis of nanoparticles with biodegradable cores that have higher antimicrobial activity and smaller environmental impact than metallic silver nanoparticles

  19. Distinct Profiling of Antimicrobial Peptide Families

    KAUST Repository

    Khamis, Abdullah M.; Essack, Magbubah; Gao, Xin; Bajic, Vladimir B.

    2014-01-01

    Motivation: The increased prevalence of multi-drug resistant (MDR) pathogens heightens the need to design new antimicrobial agents. Antimicrobial peptides (AMPs) exhibit broad-spectrum potent activity against MDR pathogens and kills rapidly, thus giving rise to AMPs being recognized as a potential substitute for conventional antibiotics. Designing new AMPs using current in-silico approaches is, however, challenging due to the absence of suitable models, large number of design parameters, testing cycles, production time and cost. To date, AMPs have merely been categorized into families according to their primary sequences, structures and functions. The ability to computationally determine the properties that discriminate AMP families from each other could help in exploring the key characteristics of these families and facilitate the in-silico design of synthetic AMPs. Results: Here we studied 14 AMP families and sub-families. We selected a specific description of AMP amino acid sequence and identified compositional and physicochemical properties of amino acids that accurately distinguish each AMP family from all other AMPs with an average sensitivity, specificity and precision of 92.88%, 99.86% and 95.96%, respectively. Many of our identified discriminative properties have been shown to be compositional or functional characteristics of the corresponding AMP family in literature. We suggest that these properties could serve as guides for in-silico methods in design of novel synthetic AMPs. The methodology we developed is generic and has a potential to be applied for characterization of any protein family.

  20. High Rate of qacA- and qacB-Positive Methicillin-Resistant Staphylococcus aureus Isolates from Chlorhexidine-Impregnated Catheter-Related Bloodstream Infections

    OpenAIRE

    Ho, Cheng-Mao; Li, Chi-Yuan; Ho, Mao-Wang; Lin, Chien-Yu; Liu, Shu-Hui; Lu, Jang-Jih

    2012-01-01

    Chlorhexidine has been widely used for infection control. Although the use of chlorhexidine-impregnated catheters has reduced catheter-related infections, chlorhexidine-resistant Staphylococcus aureus has emerged. The correlation between the existence of the chlorhexidine-resistant genes qacA and qacB (qacA/B) in methicillin-resistant Staphylococcus aureus (MRSA) isolates and the effectiveness of chlorhexidine-impregnated catheters in the prevention of MRSA infections is unknown. Sixty methic...

  1. Mechanisms of antimicrobial resistance among hospital-associated pathogens.

    Science.gov (United States)

    Khan, Ayesha; Miller, William R; Arias, Cesar A

    2018-04-01

    The introduction of antibiotics revolutionized medicine in the 20th-century permitting the treatment of once incurable infections. Widespread use of antibiotics, however, has led to the development of resistant organisms, particularly in the healthcare setting. Today, the clinician is often faced with pathogens carrying a cadre of resistance determinants that severely limit therapeutic options. The genetic plasticity of microbes allows them to adapt to stressors via genetic mutations, acquisition or sharing of genetic material and modulation of genetic expression leading to resistance to virtually any antimicrobial used in clinical practice. Areas covered: This is a comprehensive review that outlines major mechanisms of resistance in the most common hospital-associated pathogens including bacteria and fungi. Expert commentary: Understanding the genetic and biochemical mechanisms of such antimicrobial adaptation is crucial to tackling the rapid spread of resistance, can expose unconventional therapeutic targets to combat multidrug resistant pathogens and lead to more accurate prediction of antimicrobial susceptibility using rapid molecular diagnostics. Clinicians making treatment decisions based on the molecular basis of resistance may design therapeutic strategies that include de-escalation of broad spectrum antimicrobial usage, more focused therapies or combination therapies. These strategies are likely to improve patient outcomes and decrease the risk of resistance in hospital settings.

  2. Advances in Development of Antimicrobial Peptidomimetics as Potential Drugs.

    Science.gov (United States)

    Molchanova, Natalia; Hansen, Paul R; Franzyk, Henrik

    2017-08-29

    The rapid emergence of multidrug-resistant pathogens has evolved into a global health problem as current treatment options are failing for infections caused by pan-resistant bacteria. Hence, novel antibiotics are in high demand, and for this reason antimicrobial peptides (AMPs) have attracted considerable interest, since they often show broad-spectrum activity, fast killing and high cell selectivity. However, the therapeutic potential of natural AMPs is limited by their short plasma half-life. Antimicrobial peptidomimetics mimic the structure and biological activity of AMPs, but display extended stability in the presence of biological matrices. In the present review, focus is on the developments reported in the last decade with respect to their design, synthesis, antimicrobial activity, cytotoxic side effects as well as their potential applications as anti-infective agents. Specifically, only peptidomimetics with a modular structure of residues connected via amide linkages will be discussed. These comprise the classes of α-peptoids ( N -alkylated glycine oligomers), β-peptoids ( N -alkylated β-alanine oligomers), β³-peptides, α/β³-peptides, α-peptide/β-peptoid hybrids, α/γ N -acylated N -aminoethylpeptides (AApeptides), and oligoacyllysines (OAKs). Such peptidomimetics are of particular interest due to their potent antimicrobial activity, versatile design, and convenient optimization via assembly by standard solid-phase procedures.

  3. Characterization of Antimicrobial Peptides toward the Development of Novel Antibiotics

    Directory of Open Access Journals (Sweden)

    Wataru Aoki

    2013-08-01

    Full Text Available Antimicrobial agents have eradicated many infectious diseases and significantly improved our living environment. However, abuse of antimicrobial agents has accelerated the emergence of multidrug-resistant microorganisms, and there is an urgent need for novel antibiotics. Antimicrobial peptides (AMPs have attracted attention as a novel class of antimicrobial agents because AMPs efficiently kill a wide range of species, including bacteria, fungi, and viruses, via a novel mechanism of action. In addition, they are effective against pathogens that are resistant to almost all conventional antibiotics. AMPs have promising properties; they directly disrupt the functions of cellular membranes and nucleic acids, and the rate of appearance of AMP-resistant strains is very low. However, as pharmaceuticals, AMPs exhibit unfavorable properties, such as instability, hemolytic activity, high cost of production, salt sensitivity, and a broad spectrum of activity. Therefore, it is vital to improve these properties to develop novel AMP treatments. Here, we have reviewed the basic biochemical properties of AMPs and the recent strategies used to modulate these properties of AMPs to enhance their safety.

  4. Animation of Antimicrobial Resistance

    Medline Plus

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

  5. Antimicrobial Pesticides

    Science.gov (United States)

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

  6. Synergistic Antibacterial Effects of Nanoparticles Encapsulated with Scutellaria baicalensis and Pure Chlorhexidine on Oral Bacterial Biofilms

    Directory of Open Access Journals (Sweden)

    Ken Cham-Fai Leung

    2016-04-01

    Full Text Available Scutellaria baicalensis (SB is a traditional Chinese medicine for treating infectious and inflammatory diseases. Our recent study shows potent antibacterial effects of nanoparticle-encapsulated chlorhexidine (Nano-CHX. Herein, we explored the synergistic effects of the nanoparticle-encapsulated SB (Nano-SB and Nano-CHX on oral bacterial biofilms. Loading efficiency of Nano-SB was determined by thermogravimetric analysis, and its releasing profile was assessed by high-performance liquid chromatographyusing baicalin (a flavonoid compound of SB as the marker. The mucosal diffusion assay on Nano-SB was undertaken in a porcine model. The antibacterial effects of the mixed nanoparticles (Nano-MIX of Nano-SB and Nano-CHX at 9:1 (w/w ratio were analyzed in both planktonic and biofilm modes of representative oral bacteria. The Nano-MIX was effective on the mono-species biofilms of Streptococcus (S. mutans, S. sobrinus, Fusobacterium (F. nucleatum, and Aggregatibacter (A. actinomycetemcomitans (MIC 50 μg/mL at 24 h, and exhibited an enhanced effect against the multi-species biofilms such as S. mutans, F. nucleatum, A. actinomycetemcomitans, and Porphyromonas (P. gingivalis (MIC 12.5 μg/mL at 24 h that was supported by the findings of both scanning electron microscopy (SEM and confocal scanning laser microscopy (CLSM. This study shows enhanced synergistic antibacterial effects of the Nano-MIX on common oral bacterial biofilms, which could be potentially developed as a novel antimicrobial agent for clinical oral/periodontal care.

  7. Acquired resistance to chlorhexidine - is it time to establish an 'antiseptic stewardship' initiative?

    Science.gov (United States)

    Kampf, G

    2016-11-01

    Chlorhexidine digluconate (CHG) is an antimicrobial agent used for different types of applications in hand hygiene, skin antisepsis, oral care, and patient washing. Increasing use raises concern regarding development of acquired bacterial resistance. Published data from clinical isolates with CHG minimum inhibitory concentrations (MICs) were reviewed and compared to epidemiological cut-off values to determine resistance. CHG resistance is rarely found in Escherichia coli, Salmonella spp., Staphylococcus aureus or coagulase-negative staphylococci. In Enterobacter spp., Pseudomonas spp., Proteus spp., Providencia spp. and Enterococcus spp., however, isolates are more often CHG resistant. CHG resistance may be detected in multi-resistant isolates such as extremely drug-resistant Klebsiella pneumoniae. Isolates with a higher MIC are often less susceptible to CHG for disinfection. Although cross-resistance to antibiotics remains controversial, some studies indicate that the overall exposure to CHG increases the risk for resistance to some antibiotic agents. Resistance to CHG has resulted in numerous outbreaks and healthcare-associated infections. On an average intensive care unit, most of the CHG exposure would be explained by hand hygiene agents when liquid soaps or alcohol-based hand rubs contain CHG. Exposure to sub-lethal CHG concentration may enhance resistance in Acinetobacter spp., K. pneumoniae, and Pseudomonas spp., all species well known for emerging antibiotic resistance. In order to reduce additional selection pressure in nosocomial pathogens it seems to make sense to restrict the valuable agent CHG to those indications with a clear patient benefit and to eliminate it from applications without any benefit or with a doubtful benefit. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  8. Caries lesion remineralization with fluoride toothpastes and chlorhexidine - effects of application timing and toothpaste surfactant

    Directory of Open Access Journals (Sweden)

    Sami A. Almohefer

    2018-06-01

    Full Text Available Abstract Habitual toothbrushing with fluoridated toothpaste followed by rinsing with antibacterial mouthwashes is a method to maintain good oral hygiene and to diminish the occurrence and severity of dental caries and periodontal disease. However, our understanding of how antimicrobial agents in mouthwashes affect fluoride-mediated caries lesion remineralization is still poor. Objective: The objectives of this in vitro study were a to determine the effects of the waiting period of chlorhexidine (CHX rinsing after fluoride toothpaste use and b to further determine the effect of the type of toothpaste surfactant [sodium dodecyl sulfate (SDS or cocamidopropyl betaine (CAPB] on caries lesion remineralization associated with CHX rinsing. Material and Methods: Caries lesions were formed in bovine enamel specimens and assigned to 10 treatment groups (n=18 based on Vickers surface microhardness (VHN. Lesions were then pH-cycled for 10 days with daily regimen comprised of twice daily toothpaste slurry treatments (1150 ppm fluoride, with SDS or CAPB, followed by CHX solution treatments [0, 15, 30 or 60 minutes following slurry treatment or no CHX treatment (negative control]. VHN was measured again and the extent of lesion remineralization calculated (∆VHN. Results: ∆VHN with SDS-toothpaste was significantly lower than with CAPB-toothpaste, indicating more remineralization for the CAPB-toothpaste. ∆VHN with 0-minute waiting time was significantly lower than with 30-minute waiting time and with negative control. Conclusions: The absence of CHX as an adjunct to fluoride toothpastes led to greater remineralization of enamel lesions compared with the immediate use of CHX treatment for both SDS- and CAPB-toothpastes. CAPB-toothpastes indicated significantly greater remineralization than SDS-toothpastes, and can be suggested for patients at high risk of caries. A 30-minute waiting time for CHX treatment is recommended after brushing.

  9. Microscopic and Spectroscopic Analyses of Chlorhexidine Tolerance in Delftia acidovorans Biofilms

    Science.gov (United States)

    Rema, Tara; Lawrence, John R.; Dynes, James J.; Hitchcock, Adam P.

    2014-01-01

    The physicochemical responses of Delftia acidovorans biofilms exposed to the commonly used antimicrobial chlorhexidine (CHX) were examined in this study. A CHX-sensitive mutant (MIC, 1.0 μg ml−1) was derived from a CHX-tolerant (MIC, 15.0 μg ml−1) D. acidovorans parent strain using transposon mutagenesis. D. acidovorans mutant (MT51) and wild-type (WT15) strain biofilms were cultivated in flow cells and then treated with CHX at sub-MIC and inhibitory concentrations and examined by confocal laser scanning microscopy (CLSM), scanning transmission X-ray microscopy (STXM), and infrared (IR) spectroscopy. Specific morphological, structural, and chemical compositional differences between the CHX-treated and -untreated biofilms of both strains were observed. Apart from architectural differences, CLSM revealed a negative effect of CHX on biofilm thickness in the CHX-sensitive MT51 biofilms relative to those of the WT15 strain. STXM analyses showed that the WT15 biofilms contained two morphochemical cell variants, whereas only one type was detected in the MT51 biofilms. The cells in the MT51 biofilms bioaccumulated CHX to a similar extent as one of the cell types found in the WT15 biofilms, whereas the other cell type in the WT15 biofilms did not bioaccumulate CHX. STXM and IR spectral analyses revealed that CHX-sensitive MT51 cells accumulated the highest levels of CHX. Pretreating biofilms with EDTA promoted the accumulation of CHX in all cells. Thus, it is suggested that a subpopulation of cells that do not accumulate CHX appear to be responsible for greater CHX resistance in D. acidovorans WT15 biofilm in conjunction with the possible involvement of bacterial membrane stability. PMID:25022584

  10. Design of the Prevention of Adult Caries Study (PACS: A randomized clinical trial assessing the effect of a chlorhexidine dental coating for the prevention of adult caries

    Directory of Open Access Journals (Sweden)

    Snyder John J

    2010-10-01

    Full Text Available Abstract Background Dental caries is one of the primary causes of tooth loss among adults. It is estimated to affect a majority of Americans aged 55 and older, with a disproportionately higher burden in disadvantaged populations. Although a number of treatments are currently in use for caries prevention in adults, evidence for their efficacy and effectiveness is limited. Methods/Design The Prevention of Adult Caries Study (PACS is a multicenter, placebo-controlled, double-blind, randomized clinical trial of the efficacy of a chlorhexidine (10% w/v dental coating in preventing adult caries. Participants (n = 983 were recruited from four different dental delivery systems serving four diverse communities, including one American Indian population, and were randomized to receive either chlorhexidine or a placebo treatment. The primary outcome is the net caries increment (including non-cavitated lesions from baseline to 13 months of follow-up. A cost-effectiveness analysis also will be considered. Discussion This new dental treatment, if efficacious and approved for use by the Food and Drug Administration (FDA, would become a new in-office, anti-microbial agent for the prevention of adult caries in the United States. Trial Registration Number NCT00357877

  11. Antibacterial effect of triantibiotic mixture, chlorhexidine gel, and two natural materials Propolis and Aloe vera against Enterococcus faecalis: An ex vivo study.

    Science.gov (United States)

    Bazvand, Leila; Aminozarbian, Mohammad Ghasem; Farhad, Alireza; Noormohammadi, Hamid; Hasheminia, Seyed Mohsen; Mobasherizadeh, Sina

    2014-07-01

    The aim of this ex vivo study was to compare the antimicrobial effect of triantibiotic paste, 0.2% chlorhexidine gel, Propolis and Aloe vera on Enterococcus faecalis in deep dentin. Ninety fresh extracted single-rooted teeth were used in a dentin block model. Seventy-five teeth were infected with E. faecalis and divided into four experimental groups (n = 15). Experimental groups were treated with triantibiotic mixture with distilled water, 0.2% chlorhexidine gel, 70% ethanol + Propolis and Aloe vera. Fifteen teeth treated with distilled water as the positive control and 15 samples, free of bacterial contamination, were considered as the negative control. Gates-Glidden drill #4 was used for removal of surface dentin and Gates-Glidden drill #5 was used to collect samples of deep dentin. The samples were prepared and colony-forming units were counted. Data were analyzed by one-way ANOVA and post hoc Tukey tests. Statistical significance was defined at P 0.05). Aloe vera had antibacterial effects on E. faecalis, but in comparison with other medicaments, it was less effective (P vera were relatively effective against E. faecalis. All the intracanal medicements had similar effects on E. faecalis in deep dentin except for Aloe vera.

  12. Genome-wide identification of antimicrobial intrinsic resistance determinants in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Martin Vestergaard

    2016-12-01

    Full Text Available The emergence of antimicrobial resistance severely threatens our ability to treat bacterial infections. While acquired resistance has received considerable attention, relatively little is known of intrinsic resistance that allows bacteria to naturally withstand antimicrobials. Gene products that confer intrinsic resistance to antimicrobial agents may be explored for alternative antimicrobial therapies, by potentiating the efficacy of existing antimicrobials. In this study, we identified the intrinsic resistome to a broad spectrum of antimicrobials in the human pathogen, Staphylococcus aureus. We screened the Nebraska Transposon Mutant Library of 1920 single-gene inactivations in S. aureus strain JE2, for increased susceptibility to the anti-staphylococcal antimicrobials (ciprofloxacin, oxacillin, linezolid, fosfomycin, daptomycin, mupirocin, vancomycin and gentamicin. 68 mutants were confirmed by E-test to display at least two-fold increased susceptibility to one or more antimicrobial agents. The majority of the identified genes have not previously been associated with antimicrobial susceptibility in S. aureus. For example, inactivation of genes encoding for subunits of the ATP synthase, atpA, atpB, atpG and atpH, reduced the minimum inhibitory concentration (MIC of gentamicin 16-fold. To elucidate the potential of the screen, we examined treatment efficacy in the Galleria mellonella infection model. Gentamicin efficacy was significantly improved, when treating larvae infected with the atpA mutant compared to wild type cells with gentamicin at a clinically relevant concentration. Our results demonstrate that many gene products contribute to the intrinsic antimicrobial resistance of S. aureus. Knowledge of these intrinsic resistance determinants provides alternative targets for compounds that may potentiate the efficacy of existing antimicrobial agents against this important pathogen.

  13. Antibacterial effects of electrospun chitosan/poly(ethylene oxide) nanofibrous membranes loaded with chlorhexidine and silver

    NARCIS (Netherlands)

    Song, J.; Remmers, S.J.; Shao, J.; Kolwijck, E.; Walboomers, X.F.; Jansen, J.A.; Leeuwenburgh, S.C.; Yang, F.

    2016-01-01

    To prevent percutaneous device associated infections (PDAIs), we prepared electrospun chitosan/poly(ethylene oxide) (PEO) nanofibrous membrane containing silver nanoparticles as an implantable delivery vehicle for the dual release of chlorhexidine and silver ions. We observed that the silver

  14. Daily chlorhexidine bathing does not increase skin toxicity after remission induction or stem cell transplantation.

    Science.gov (United States)

    Deeren, Dries; Dewulf, Evelyne; Verfaillie, Lydie

    2016-12-01

    A recent multicenter study demonstrated that bathing with chlorhexidine reduces the transmission of resistant organisms and the risk of hospital-acquired bloodstream infections in ICUs. We wanted to confirm the feasibility of this strategy in a cohort of patients in a typical intensive haematology unit. Patients treated with remission induction chemotherapy, autologous or allogeneic stem cell transplantation received daily chlorhexidine bathing. To avoid deshydratation of skin, we used prophylactic application of hydrating lotion, replaced by corticosteroid cream in case of skin toxicity of chemotherapy or conditioning. We studied 15 consecutive admissions of 12 patients. Daily chlorhexidine bathing never needed to be interrupted, even though 53% of patients were treated with intravenous cytarabine. Patients were satisfied with the skin treatment and reported few unwanted effects. Daily chlorhexidine bathing was feasible in our intensive haematology unit in all patients and did not increase skin toxicity, even when treated with IV cytarabine.

  15. Can chlorhexidine mouthwash twice daily ameliorate cyclosporine-induced gingival overgrowth?

    Directory of Open Access Journals (Sweden)

    Ching-Hwa Gau

    2013-03-01

    Conclusion: These findings suggest that chlorhexidine mouthwash used twice daily may reduce the severity of CsA-induced gingival overgrowth. Further research is warranted to determine the optimal dose and treatment regimen.

  16. The caries-preventive effect of chlorhexidine varnish in children and adolescents: a systematic review.

    LENUS (Irish Health Repository)

    James, Patrice

    2010-01-01

    Our purpose was to systematically review the literature on the effectiveness of chlorhexidine varnish for preventing dental caries in children and adolescents and to determine its effectiveness compared to fluoride varnish.

  17. Effect of Achyranthes aspera, 0.2% Aqueous Chlorhexidine Gluconate and Punica granatum Oral Rinse on the Levels of Salivary Streptococcus mutans in 8 to 12 Years Old Children.

    Science.gov (United States)

    Bansal, Aayushi; Marwah, Nikhil; Nigam, Anant Gopal; Goenka, Puneet; Goel, Deepak

    2015-11-01

    To study the effect Achyranthes aspera, 0.2% aqueous chlorhexidine gluconate and Punica granatum oral rinse on salivary Streptococcus mutans count in children. A total of 60 children of 8 to 12 years of age were randomly allocated into 3 groups. Group A was given 0.2% chlorhexidine mouthwash, group B was given 10% A. aspera mouthwash and group C was given 15% P. granatum mouthwash. The day 1 saliva samples were collected from the subjects and inoculated onto mitis salivarius bacitracin (MSB) agar. The colony counts were obtained by a clinical microbiologist who was blinded to the subject allocation. Plaque scores were then recorded by the investigator with the help of a volunteer. Following this, they received a thorough scaling and polishing. Subjects in each group were then provided with 140 ml of the respective mouthwash, as a daily supervised rinse after breakfast and before sleeping as per instructions. Following mouth rinsing, the children were instructed not to eat or drink for 15 minutes. At the 7th day, unstimulated saliva was again collected from the subjects of all 3 groups, inoculated onto MSB agar and colony count was obtained. Modified Quigley-Hein plaque index was also evaluated for the refreshed score at this stage. Colony counting was done using loop method and statistical analysis was done using Statistical Package for the Social Science (SPSS) software version 21. All the three mouthwashes showed statistically significant reduction of S. mutans count and plaque index after 7 days, i.e. chlorhexidine (p granatum (p granatum was statistically significant with respect to reduction of S. mutans count with chlorhexidine being marginally better than the other two; All the three mouthwashes were found to be at par when plaque index values from baseline and after interception of 7 days was calculated; Punica granatum has better antimicrobial effect than A. aspera.

  18. Antimicrobial and biophysical properties of surfactant supplemented with an antimicrobial peptide for treatment of bacterial pneumonia.

    Science.gov (United States)

    Banaschewski, Brandon J H; Veldhuizen, Edwin J A; Keating, Eleonora; Haagsman, Henk P; Zuo, Yi Y; Yamashita, Cory M; Veldhuizen, Ruud A W

    2015-01-01

    Antibiotic-resistant bacterial infections represent an emerging health concern in clinical settings, and a lack of novel developments in the pharmaceutical pipeline is creating a "perfect storm" for multidrug-resistant bacterial infections. Antimicrobial peptides (AMPs) have been suggested as future therapeutics for these drug-resistant bacteria, since they have potent broad-spectrum activity, with little development of resistance. Due to the unique structure of the lung, bacterial pneumonia has the additional problem of delivering antimicrobials to the site of infection. One potential solution is coadministration of AMPs with exogenous surfactant, allowing for distribution of the peptides to distal airways and opening of collapsed lung regions. The objective of this study was to test various surfactant-AMP mixtures with regard to maintaining pulmonary surfactant biophysical properties and bactericidal functions. We compared the properties of four AMPs (CATH-1, CATH-2, CRAMP, and LL-37) suspended in bovine lipid-extract surfactant (BLES) by assessing surfactant-AMP mixture biophysical and antimicrobial functions. Antimicrobial activity was tested against methillicin-resistant Staphylococcus aureus and Pseudomonas aeruginosa. All AMP/surfactant mixtures exhibited an increase of spreading compared to a BLES control. BLES+CATH-2 mixtures had no significantly different minimum surface tension versus the BLES control. Compared to the other cathelicidins, CATH-2 retained the most bactericidal activity in the presence of BLES. The BLES+CATH-2 mixture appears to be an optimal surfactant-AMP mixture based on in vitro assays. Future directions involve investigating the potential of this mixture in animal models of bacterial pneumonia. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  19. Chlorhexidine with or without alcohol against biofilm formation: efficacy, adverse events and taste preference

    Directory of Open Access Journals (Sweden)

    Gabriela Otero dos SANTOS

    2017-05-01

    Full Text Available Abstract In recent years, different chlorhexidine formulations have been tested, including an alcohol-free alternative, but the effect of this solution on early biofilm formation is not clear. A crossover, randomized, double-blind clinical trial was conducted to evaluate the effect of two chlorhexidine solutions against supra- and subgingival biofilm formation (NCT#02656251. Thirty-five participants were randomized and asked to rinse twice daily with 15 ml of an alcohol-containing 0.12% chlorhexidine solution, an alcohol-free 0.12% chlorhexidine solution, or placebo. The study was conducted in three experimental periods of 4 days each, with a 10-day washout between the periods. All the experimental periods followed the same protocol, except that the solutions were switched. Biofilm distribution was evaluated every 24 hours by the Plaque-Free Zone Index, during 96 hours. Adverse events were self-reported and sensory evaluation was performed using a hedonic scale. Compared to the placebo, the chlorhexidine solutions resulted in a significantly higher number of surfaces free of plaque over 96 hours (p < 0.01, and were able to prevent subgingival biofilm formation (p < 0.01. The alcohol-free chlorhexidine solution was associated with a lower incidence of adverse events, compared with alcohol-containing chlorhexidine (p < 0.05; it also received better sensory evaluation and acceptance by trial participants, compared with the alcohol-containing chlorhexidine (p = 0.007, and had a similar inhibitory effect on the formation of supra- and subgingival biofilms.

  20. Antimicrobial Peptides in Biomedical Device Manufacturing

    Directory of Open Access Journals (Sweden)

    Martijn Riool

    2017-08-01

    Full Text Available Over the past decades the use of medical devices, such as catheters, artificial heart valves, prosthetic joints, and other implants, has grown significantly. Despite continuous improvements in device design, surgical procedures, and wound care, biomaterial-associated infections (BAI are still a major problem in modern medicine. Conventional antibiotic treatment often fails due to the low levels of antibiotic at the site of infection. The presence of biofilms on the biomaterial and/or the multidrug-resistant phenotype of the bacteria further impair the efficacy of antibiotic treatment. Removal of the biomaterial is then the last option to control the infection. Clearly, there is a pressing need for alternative strategies to prevent and treat BAI. Synthetic antimicrobial peptides (AMPs are considered promising candidates as they are active against a broad spectrum of (antibiotic-resistant planktonic bacteria and biofilms. Moreover, bacteria are less likely to develop resistance to these rapidly-acting peptides. In this review we highlight the four main strategies, three of which applying AMPs, in biomedical device manufacturing to prevent BAI. The first involves modification of the physicochemical characteristics of the surface of implants. Immobilization of AMPs on surfaces of medical devices with a variety of chemical techniques is essential in the second strategy. The main disadvantage of these two strategies relates to the limited antibacterial effect in the tissue surrounding the implant. This limitation is addressed by the third strategy that releases AMPs from a coating in a controlled fashion. Lastly, AMPs can be integrated in the design and manufacturing of additively manufactured/3D-printed implants, owing to the physicochemical characteristics of the implant material and the versatile manufacturing technologies compatible with antimicrobials incorporation. These novel technologies utilizing AMPs will contribute to development of novel

  1. A novel chimeric peptide with antimicrobial activity.

    Science.gov (United States)

    Alaybeyoglu, Begum; Akbulut, Berna Sariyar; Ozkirimli, Elif

    2015-04-01

    Beta-lactamase-mediated bacterial drug resistance exacerbates the prognosis of infectious diseases, which are sometimes treated with co-administration of beta-lactam type antibiotics and beta-lactamase inhibitors. Antimicrobial peptides are promising broad-spectrum alternatives to conventional antibiotics in this era of evolving bacterial resistance. Peptides based on the Ala46-Tyr51 beta-hairpin loop of beta-lactamase inhibitory protein (BLIP) have been previously shown to inhibit beta-lactamase. Here, our goal was to modify this peptide for improved beta-lactamase inhibition and cellular uptake. Motivated by the cell-penetrating pVEC sequence, which includes a hydrophobic stretch at its N-terminus, our approach involved the addition of LLIIL residues to the inhibitory peptide N-terminus to facilitate uptake. Activity measurements of the peptide based on the 45-53 loop of BLIP for enhanced inhibition verified that the peptide was a competitive beta-lactamase inhibitor with a K(i) value of 58 μM. Incubation of beta-lactam-resistant cells with peptide decreased the number of viable cells, while it had no effect on beta-lactamase-free cells, indicating that this peptide had antimicrobial activity via beta-lactamase inhibition. To elucidate the molecular mechanism by which this peptide moves across the membrane, steered molecular dynamics simulations were carried out. We propose that addition of hydrophobic residues to the N-terminus of the peptide affords a promising strategy in the design of novel antimicrobial peptides not only against beta-lactamase but also for other intracellular targets. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.

  2. Antimicrobial Peptides in Biomedical Device Manufacturing

    Science.gov (United States)

    Riool, Martijn; de Breij, Anna; Drijfhout, Jan W.; Nibbering, Peter H.; Zaat, Sebastian A. J.

    2017-08-01

    Over the past decades the use of medical devices, such as catheters, artificial heart valves, prosthetic joints and other implants, has grown significantly. Despite continuous improvements in device design, surgical procedures and wound care, biomaterial-associated infections (BAI) are still a major problem in modern medicine. Conventional antibiotic treatment often fails due to the low levels of antibiotic at the site of infection. The presence of biofilms on the biomaterial and/or the multidrug-resistant phenotype of the bacteria further impair the efficacy of antibiotic treatment. Removal of the biomaterial is then the last option to control the infection. Clearly, there is a pressing need for alternative strategies to prevent and treat BAI. Synthetic antimicrobial peptides (AMPs) are considered promising candidates as they are active against a broad spectrum of (antibiotic-resistant) planktonic bacteria and biofilms. Moreover, bacteria are less likely to develop resistance to these rapidly-acting peptides. In this review we highlight the four main strategies, three of which applying AMPs, in biomedical device manufacturing to prevent BAI. The first involves modification of the physicochemical characteristics of the surface of implants. Immobilization of AMPs on surfaces of medical devices with a variety of chemical techniques is essential in the second strategy. The main disadvantage of these two strategies relates to the limited antibacterial effect in the tissue surrounding the implant. This limitation is addressed by the third strategy that releases AMPs from a coating in a controlled fashion. Lastly, AMPs can be integrated in the design and manufacturing of additively manufactured / 3D-printed implants, owing to the physicochemical characteristics of the implant material and the versatile manufacturing technologies compatible with antimicrobials incorporation. These novel technologies utilizing AMPs will contribute to development of novel and safe

  3. No Clear Benefit of Chlorhexidine Use at Home Before Surgical Preparation

    Science.gov (United States)

    Jegede, Kolawole; Lombardi, Joseph; Whittier, Susan; Gorroochurn, Prakash; Lehman, Ronald A.; Riew, K. Daniel

    2018-01-01

    Introduction: Several studies have evaluated the efficacy of home use of chlorhexidine before surgery to reduce bacterial colonization. However, these studies have provided conflicting evidence about the potential efficacy of this strategy in decreasing bacterial loads and infection rates across surgical populations, and no prior study has analyzed the benefit of this intervention before spine surgery. We prospectively analyzed the effectiveness of chlorhexidine gluconate wipes for decreasing bacterial counts on the posterior neck. Methods: Sixteen healthy adults participated in this prospective study. The right side of each participant’s neck was wiped twice (the night before and the morning of the experiment) with chlorhexidine gluconate wipes. The left side was used as the control region. Bacterial swabs were obtained as a baseline upon enrollment in the study, then upon arrival at the hospital, and, finally, after both sides of the neck had received standard preoperative scrubbing. Results: All patients had positive baseline bacterial growth (median >1,000 colonies/mL). When chlorhexidine gluconate wipes were used, decreased bacterial counts were noted before the preoperative scrub, but this finding was not statistically significant (P = 0.059). All patients had zero bacteria identified on either side of their neck after completion of the preoperative scrub. Conclusion: At-home use of chlorhexidine gluconate wipes did not decrease the topical bacterial burden. Therefore, using chlorhexidine gluconate wipes at home before surgery may offer no added benefit. PMID:29227322

  4. Inhibition effect of calcium hydroxide point and chlorhexidine point on root canal bacteria of necrosis teeth

    Directory of Open Access Journals (Sweden)

    Andry Leonard Je

    2006-03-01

    Full Text Available Calcium Hydroxide point and Chlorhexidine point are new drugs for eliminating bacteria in the root canal. The points slowly and controly realease Calcium Hydroxide and Chlorhexidine into root canal. The purpose of the study was to determined the effectivity of Calcium hydroxide point (Calcium hydroxide plus point and Chlorhexidine point in eleminating the root canal bacteria of nescrosis teeth. In this study 14 subjects were divided into 2 groups. The first group was treated with Calcium hydroxide point and the second was treated with Chlorhexidine poin. The bacteriological sampling were measured with spectrofotometry. The Paired T Test analysis (before and after showed significant difference between the first and second group. The Independent T Test which analysed the effectivity of both groups had not showed significant difference. Although there was no significant difference in statistical test, the result of second group eliminate more bacteria than the first group. The present finding indicated that the use of Chlorhexidine point was better than Calcium hydroxide point in seven days period. The conclusion is Chlorhexidine point and Calcium hydroxide point as root canal medicament effectively eliminate root canal bacteria of necrosis teeth.

  5. Using a Systems Engineering Initiative for Patient Safety to Evaluate a Hospital-wide Daily Chlorhexidine Bathing Intervention.

    Science.gov (United States)

    Caya, Teresa; Musuuza, Jackson; Yanke, Eric; Schmitz, Michelle; Anderson, Brooke; Carayon, Pascale; Safdar, Nasia

    2015-01-01

    We undertook a systems engineering approach to evaluate housewide implementation of daily chlorhexidine bathing. We performed direct observations of the bathing process and conducted provider and patient surveys. The main outcome was compliance with bathing using a checklist. Fifty-seven percent of baths had full compliance with the chlorhexidine bathing protocol. Additional time was the main barrier. Institutions undertaking daily chlorhexidine bathing should perform a rigorous assessment of implementation to optimize the benefits of this intervention.

  6. Antibacterial efficacy and effect of chlorhexidine mixed with irreversible hydrocolloid for dental impressions: a randomized controlled trial.

    Science.gov (United States)

    Cubas, Glória; Valentini, Fernanda; Camacho, Guilherme Brião; Leite, Fábio; Cenci, Maximiliano Sérgio; Pereira-Cenci, Tatiana

    2014-01-01

    This study aimed to evaluate whether chlorhexidine mixed with irreversible hydrocolloid powder decreases microbial contamination during impression taking without affecting the resulting casts. Twenty volunteers were randomly divided into two groups (n = 10) according to the liquid used for impression taking in conjunction with irreversible hydrocolloid: 0.12% chlorhexidine or water. Surface roughness and dimensional stability of the casts were evaluated. Chlorhexidine mixed with irreversible hydrocolloid decreased the percentage of microorganisms when compared with water (P impression quality.

  7. Screening of antimicrobial activity of macroalgae extracts from the Moroccan Atlantic coast.

    Science.gov (United States)

    El Wahidi, M; El Amraoui, B; El Amraoui, M; Bamhaoud, T

    2015-05-01

    The aim of this work is the screening of the antimicrobial activity of seaweed extracts against pathogenic bacteria and yeasts. The antimicrobial activity of the dichloromethane and ethanol extracts of ten marine macroalgae collected from the Moroccan's Atlantic coast (El-Jadida) was tested against two Gram+ (Bacillus subtilis and Staphylococcus aureus) and two Gram- (Escherichia coli and Pseudomonas aeruginosa) human pathogenic bacteria, and against two pathogenic yeasts (Candida albicans and Cryptococcus neoformans) using the agar disk-diffusion method. Seven algae (70%) of ten seaweeds are active against at least one pathogenic microorganisms studied. Five (50%) are active against the two studied yeast with an inhibition diameter greater than 15 mm for Cystoseira brachycarpa. Six (60%) seaweeds are active against at least one studied bacteria with five (50%) algae exhibiting antibacterial inhibition diameter greater than 15 mm. Cystoseira brachycarpa, Cystoseira compressa, Fucus vesiculosus, and Gelidium sesquipedale have a better antimicrobial activity with a broad spectrum antimicrobial and are a potential source of antimicrobial compounds and can be subject of isolation of the natural antimicrobials. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  8. Bioprospecting saline gradient of a Wildlife Sanctuary for bacterial diversity and antimicrobial activities.

    Science.gov (United States)

    DeLuca, Mara; King, Riley; Morsy, Mustafa

    2017-08-11

    Antibiotic-resistant bacteria are becoming a global crisis, causing death of thousands of people and significant economic impact. The discovery of novel antibiotics is crucial to saving lives and reducing healthcare costs. To address the antibiotic-resistant crisis, in collaboration the Small World Initiative, which aims to crowdsource novel antibiotic discovery, this study aimed to identify antimicrobial producing bacteria and bacterial diversity in the soil of the Stimpson Wildlife Sanctuary, an inland area with a soil salt gradient. Approximately 4500 bacterial colonies were screened for antimicrobial activity and roughly 100 bacteria were identified as antimicrobial producers, which belong to Entrococcaceae (74%), Yersiniaceae (19%), and unidentified families (7%). Several bacterial isolates showed production of broad spectrum inhibitory compounds, while others were more specific to certain pathogens. The data obtained from the current study provide a resource for further characterization of the soil bacteria with antimicrobial activity, with an aim to discover novel ones. The study showed no correlation between soil salt level and the presence of bacteria with antimicrobial activities. However, most of the identified antimicrobial producing bacteria do not belong to actinomycetes, the most common phyla of antibiotic producing bacteria and this could potentially lead to the discovery of novel antibiotics.

  9. A molecular dynamics and circular dichroism study of a novel synthetic antimicrobial peptide

    International Nuclear Information System (INIS)

    Rodina, N P; Yudenko, A N; Terterov, I N; Eliseev, I E

    2013-01-01

    Antimicrobial peptides are a class of small, usually positively charged amphiphilic peptides that are used by the innate immune system to combat bacterial infection in multicellular eukaryotes. Antimicrobial peptides are known for their broad-spectrum antimicrobial activity and thus can be used as a basis for a development of new antibiotics against multidrug-resistant bacteria. The most challengeous task on the way to a therapeutic use of antimicrobial peptides is a rational design of new peptides with enhanced activity and reduced toxicity. Here we report a molecular dynamics and circular dichroism study of a novel synthetic antimicrobial peptide D51. This peptide was earlier designed by Loose et al. using a linguistic model of natural antimicrobial peptides. Molecular dynamics simulation of the peptide folding in explicit solvent shows fast formation of two antiparallel beta strands connected by a beta-turn that is confirmed by circular dichroism measurements. Obtained from simulation amphipatic conformation of the peptide is analysed and possible mechanism of it's interaction with bacterial membranes together with ways to enhance it's antibacterial activity are suggested

  10. An endogenous ribonuclease inhibitor regulates the antimicrobial activity of ribonuclease 7 in the human urinary tract

    Science.gov (United States)

    Spencer, John David; Schwaderer, Andrew L.; Eichler, Tad; Wang, Huanyu; Kline, Jennifer; Justice, Sheryl S.; Cohen, Daniel M.; Hains, David S.

    2013-01-01

    Recent studies stress the importance of antimicrobial peptides in protecting the urinary tract from infection. Previously, we have shown that ribonuclease 7 (RNase 7) is a potent antimicrobial peptide that has broad-spectrum antimicrobial activity against uropathogenic bacteria. The urothelium of the lower urinary tract and intercalated cells of the kidney produce RNase 7 but regulation of its antimicrobial activity has not been well defined. Here we characterize the expression of an endogenous inhibitor, ribonuclease inhibitor (RI), in the urinary tract and evaluate its effect on RNase 7’s antimicrobial activity. Using RNA isolated from non-infected human bladder and kidney tissue, quantitative real-time PCR showed that RNH1, the gene encoding RI, is constitutively expressed throughout the urinary tract. With pyelonephritis, RNH1 expression and RI peptide production significantly decrease. Immunostaining localized RI production to the umbrella cells of the bladder and intercalated cells of the renal collecting tubule. In vitro assays showed that RI bound to RNase 7 and suppressed its antimicrobial activity by blocking its ability to bind the cell wall of uropathogenic bacteria. Thus, these results demonstrate a new immunomodulatory role for RI and identified a unique regulatory pathway that may affect how RNase 7 maintains urinary tract sterility. PMID:24107847

  11. Microbiological aspects of an in situ model to study effects of antimicrobial agents on dental plaque ecology.

    Science.gov (United States)

    Giertsen, E; Guggenheim, B; Thurnheer, T; Gmür, R

    2000-10-01

    This study validates an in situ model for ecological studies of dental plaque exposed to various antimicrobial agents with different modes of action on plaque bacteria. Eleven subjects wore two acrylic appliances, each containing two bovine enamel discs, during two 1-wk test periods. Using a split-mouth crossover design, the appliances were dipped twice daily for 1 min into water (control; treatment A), fluoride (26.3 mM NaF; B), zinc acetate (20.0 mM; C), or fluoride plus zinc acetate (D). Four of the subjects used also chlorhexidine diacetate (2.2 mM; E) and chlorhexidine plus fluoride (F). At the end of each period, plaque was collected from the discs, after which the microbiota were analyzed by culture, automated quantitative immunofluorescence, and a viability fluorescence stain. As compared to control, treatments B, C, and D resulted in a significant reduction of individual taxa as detected by immunofluorescence, whereas similar bacterial viability and total bacterial numbers were observed. In contrast, chlorhexidine significantly reduced bacterial viability, total cell numbers, and the abundance of most of the enumerated taxa. We conclude that this in situ model is well suited to study effects of antimicrobial agents on dental plaque ecology. Combined with viability testing, immunofluorescence is obviously superior to culture in detecting taxa-specific shifts caused by antimicrobial agents.

  12. Sequence-specific antimicrobials using efficiently delivered RNA-guided nucleases.

    Science.gov (United States)

    Citorik, Robert J; Mimee, Mark; Lu, Timothy K

    2014-11-01

    Current antibiotics tend to be broad spectrum, leading to indiscriminate killing of commensal bacteria and accelerated evolution of drug resistance. Here, we use CRISPR-Cas technology to create antimicrobials whose spectrum of activity is chosen by design. RNA-guided nucleases (RGNs) targeting specific DNA sequences are delivered efficiently to microbial populations using bacteriophage or bacteria carrying plasmids transmissible by conjugation. The DNA targets of RGNs can be undesirable genes or polymorphisms, including antibiotic resistance and virulence determinants in carbapenem-resistant Enterobacteriaceae and enterohemorrhagic Escherichia coli. Delivery of RGNs significantly improves survival in a Galleria mellonella infection model. We also show that RGNs enable modulation of complex bacterial populations by selective knockdown of targeted strains based on genetic signatures. RGNs constitute a class of highly discriminatory, customizable antimicrobials that enact selective pressure at the DNA level to reduce the prevalence of undesired genes, minimize off-target effects and enable programmable remodeling of microbiota.

  13. Small cationic antimicrobial peptidomimetics: emerging candidate for the development of potential anti-infective agents.

    Science.gov (United States)

    Lohan, Sandeep; Bisht, Gopal Singh

    2013-01-01

    Rapid increase in the emergence and spread of microbes resistant to conventionally used antibiotics has become a major threat to global health care. Antimicrobial peptides (AMPs) are considered as a potential source of novel antibiotics because of their numerous advantages such as broad-spectrum activity, lower tendency to induce resistance, immunomodulatory response and unique mode of action. However, AMPs have several drawbacks such as; susceptibility to protease degradation, toxicity and high costs of manufacturing. Therefore, extensive research efforts are underway to explore the therapeutic potential of these fascinating natural compounds. This review highlights the potential of small cationic antimicrobial peptidomimetics (SCAMPs; M.W. ≅ 700 Da) as new generation antibiotics. In particular, we focused on recently identified small active pharmacophore from bulky templates of native AMPs, β-peptides, and lipopeptides. In addition, various design strategies recently undertaken to improve the physicochemical properties (proteolytic stability & plasma protein binding) of small cationic peptides have also been discussed.

  14. Antimicrobial evaluation of the crude extract of symbiotic fungi from marine sponge Reniera japonica

    Directory of Open Access Journals (Sweden)

    Xuelian Bai

    2018-05-01

    Full Text Available Marine sponge-derived microbes are one of the rich sources of bioactive natural products with a broad spectrum of bioactivities. The present work focuses on the isolation and antimicrobial screening of the marine sponge-associated fungi from Reniera japonica MNP-2016. The results indicated that five fungi (L1-2, L2-1, L4, L8-1 and L14 were successfully isolated. Bioassay tests showed that only strain L14 had strong inhibitory effect on the pathogens, Staphyloccocus aureus, Escherichia coli and Candida albicans. 18S rDNA sequence analysis indicated that strain L14 was ascribed to Aspergillus genus. To the best of our knowledge, this work was the first report on the isolation and antimicrobial evaluation of fungi from R. japonica.

  15. Chitosan-thioglycolic acid as a versatile antimicrobial agent.

    Science.gov (United States)

    Geisberger, Georg; Gyenge, Emina Besic; Hinger, Doris; Käch, Andres; Maake, Caroline; Patzke, Greta R

    2013-04-08

    As functionalized chitosans hold great potential for the development of effective and broad-spectrum antibiotics, representative chitosan derivatives were tested for antimicrobial activity in neutral media: trimethyl chitosan (TMC), carboxy-methyl chitosan (CMC), and chitosan-thioglycolic acid (TGA; medium molecular weight: MMW-TGA; low molecular weight: LMW-TGA). Colony forming assays indicated that LMW-TGA displayed superior antimicrobial activity over the other derivatives tested: a 30 min incubation killed 100% Streptococcus sobrinus (Gram-positive bacteria) and reduced colony counts by 99.99% in Neisseria subflava (Gram-negative bacteria) and 99.97% in Candida albicans (fungi). To elucidate LMW-TGA effects at the cellular level, microscopic studies were performed. Use of fluorescein isothiocyanate (FITC)-labeled chitosan derivates in confocal microscopy showed that LMW-TGA attaches to microbial cell walls, while transmission electron microscopy indicated that this derivative severely affects cell wall integrity and intracellular ultrastructure in all species tested. We therefore propose LMW-TGA as a promising and effective broad-band antimicrobial compound.

  16. Avian Antimicrobial Host Defense Peptides: From Biology to Therapeutic Applications

    Directory of Open Access Journals (Sweden)

    Guolong Zhang

    2014-02-01

    Full Text Available Host defense peptides (HDPs are an important first line of defense with antimicrobial and immunomoduatory properties. Because they act on the microbial membranes or host immune cells, HDPs pose a low risk of triggering microbial resistance and therefore, are being actively investigated as a novel class of antimicrobials and vaccine adjuvants. Cathelicidins and β-defensins are two major families of HDPs in avian species. More than a dozen HDPs exist in birds, with the genes in each HDP family clustered in a single chromosomal segment, apparently as a result of gene duplication and diversification. In contrast to their mammalian counterparts that adopt various spatial conformations, mature avian cathelicidins are mostly α-helical. Avian β-defensins, on the other hand, adopt triple-stranded β-sheet structures similar to their mammalian relatives. Besides classical β-defensins, a group of avian-specific β-defensin-related peptides, namely ovodefensins, exist with a different six-cysteine motif. Like their mammalian counterparts, avian cathelicidins and defensins are derived from either myeloid or epithelial origin expressed in a majority of tissues with broad-spectrum antibacterial and immune regulatory activities. Structure-function relationship studies with several avian HDPs have led to identification of the peptide analogs with potential for use as antimicrobials and vaccine adjuvants. Dietary modulation of endogenous HDP synthesis has also emerged as a promising alternative approach to disease control and prevention in chickens.

  17. Antimicrobial polymers.

    Science.gov (United States)

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

    2014-12-01

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

  18. Removal of Escherichia coli and Enterococcus faecalis after Hand Washing with Antimicrobial and Nonantimicrobial Soap and Persistence of These Bacteria in Rinsates.

    Science.gov (United States)

    Pérez-Garza, J; García, S; Heredia, N

    2017-10-01

    Food handlers are important sources of contamination in the agricultural environment. This study was conducted (i) to evaluate the activity of antimicrobial soaps against Escherichia coli and Enterococcus faecalis using a hand washing model with soiled hands and (ii) to determine the survival and persistence of these bacteria in rinsates. Sterilized agricultural soil from tomato and pepper farms was inoculated with E. coli or E. faecalis at 10 3 or 10 6 CFU/g. Decontaminated hands were placed in contact with contaminated soil for 2 min and were then washed with soaps with or without antimicrobial compounds (citric extracts, chloroxylenol, triclosan, or chlorhexidine gluconate). As the control, hands were washed with sterile distilled water. The levels of bacteria remaining on the hands and recovered from the rinsates were determined using a membrane filtration method and selective media. Antimicrobial soaps removed levels of E. coli similar to those removed by distilled water and nonantimicrobial soap on hands contaminated with E. coli at 10 3 CFU/g. However, when hands were contaminated with E. coli at 10 6 CFU/g, more E. coli was removed with the chlorhexidine gluconate soap. When hands were contaminated with E. faecalis at 10 3 CFU/g, bacteria were removed more effectively with soaps containing chloroxylenol or chlorhexidine gluconate. When hands were contaminated with E. faecalis at 10 6 CFU/g, all of the antimicrobial soaps were more effective for removing the bacteria than were distilled water and nonantimicrobial soap. E. coli grew in all of the hand washing rinsates except that containing triclosan, whereas E. faecalis from the 10 6 CFU/g treatments grew in rinsates containing chlorhexidine gluconate and in the distilled water rinsates. Washing with antimicrobial soap was more effective for reducing bacteria on soiled hands than was washing with water or nonantimicrobial soap. However, persistence or growth of bacteria in these rinsates poses health risks.

  19. Chlorhexidine rinse for prevention of urethritis in men linked to oral sex

    Directory of Open Access Journals (Sweden)

    Kolahi Jafar

    2010-06-01

    Full Text Available Abstract Background Oral sex among teenagers is on the rise. Similarity between the oral flora and organisms recovered from nongonococcal urethritis and prostatitis, points to retrograde entry of bacteria from oral cavity into the urethra following insertive oral intercourse. Presentation of the hypothesis Chlorhexidine has a wide spectrum of anti-bactericidal activity encompassing gram positive and negative bacteria. It is also effective against HIV and HBV. It produced large and prolonged reductions in salivary bacterial counts within 7-h of its use. Hence, it would seem logic to postulate that rinsing with chlorhexidine before oral sex will be effective for prevention of retrograde entry of bacteria from oral cavity into the urethra. The recommendation for rinsing will be: 15 ml of a 0.12% or 10 ml of 0.2% chlorhexidine rinse for 30 seconds. Also other drug delivery systems such as chlorhexidine chewing gum or spray can be used. Testing the hypothesis Men suffering from recurrent nongonococcal urethritis or prostatitis are good subjects for testing the hypothesis. They perform genital safe sex via consistent use of condom. Yet they generally received unprotected insertive oral intercourse. Chlorhexidine can be used for prevention of recurrences of the disease. Implications of the hypothesis The chlorhexidine will be a new, easy, attractive and effective method for reduction of nongonococcal urethritis, prostatitis and epidydimitis following insertive oral intercourse. It is poorly absorbed from skin, mucosa and gastrointestinal tract indicating systemic safety of chlorhexidine. The agent does not cause any bacterial resistance and supra-infection.

  20. Efficacy of chlorhexidine gluconate ointment (Oronine H® for experimentally-induced comedones

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    Yamakoshi T

    2012-07-01

    Full Text Available Takako Yamakoshi,1 Teruhiko Makino,1 Kenji Matsunaga,1 Yoko Yoshihisa,1 Mati Ur Rehman,1 Taisuke Seki,2 Yoshito Hayashi,3 Tadamichi Shimizu11Department of Dermatology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama-shi, Toyama; 2Seki Dermatological Clinic, Toyama-shi, Toyama; 3Otsuka Pharmaceutical Factory Inc, Naruto-shi, Tokushima, JapanBackground: Oronine H® ointment, which contains chlorhexidine gluconate as its active component, is a well known disinfectant, and has been widely used for treatment of acne in Japan. In this study, we investigated the inhibitory effect of this ointment on the formation of comedones induced by application of 50% oleic acid on the orifices of the external auditory canals of rabbits.Methods: The application sites were observed with a dermatoscope, and the area of the hair pores was measured using an Image analysis software program.Results: The chlorhexidine gluconate ointment inhibited comedone formation significantly more effectively than the liquid paraffin used as a control (P < 0.001. We also investigated the therapeutic effect of this ointment on comedones. After starting application of chlorhexidine gluconate ointment or liquid paraffin on the comedone area, the hair pore size was gradually decreased in the group treated with chlorhexidine gluconate ointment compared with the hair pore size at baseline.Conclusion: These results suggest that chlorhexidine gluconate ointment is effective for inhibiting comedone formation as well as for treating already formed comedones. Chlorhexidine gluconate ointment is a useful topical medicine for the treatment of early-stage acne and for preventing acne.Keywords: chlorhexidine gluconate ointment, comedones, dermatoscope, oleic acid

  1. Antimicrobial peptides: Possible anti-infective agents.

    Science.gov (United States)

    Lakshmaiah Narayana, Jayaram; Chen, Jyh-Yih

    2015-10-01

    Multidrug-resistant bacterial, fungal, viral, and parasitic infections are major health threats. The Infectious Diseases Society of America has expressed concern on the decrease of pharmaceutical companies working on antibiotic research and development. However, small companies, along with academic research institutes, are stepping forward to develop novel therapeutic methods to overcome the present healthcare situation. Among the leading alternatives to current drugs are antimicrobial peptides (AMPs), which are abundantly distributed in nature. AMPs exhibit broad-spectrum activity against a wide variety of bacteria, fungi, viruses, and parasites, and even cancerous cells. They also show potential immunomodulatory properties, and are highly responsive to infectious agents and innate immuno-stimulatory molecules. In recent years, many AMPs have undergone or are undergoing clinical development, and a few are commercially available for topical and other applications. In this review, we outline selected anion and cationic AMPs which are at various stages of development, from preliminary analysis to clinical drug development. Moreover, we also consider current production methods and delivery tools for AMPs, which must be improved for the effective use of these agents. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Comparative evaluation of honey, chlorhexidine gluconate (0.2% and combination of xylitol and chlorhexidine mouthwash (0.2% on the clinical level of dental plaque: A 30 days randomized control trial

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    Ankita Jain

    2015-01-01

    Full Text Available Aim: To compare the effect of honey, chlorhexidine mouthwash and combination of xylitol chewing gum and chlorhexidine mouthwash on the dental plaque level. Materials and Methods: Ninety healthy dental students, both male and female, aged between 21 to 25 years participated in the study. The subjects were randomly divided into three groups, i.e. the honey group, the chlorhexidine gluconate mouthwash group and the combination of xylitol chewing gum and chlorhexidine (CHX mouthwash group. The data was collected at the baseline, 15 th day and 30 th day; the plaque was disclosed using disclosing solution and their scores were recorded at six sites per tooth using the Quigley and Hein plaque index modified by Turesky-Gilmore-Glickman. Statistical analysis was carried out later to compare the effect of all the three groups. P ≤ 0.05 was considered as statistically significant. Results: Our result showed that all the three groups were effective in reducing the plaque but post-hoc LSD (Least Significant Difference showed that honey group and chlorhexidine + xylitol group were more effective than chlorhexidine group alone. The results demonstrated a significant reduction of plaque indices in honey group and chlorhexidine + xylitol group over a period of 15 and 30 days as compared to chlorhexidine.

  3. Antibacterial efficacy of chlorhexidine gluconate intracanal medication in vivo.

    Science.gov (United States)

    Paquette, Lisane; Legner, Milos; Fillery, Edward D; Friedman, Shimon

    2007-07-01

    The antibacterial efficacy of intracanal medication with 2% chlorhexidine liquid (CHX) was assessed in teeth with apical periodontitis. Canals in 22 teeth were instrumented at the first session, medicated with CHX, and reaccessed after 7 to 15 days. Bacteriological samples were aspirated at the first and second sessions, before (1A, 2A) and after (1B, 2B) canal instrumentation. Viable bacterial counts were obtained by culture (CFU) and microscopy using vital dyes. Microscopic counts were higher than CFU counts. Consistently high CFU counts in 1A samples (mean, 2 x 10(5) microL(-1) canal volume) decreased significantly (p < 0.0001) in 1B samples, increased significantly (p < 0.04) in 2A samples, and decreased in 2B samples to the level of 1B samples. Proportions of negative cultures followed the pattern of CFU counts. Intracanal medication with CHX did not reduce the bacterial concentration. Bacterial counts expressed per microliter canal volume added information beyond the counts per tooth as expressed in previous studies.

  4. Evaluation of chlorhexidine gluconate mouthrinse-induced staining using a digital colorimeter: an in vivo study.

    Science.gov (United States)

    Bagis, Bora; Baltacioglu, Esra; Özcan, Mutlu; Ustaomer, Seda

    2011-03-01

    To investigate the persistence of staining after the use of chlorhexidine gluconate mouthrinse. Twenty-four subjects (nine women and 15 men) who underwent periodontal therapy and were prescribed the use of 0.2% chlorhexidine gluconate mouthrinse participated in this study. Color values of maxillary central incisors, canines, and first molars were recorded at baseline; 3 days; and 1, 2, and 3 weeks of twice-daily chlorhexidine gluconate use with a digital intraoral colorimeter according to the CIE L*a*b* coordinates. While color-change (Delta E) values showed significant differences (P=.020) at different time points (10.1, 8.9, 8.9, 9.4, after 3 days and 1, 2, and 3 weeks, respectively), the duration of chlorhexidine gluconate use did not significantly affect the results (P=.873) (two-way ANOVA, Tukey test). No significant difference was found among Delta L* (P=.070), Delta a* (P=.169), and Delta b* (P=.691) values at any time point (one-way ANOVA). Measurements of baseline to day 3 differences showed significantly higher Delta E values than those at other time points (P.05) (Tukey test). The highest visible staining occurred on the first molars at all time points (83%, 79%, 79%, and 96% after 3 days and 1, 2, and 3 weeks, respectively) compared to the other teeth evaluated. The staining effect of chlorhexidine gluconate mouthrinse on natural dentition should be expected to be the highest in the first few days of use.

  5. Efficacy of a probiotic and chlorhexidine mouth rinses: A short-term clinical study

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    Harini P

    2010-09-01

    Full Text Available Introduction: Probiotic technology represents a breakthrough approach to maintaining oral health by utilizing natural beneficial bacteria commonly found in healthy mouths to provide a natural defense against those bacteria thought to be harmful to teeth and gums. However, data are still sparse on the probiotic action in the oral cavity. The review article on probiotics in children published by Twetman and Stecksen- Blicks in 2008 showed only one study of dental interest on probiotics in children. Aim and Objectives: The present study evaluated clinically the efficacy of a probiotic and chlorhexidine mouth rinses on plaque and gingival accumulation in children. The trial design is a double-blind parallel group, 14 days comparative study between a probiotic mouth rinse and a chlorhexidine mouth rinse, which included 45 healthy children in the age group of 6-8 years. Results: The Probiotic and Chlorhexidine groups had less plaque accumulations compared with the Control group at the end of 14 years (P < 0.001 and P < 0.001, respectively. But, unlike the plaque score, there was a significant difference in the Gingival Index between the Probiotic and the Chlorhexidine groups (P = 0.009, Probiotic group being better than the Chlorhexidine group (mean = 0.2300 and 0.6805, respectively. Conclusion: The Probiotic mouth rinse was found effective in reducing plaque accumulation and gingival inflammation. Therefore, probiotic mouth rinse obviously has a potential therapeutic value and further long-term study is recommended to determine its efficacy.

  6. Microbiological aspects of the effectiveness of antimicrobial drugs

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    Oleksandr Nazarchuk

    2015-06-01

      Abstract Introduction. It is well known, that patients with deep burns belong to the category of critically ill ones. According to the data of National Nosocomial Infections Surveillance (2004, Staphylococcus spp. are among leading opportunistic pathogens of infectious complications in such patients. Nowadays much attention is given to the problem of antibiotic resistance of Staphylococcus clinical strains. More often antiseptics are used in treatment of infectious complications, caused by antibiotic resistant miсroorganisms. The aim of the research was to study microbiological aspects of the effectiveness of antimicrobial drugs. Materials and methods. There were examined 372 critically ill patients with burns, having infectious complications. In all patients microbiological examinations were carried out during the first 7 days after burn trauma. There were isolated 115 clinical strains of Staphylococcus spp.. Their morphological, cultural, biochemical qualities and sensitivity to antibiotics, antiseptics were studied. Rresults of the study. We found, that clinical strains of S. aureus, S. epidermidis were highly resistant to oxacillin (46,9; 59,1 % respectively; were insensitive to clavulanate and sulbactam potentiated beta-lactams; ceftriaxone; meropenem, imipenem; ciprofloxacin. Sensitivity of Staphylococcus to amikacin, linezolid, vancomycin was found. There was shown the sensitivity of antibiotic resistant strains of Staphylococcus to decamethoxin, its polymer composition, chlorhexidine digluconate. In the research there was proved the decreasing of the effectiveness of chlorhexidine digluconate against Staphylococcus in conditions of increasing microbial load to 109 CFU/ml in 6,6 times comparably to decamethoxin drugs (p<0,001. Conclusions Resistant to the majority of antibiotics strains of Staphylococcus spp. store their high sensitivity to antiseptic decamethoxin and its polymeric composition, chlorhexidine digluconate. Microbial load increase up to 109

  7. Comparing the effects of chlorhexidine and persica on alveolar bone healing following tooth extraction in rats, a randomised controlled trial.

    Science.gov (United States)

    Dorri, Mojtaba; Shahrabi, Shokufeh; Navabazam, Alireza

    2012-02-01

    Chlorhexidine is broadly prescribed by clinicians for treating extraction socket wounds; however, studies have reported adverse effects for chlorhexidine. Persica, a herbal antibacterial agent, could be an alternative for chlorhexidine. The aim of this randomised controlled trial was to investigate the effects of persica and chlorhexidine on alveolar bone healing following tooth extraction in rats. Eighteen Wistar rats were randomly allocated to three study groups: 0.2% chlorhexidine, 10% persica and controls (tap water). The rats were mouth-rinsed for 14 days. On day 8, the mandibular right first molars of all the rats were extracted. On day 21, the rats were euthanized and histological slides of their extraction sockets were prepared. The amount of new bone formation and the number of inflammatory cells in the extraction socket for each rat were recorded. Data were analysed using linear regression and Mann-Whitney tests. There was no significant difference between the control group and the intervention groups in terms of new bone formation and inflammatory cell count. The mean new bone formation was significantly higher in the persica group than in the chlorhexidine group. There was a significant association between new bone formation and inflammatory cell count in the entire sample. In conclusion, there were no significant differences between rinsing with tap water and rinsing with 0.2% chlorhexidine and 10% persica in enhancing extraction socket wound healing in rats. Extraction socket wound healing in rats was better enhanced with 10% persica than 0.2% chlorhexidine.

  8. Implant decontamination with 2% chlorhexidine during surgical peri-implantitis treatment : a randomized, double-blind, controlled trial

    NARCIS (Netherlands)

    de Waal, Y. C. M.; Raghoebar, G. M.; Meijer, H. J. A.; Winkel, E. G.; van Winkelhoff, A. J.

    ObjectiveThe objective of this randomized, double-blind, controlled trial was to evaluate the clinical, radiographic, and microbiological effects of implant surface decontamination with a 2% chlorhexidine (CHX) solution in comparison with a 0.12% chlorhexidine+0.05% cetylpyridinium chloride (CPC)

  9. Current state of a dual behaviour of antimicrobial peptides-Therapeutic agents and promising delivery vectors.

    Science.gov (United States)

    Piotrowska, Urszula; Sobczak, Marcin; Oledzka, Ewa

    2017-12-01

    Micro-organism resistance is an important challenge in modern medicine due to the global uncontrolled use of antibiotics. Natural and synthetic antimicrobial peptides (AMPs) symbolize a new family of antibiotics, which have stimulated research and clinical interest as new therapeutic options for infections. They represent one of the most promising antimicrobial substances, due to their broad spectrum of biological activity, against bacteria, fungi, protozoa, viruses, yeast and even tumour cells. Besides, being antimicrobial, AMPs have been shown to bind and neutralize bacterial endotoxins, as well as possess immunomodulatory, anti-inflammatory, wound-healing, angiogenic and antitumour properties. In contrast to conventional antibiotics, which have very defined and specific molecular targets, host cationic peptides show varying, complex and very rapid mechanisms of actions that make it difficult to form an effective antimicrobial defence. Importantly, AMPs display their antimicrobial activity at micromolar concentrations or less. To do this, many peptide-based drugs are commercially available for the treatment of numerous diseases, such as hepatitis C, myeloma, skin infections and diabetes. Herein, we present an overview of the general mechanism of AMPs action, along with recent developments regarding carriers of AMPs and their potential applications in medical fields. © 2017 John Wiley & Sons A/S.

  10. SCREENING OF ANTIMICROBIAL ACTIVITY AND GENES CODING POLYKETIDE SYNTHETASE AND NONRIBOSOMAL PEPTIDE SYNTHETASE OF ACTINOMYCETE ISOLATES

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    Silvia Kovácsová

    2013-12-01

    Full Text Available The aim of this study was to observe antimicrobial activity using agar plate diffusion method and screening genes coding polyketide synthetase (PKS-I and nonribosomal peptide synthetase (NRPS from actinomycetes. A total of 105 actinomycete strains were isolated from arable soil. Antimicrobial activity was demonstrated at 54 strains against at least 1 of total 12 indicator organisms. Antifungal properties were recorded more often than antibacterial properties. The presence of PKS-I and NRPS genes were founded at 61 of total 105 strains. The number of strains with mentioned biosynthetic enzyme gene fragments matching the anticipated length were 19 (18% and 50 (47% respectively. Overall, five actinomycete strains carried all the biosynthetical genes, yet no antimicrobial activity was found against any of tested pathogens. On the other hand, twenty-one strains showed antimicrobial activity even though we were not able to amplify any of the PKS or NRPS genes from them. Combination of the two methods showed broad-spectrum antimicrobial activity of actinomycetes isolated from arable soil, which indicate that actinomycetes are valuable reservoirs of novel bioactive compounds.

  11. Adaptation of a hospital electronic referral system for antimicrobial stewardship prospective audit and feedback rounds.

    Science.gov (United States)

    Rawlins, Matthew D M; Raby, Edward; Sanfilippo, Frank M; Douglass, Rae; Chambers, Jonathan; McLellan, Duncan; Dyer, John R

    2018-05-04

    To evaluate the impact of the adaptation of an existing electronic referral application for use in antimicrobial stewardship prospective audit and feedback rounds (antimicrobial rounds). Retrospective, single-centre observational study between March 2015 and February 2016. A new quaternary referral centre. Adults referred for antimicrobial rounds outside of the intensive care and haematology units. Adaptation of an electronic referral application used by medical and allied health staff. A questionnaire-style referral form was designed to capture patient clinical details using a combination of free text and dropdown menus. Clinical pharmacists were educated and granted access to the system. The proportion of completed electronic referrals of total round reviews by month for the 12 months after implementation. The time from request to completion of reviews. The impact on adherence to advice provided on rounds. The impact on the institutional usage of broad-spectrum antibiotics: glycopeptides, carbapenems, third and fourth generation cephalosporins, fluoroquinolones and piperacillin/tazobactam. Over the study period, the proportion of electronic referrals of completed antimicrobial round reviews increased from 59% to 88% (P < 0.001); 75.7% of accepted electronic referrals were seen within 48 h of request. The proportion of advice ignored fell from 18% to 8.5% (P < 0.001). Piperacillin/tazobactam, fluoroquinolone and glycopeptide usage decreased. The adaptation of an electronic referral application for antimicrobial rounds was associated with increased adherence to advice and reduction in use in target antibiotics. Our model is now used at other institutions.

  12. Animation of Antimicrobial Resistance

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    Full Text Available ... Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing options ... CVM) produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, ...

  13. Animation of Antimicrobial Resistance

    Medline Plus

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

  14. Animation of Antimicrobial Resistance

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    Full Text Available ... Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing options ... produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, ...

  15. Animation of Antimicrobial Resistance

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    Full Text Available ... Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin it More sharing ... CVM) produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over ...

  16. Efficacy of Chlorhexidine, Xylitol, and Chlorhexidine + Xylitol against Dental Plaque, Gingivitis, and Salivary Streptococcus mutans Load: A Randomised Controlled Trial.

    Science.gov (United States)

    Marya, Charu Mohan; Taneja, Pratibha; Nagpal, Ruchi; Marya, Vandana; Oberoi, Sukhvinder Singh; Arora, Dimple

    To compare the antiplaque, antigingivitis and antibacterial efficacy of chlorhexidine (CHX), XYL and a mouthwash combining CHX and XYL against Streptococcus mutans (S. mutans). A parallel design, randomised controlled trial was conducted among 75 dental students. Participants were randomised into CHX, CHX+XYL and XYL-only groups using the lottery method. Subjects were instructed to use 10 ml of the provided mouthwash for 15 s twice daily for 3 weeks. All the outcome measures, gingival index (GI), plaque index (PI) and number of salivary S. mutans CFU were recorded at baseline and 3 weeks post intervention. Nonparametric tests were used for inferential statistics. All outcome variables (GI, PI scores and log10 salivary S. mutans counts) decreased significantly from baseline compared to post intervention among all three groups. Intergroup comparison demonstrated that reduction in GI was not significantly different among the three groups. The decrease in PI scores was found to be significantly higher in the XYL group, while the decrease in the log10 salivary S. mutans count was significantly higher in the CHX+XYL group. The present study provided sufficient data to suggest that all the three mouthwashes are effective against plaque, gingivitis and S. mutans load in saliva. Further investigations should be carried out to confirm the results and develop strategies for using such products to prevent tooth decay.

  17. Animation of Antimicrobial Resistance

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    ... Animal & Veterinary Cosmetics Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin ...

  18. Animation of Antimicrobial Resistance

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    Full Text Available ... Animal & Veterinary Cosmetics Tobacco Products Animal & Veterinary Home Animal & Veterinary Safety & Health Antimicrobial Resistance Animation of Antimicrobial Resistance Share Tweet Linkedin Pin ...

  19. Animation of Antimicrobial Resistance

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    Full Text Available ... More in Antimicrobial Resistance National Antimicrobial Resistance Monitoring System ... If you need help accessing information in different file formats, see Instructions for Downloading ...

  20. Comparison of Antibacterial Effect of Fluoride and Chlorhexidine on Two Cariogenic Bacteria: An in Vitro Study

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    Poureslami HR

    2014-09-01

    Full Text Available Statement of problem: Dental plaque is the main source for dental caries and there is no proper vaccine that can affect dental plaques. Objectives: Daily use of an efficient anti-plaque product can be very beneficial in plaque control and, thus, prevention of caries. This study aims to evaluate the antibacterial effects of four products of Chlorhexidine and Fluoride on two types of cariogenic bacteria. Materials and Methods: In this in vitro study, the antibacterial effect of Chlorhexidine and Fluoride (gel and solution against Streptococci Sanguis and Sobrinus was evaluated. Chlorhexidine gluconate 1% gel (Corosodyl, France, Chlorhexidine gluconate 2% solution (Consepsis, Ultradent, US, Sodium fluoride 0.2% solution (Oral-B, US and Acidulated Phosphate Fluoride 1.23% gel ( Denti-Care, Canada were used. The disc diffusion method was used for testing bacterial sensitivity. The data were analyzed using paired t-test and Chi-square test. Results: In comparison with the negative control, each of the four gels and solutions showed antibacterial effects but the effects were not statistically significant for fluoride solution (P=0.217. For S. Sobrinus, the mean diameter of inhibition zone around the discs coated with fluoride gel (F g, fluoride solution (F s, Chlorhexidine gel (CHX g and Chlorhexidine solution (CHX s were 19, 9, 21.5 and 27.5mm, respectively. For S. Sanguis, the mean diameter of inhibition zone around the discs coated with F g, F s, CHX g and CHX s were 17, 11, 17 and 25mm, respectively. CHX s had the most effect on both bacteria and F s had the least. CHX g and F g were less effective than CHX s, respectively. Conclusion: The results demonstrated that 2% CHX s and 1.23% F g can be effective on inhibition of the growth of some of cariogenic bacteria. Therefore, these agents can be used in the prevention of Early Childhood Caries.

  1. Effect of chlorhexidine on oral airway biofilm formation of Staphylococcus epidermidis

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    Ünase Büyükkoçak

    2015-12-01

    Full Text Available Objective: Biofilm formation of microorganisms on the surface of airways may lead to supraglottic colonization that may cause lower respiratuar tract infections. Studies searching the efficiency of local disinfectants on biofilm formation are limited. The aim of this study was to investigate the effects of chlorhexidine coated airways on biofilm formation of Staphylococcus epidermidis. Methods: Culture and electron microscopy methods were used for biofilm assessment. Airways were divided into two groups to investigate the effects of chlorhexidine on number of bacteria attached to the airway and biofilm formation. Group 1(control: naive material, S. epidermidis, Group 2: chlorhexidine coated material, S. epidermidis. No process was applied in Group 1. Chlorhexidine gluconate (0.2% was sprayed on the surface of naive material for four seconds and then left to dry in air, in Group to. Number of bacteria attached to the airway were counted by microbiological methods and biofilm formation was shown by Scanning Electron Microscope (SEM. Mann-Whitney u test was performed for statistical analyses. Results: In Group 2, bacteria numbers were 1x102-8x102 cfu/ml, whereas they were 3x103-1x104 cfu/ml in Group 1. Chlorhexidine decreased number of microorganisms attached to the airways with statistical significance (p=0.04. The results of the electron microscopic evaluation were in accordance with the acteriological findings. Conclusion: This study has shown that chlorhexidine coating can successfully reduce the number of adhered bacteria and biofilm formation on airways. J Microbiol Infect Dis 2015;5(4: 162-166

  2. Antimicrobial activity of different filling pastes for deciduous tooth treatment

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    Bruna Feltrin ANTONIAZZI

    2015-01-01

    Full Text Available Guedes-Pinto paste is the filling material most employed in Brazil for endodontic treatment of deciduous teeth; however, the Rifocort® ointment has been removed. Thus, the aim of this study was to investigate the antimicrobial potential of filling pastes, by proposing three new pharmacological associations to replace Rifocort® ointment with drugs of already established antimicrobial power: Nebacetin® ointment, 2% Chlorhexidine Gluconate gel, and Maxitrol® ointment. A paste composed of Iodoform, Rifocort® ointment and Camphorated Paramonochlorophenol (CPC was employed as the gold standard (G1. The other associations were: Iodoform, Nebacetin® ointment and CPC (G2; Iodoform, 2% Chlorhexidine Digluconate gel and CPC (G3; Iodoform, Maxitrol® ointment and CPC (G4. The associations were tested for Staphylococcus aureus (S. aureus, Streptococcus mutans (S. mutans, Streptococcus oralis (S. oralis, Enterococcus faecalis (E. faecalis, Escherichia coli (E. coli, and Bacillus subtilis (B. subtilis, using the methods of dilution on solid medium – orifice agar – and broth dilution. The results were tested using statistical analysis ANOVA and Kruskal-Wallis. They showed that all the pastes had a bacteriostatic effect on all the microorganisms, without any statistically significant difference, compared with G1. S. aureus was statistically significant (multiple comparison test of Tukey, insofar as G2 and G3 presented the worst and the best performance, respectively. All associations were bactericidal for E. coli, S. aureus, S. mutans and S. oralis. Only G3 and G4 were bactericidal for E. faecalis, whereas no product was bactericidal for B. subtilis. Thus, the tested pastes have antimicrobial potential and have proved acceptable for endodontic treatment of primary teeth.

  3. Antimicrobial potential of Casearia sylvestris against oral bacteria

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    Amanda Henriques CAVALHEIRO

    Full Text Available Abstract Aim The aim of this study was to obtain Casearia sylvestris leave extracts by different extractive methods, including the obtention of essential oil, in order to compare their antimicrobial activities to conventional mouthwash chlorhexidine against oral bacteria. Material and method For this evaluation, extracts from the leaves were obtained by different methods of extraction (infusion, decoction, maceration and percolation using different solvent systems: water 100%, ethanol 100%, methanol 100%, water: ethanol 3:7; water: ethanol 7:3; water: methanol 7:3 and water: methanol 3:7. The essential oil, which corresponds to a volatile fraction, was obtained by hydrodistillation using Clevenger modified apparatus. The microdilution broth method was used to determine the values of minimum inhibitory concentration (MIC and minimum bactericidal concentration (MBC for the following microorganisms: Streptococcus mutans ATCC 25175, S. mitis ATCC 49456, S. sanguinis ATCC 10556, S. salivarius ATCC 25975, Lactobacillus casei ATCC 11578 and Enterococcus faecalis ATCC4082. Chlorhexidine gluconate was used as a positive control. Result All extracts evaluated in the used protocol displayed MIC values higher than 400 µg/mL and few showed bactericidal activity. The antimicrobial activity of essential oil was higher than the activity of the extracts, and the best minimum inhibitory concentration and minimum bactericidal concentration values were obtained against L. casei (MIC of 0.023 µg/mL and MBC of 0.046 µg/mL and S. mutans (MIC of 25 µg/mL and MBC of 50 µg/mL, respectively. Conclusion The essential oil of Casearia sylvestris has significant antimicrobial activity against oral microorganisms.

  4. Rhamnolipids and lactonic sophorolipids: natural antimicrobial surfactants for oral hygiene.

    Science.gov (United States)

    Elshikh, M; Moya-Ramírez, I; Moens, H; Roelants, S; Soetaert, W; Marchant, R; Banat, I M

    2017-11-01

    To assess the efficacy of rhamnolipid (mixture of monorhamnolipid and dirhamnolipid congeners), purified monorhamnolipid, dirhamnolipid and lactonic sophorolipid biosurfactants against pathogens important for oral hygiene. Acquired and produced biosurfactants were fully characterized to allow the antimicrobial activity to be assigned to the biosurfactant congeners. Antimicrobial activity was assessed using the resazurin-aided microdilution method. Mixed rhamnolipid JBR425 (MR) and lactonic sophorolipids (LSLs) demonstrated the lowest minimum inhibitory concentration (MIC) which ranged between 100 and 400 μg ml -1 against Streptococcus mutans, Streptococcus oralis, Actinomyces naeslundii, Neisseria mucosa and Streptococcus sanguinis. Combining these biosurfactants with standard antimicrobial agents namely chlorhexidine, sodium lauryl sulphate, tetracycline HCl and ciprofloxacin showed a dramatic drop in the MIC values. In addition, in vitro studies demonstrated the biosurfactants' ability to prevent and disrupt oral pathogens biofilms. The increased permeability of microorganisms treated with biosurfactant, as shown using bisbenzimide dye, in part explains the inhibition effect. The results demonstrate that rhamnolipids and LSLs have the ability to inhibit oral pathogens both in planktonic and oral biofilm states. The findings indicate the potential value of biosurfactants for both oral hygiene and the pharmaceutical industries since there is a serious need to reduce the reliance on synthetic antimicrobials and antibiotics. © 2017 The Society for Applied Microbiology.

  5. Transgenic Brassica juncea plants expressing MsrA1, a synthetic cationic antimicrobial peptide, exhibit resistance to fungal phytopathogens.

    Science.gov (United States)

    Rustagi, Anjana; Kumar, Deepak; Shekhar, Shashi; Yusuf, Mohd Aslam; Misra, Santosh; Sarin, Neera Bhalla

    2014-06-01

    Cationic antimicrobial peptides (CAPs) have shown potential against broad spectrum of phytopathogens. Synthetic versions with desirable properties have been modeled on these natural peptides. MsrA1 is a synthetic chimera of cecropin A and melittin CAPs with antimicrobial properties. We generated transgenic Brassica juncea plants expressing the msrA1 gene aimed at conferring fungal resistance. Five independent transgenic lines were evaluated for resistance to Alternaria brassicae and Sclerotinia sclerotiorum, two of the most devastating pathogens of B. juncea crops. In vitro assays showed inhibition by MsrA1 of Alternaria hyphae growth by 44-62 %. As assessed by the number and size of lesions and time taken for complete leaf necrosis, the Alternaria infection was delayed and restricted in the transgenic plants with the protection varying from 69 to 85 % in different transgenic lines. In case of S. sclerotiorum infection, the lesions were more severe and spread profusely in untransformed control compared with transgenic plants. The sclerotia formed in the stem of untransformed control plants were significantly more in number and larger in size than those present in the transgenic plants where disease protection of 56-71.5 % was obtained. We discuss the potential of engineering broad spectrum biotic stress tolerance by transgenic expression of CAPs in crop plants.

  6. Antimicrobial Drugs in Fighting against Antimicrobial Resistance

    OpenAIRE

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

    2016-01-01

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

  7. Interscience Conference on Antimicrobial Agents and Chemotherapy--49th annual meeting. Part 2. 12-15 September 2009, San Francisco, CA, USA.

    Science.gov (United States)

    Turner, Ben; Murch, Lisa

    2009-11-01

    The Interscience Conference on Antimicrobial Agents and Chemotherapy held in San Francisco included topics covering new therapeutic developments for the treatment of infectious diseases. This conference report highlights selected presentations on several antibiotics in development including a broad-spectrum penem beta-lactam antibiotic, a novel siderophore monobactam, as well as other novel antibiotics. Investigational drugs discussed include sulopenem and sulopenem etzadroxil (both Pfizer Inc), BAL-30072 (Basilea Pharmaceutica International Ltd), TP-120 and TP-787 (both Tetraphase Pharmaceuticals Inc), NAI-107 (New Anti Infectives Consortium/NexThera Biosciences) and ABI-200 (AdRem Biotech/US Department of Agriculture).

  8. Reduction of exit-site infections of tunnelled intravascular catheters among neutropenic patients by sustained-release chlorhexidine dressings: results from a prospective randomized controlled trial.

    Science.gov (United States)

    Chambers, S T; Sanders, J; Patton, W N; Ganly, P; Birch, M; Crump, J A; Spearing, R L

    2005-09-01

    Exit-site and tunnel infections of tunnelled central intravascular catheters are a frequent source of morbidity among neutropenic patients and may necessitate catheter removal. They require antimicrobial therapy that increases healthcare costs and is associated with adverse drug reactions. A prospective randomized clinical trial was conducted among adult patients undergoing chemotherapy in a haematology unit. Tunnelled intravascular catheters were randomized to receive the control of a standard dressing regimen as recommended by the British Committee for Standards in Haematology, or to receive the intervention of a sustained-release chlorhexidine dressing. Follow-up data were available in 112 of 114 tunnelled intravascular catheters which were randomized. Exit-site or combined exit-site/tunnel infections occurred in 23 (43%) of 54 catheters in the control group, and five (9%) of 58 catheters in the intervention group [odds ratio (OR) for intervention group compared with control group =0.13, 95% confidence intervals (CI) 0.04-0.37, P<0.001]. More tunnelled intravascular catheters were prematurely removed from the control group than the intervention group for documented infections [20/54 (37%) vs 6/58 (10%), OR=0.20, 95%CI 0.53-0.07]. However, there was no difference in the numbers of tunnelled intravascular catheters removed for all proven and suspected intravascular catheter-related infections [21/54 (39%) vs 19/58 (33%)], or in the time to removal of catheters for any reason other than death or end of treatment for underlying disease. Thus chlorhexidine dressings reduced the incidence of exit-site/tunnel infections of indwelling tunnelled intravascular catheters without prolonging catheter survival in neutropenic patients, and could be considered as part of the routine management of indwelling tunnelled intravascular catheters among neutropenic patients.

  9. Antimicrobial activity of disinfectant agents incorporated into type IV dental stone.

    Science.gov (United States)

    Pereira, Rodrigo de Paula; Lucas, Matheus Guilherme; Spolidorio, Denise Madalena Palomari; Arioli Filho, João Neudenir

    2012-06-01

    This study evaluated the antimicrobial activity of two disinfectant agents, 2% chlorhexidine digluconate solution (CHX) and 98% chlorhexidine hydrochloride powder (HYD), incorporated into type IV dental stone at the time of mixing. Agar diffusion test was used for the following microorganisms: Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Candida albicans. The specimens were grouped in: (1) dental stone mixed with sterile distilled water; (2) paper disc soaked with CHX; (3) dental stone mixed with CHX; and (4) dental stone with incorporation of HYD, in 1% proportion of the dental stone mass and mixed with sterile distilled water. The culture medium was inoculated with microbial suspensions 1 and 24 h after pouring of the dental stone. The antimicrobial activity was evaluated by the average diameter of microbial growth inhibition zones. The data were analysed with a nested anova (p < 0.05) and Tukey test for specific comparisons. The disinfectant agents demonstrated antimicrobial activity against all microorganisms, with the exception of C. albicans, against which the CHX was ineffective in two periods of analysis. Significant differences between disinfectants were found with all microorganisms. The disinfectant agents analysed were effective against most of the microorganisms tested, except C. albicans. © 2011 The Gerodontology Society and John Wiley & Sons A/S.

  10. Antioxidant and antimicrobial activities of Bauhinia racemosa L. stem bark

    Directory of Open Access Journals (Sweden)

    Kumar R.S.

    2005-01-01

    Full Text Available The present study was carried out to evaluate the antioxidant and antimicrobial activities of a methanol extract of Bauhinia racemosa (MEBR (Caesalpiniaceae stem bark in various systems. 1,1-Diphenyl-2-picryl-hydrazyl (DPPH radical, superoxide anion radical, nitric oxide radical, and hydroxyl radical scavenging assays were carried out to evaluate the antioxidant potential of the extract. The antioxidant activity of the methanol extract increased in a concentration-dependent manner. About 50, 100, 250, and 500 µg MEBR inhibited the peroxidation of a linoleic acid emulsion by 62.43, 67.21, 71.04, and 76.83%, respectively. Similarly, the effect of MEBR on reducing power increased in a concentration-dependent manner. In DPPH radical scavenging assays the IC50 value of the extract was 152.29 µg/ml. MEBR inhibited the nitric oxide radicals generated from sodium nitroprusside with an IC50 of 78.34 µg/ml, as opposed to 20.4 µg/ml for curcumin. Moreover, MEBR scavenged the superoxide generated by the PMS/NADH-NBT system. MEBR also inhibited the hydroxyl radical generated by Fenton's reaction, with an IC50 value of more than 1000 µg/ml, as compared to 5 µg/ml for catechin. The amounts of total phenolic compounds were also determined and 64.7 µg pyrocatechol phenol equivalents were detected in MEBR (1 mg. The antimicrobial activities of MEBR were determined by disc diffusion with five Gram-positive, four Gram-negative and four fungal species. MEBR showed broad-spectrum antimicrobial activity against all tested microorganisms. The results obtained in the present study indicate that MEBR can be a potential source of natural antioxidant and antimicrobial agents.

  11. Antioxidant and antimicrobial properties of traditional green and purple "Napoletano" basil cultivars (Ocimum basilicum L.) from Campania region (Italy).

    Science.gov (United States)

    Tenore, Gian Carlo; Campiglia, Pietro; Ciampaglia, Roberto; Izzo, Luana; Novellino, Ettore

    2017-09-01

    The present study is the first effort to a comprehensive evaluation of the antioxidant and antimicrobial activities of 'Napoletano' green and purple basil (Ocimum basilicum L.) varieties. The results obtained revealed that the basil sample extracts were characterised by a generally higher polyphenolic concentration than those reported elsewhere for other more conventional and geographically different basil varieties. Napoletano purple basil revealed higher radical-scavenging and ferric-reducing capacities than the green one probably due to its relevant anthocyanin content. As regards the antimicrobial properties, both basil varieties exhibited activity against a broad spectrum of food-borne and human pathogenic micro-organisms, revealing not only a moderate to high natural preserving capacity, but also potentially beneficial influence on human health. Results indicated Napoletano green and purple basils as a good source of antioxidants of potential nutraceutical interest.

  12. Design and synthesis of some new 2,3'-bipyridine-5-carbonitriles as potential anti-inflammatory/antimicrobial agents.

    Science.gov (United States)

    Elzahhar, Perihan A; Elkazaz, Salwa; Soliman, Raafat; El-Tombary, Alaa A; Shaltout, Hossam A; El-Ashmawy, Ibrahim M; Abdel Wahab, Abeer E; El-Hawash, Soad A

    2017-08-01

    Inflammation may cause accumulation of fluid in the injured area, which may promote bacterial growth. Other reports disclosed that non-steroidal anti-inflammatory drugs may enhance progression of bacterial infection. This work describes synthesis of new series of 2,3'-bipyridine-5-carbonitriles as structural analogs of etoricoxib, linked at position-6 to variously substituted thio or oxo moieties. Biological screening results revealed that compounds 2b, 4b, 7e and 8 showed significant acute and chronic AI activities and broad spectrum of antimicrobial activity. In addition, similarity ensemble approach was applied to predict potential biological targets of the tested compounds. Then, pharmacophore modeling study was employed to determine the most important structural parameters controlling bioactivity. Moreover, title compounds showed physicochemical properties within those considered adequate for drug candidates. This study explored the potential of such series of compounds as structural leads for further modification to develop a new class of dual AI-antimicrobial agents.

  13. An economic evaluation of a chlorhexidine chip for treating chronic periodontitis: the CHIP (chlorhexidine in periodontitis) study.

    Science.gov (United States)

    Henke, C J; Villa, K F; Aichelmann-Reidy, M E; Armitage, G C; Eber, R M; Genco, R J; Killoy, W J; Miller, D P; Page, R C; Polson, A M; Ryder, M I; Silva, S J; Somerman, M J; Van Dyke, T E; Wolff, L F; Evans, C J; Finkelman, R D

    2001-11-01

    The authors previously suggested that an adjunctive, controlled-release chlorhexidine, or CHX, chip may reduce periodontal surgical needs at little additional cost. This article presents an economic analysis of the CHX chip in general dental practice. In a one-year prospective clinical trial, 484 chronic periodontitis patients in 52 general practices across the United States were treated with either scaling and root planing, or SRP, plus any therapy prescribed by treating, unblinded dentists; or SRP plus other therapy as above but including the CHX chip. Economic data were collected from bills, case report forms and 12-month treatment recommendations from blinded periodontist evaluators. Total dental charges were higher for SRP + CHX chip patients vs. SRP patients when CHX chip costs were included (P = .027) but lower when CHX chip costs were excluded (P = .012). About one-half of the CHX chip acquisition cost was offset by savings in other charges. SRP + CHX chip patients were about 50 percent less likely to undergo surgical procedures than were SRP patients (P = .021). At the end of the trial, periodontist evaluators recommended similar additional procedures for both groups: SRP, about 46 percent; maintenance, about 37 percent; surgery, 56 percent for SRP alone and 63 percent for SRP + CHX chip. Adjunctive CHX chip use for general-practice patients with periodontitis increased costs but reduced surgeries over one year. At study's end, periodontists recommended similar additional surgical treatment for both groups. In general practice, routine use of the CHX chip suggests that costs will be partially offset by reduced surgery over at least one year.

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

    Directory of Open Access Journals (Sweden)

    Juraithip Wungsintaweekul

    2010-12-01

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

  15. Interaction of MreB-derived antimicrobial peptides with membranes.

    Science.gov (United States)

    Saikia, Karabi; Chaudhary, Nitin

    2018-03-25

    Antimicrobial peptides are critical components of defense systems in living forms. The activity is conferred largely by the selective membrane-permeabilizing ability. In our earlier work, we derived potent antimicrobial peptides from the 9-residue long, N-terminal amphipathic helix of E. coli MreB protein. The peptides display broad-spectrum activity, killing not only Gram-positive and Gram-negative bacteria but opportunistic fungus, Candida albicans as well. These results proved that membrane-binding stretches of bacterial proteins could turn out to be self-harming when applied from outside. Here, we studied the membrane-binding and membrane-perturbing potential of these peptides. Steady-state tryptophan fluorescence studies with tryptophan extended peptides, WMreB 1-9 and its N-terminal acetylated analog, Ac-WMreB 1-9 show preferential binding to negatively-charged liposomes. Both the peptides cause permeabilization of E. coli inner and outer-membranes. Tryptophan-lacking peptides, though permeabilize the outer-membrane efficiently, little permeabilization of the inner-membrane is observed. These data attest membrane-destabilization as the mechanism of rapid bacterial killing. This study is expected to motivate the research in identifying microbes' self-sequences to combat them. Copyright © 2018 Elsevier Inc. All rights reserved.

  16. Insect antimicrobial peptides act synergistically to inhibit a trypanosome parasite.

    Science.gov (United States)

    Marxer, Monika; Vollenweider, Vera; Schmid-Hempel, Paul

    2016-05-26

    The innate immune system provides protection from infection by producing essential effector molecules, such as antimicrobial peptides (AMPs) that possess broad-spectrum activity. This is also the case for bumblebees, Bombus terrestris, when infected by the trypanosome, Crithidia bombi Furthermore, the expressed mixture of AMPs varies with host genetic background and infecting parasite strain (genotype). Here, we used the fact that clones of C. bombi can be cultivated and kept as strains in medium to test the effect of various combinations of AMPs on the growth rate of the parasite. In particular, we used pairwise combinations and a range of physiological concentrations of three AMPs, namely Abaecin, Defensin and Hymenoptaecin, synthetized from the respective genomic sequences. We found that these AMPs indeed suppress the growth of eight different strains of C. bombi, and that combinations of AMPs were typically more effective than the use of a single AMP alone. Furthermore, the most effective combinations were rarely those consisting of maximum concentrations. In addition, the AMP combination treatments revealed parasite strain specificity, such that strains varied in their sensitivity towards the same mixtures. Hence, variable expression of AMPs could be an alternative strategy to combat highly variable infections.This article is part of the themed issue 'Evolutionary ecology of arthropod antimicrobial peptides'. © 2016 The Author(s).

  17. Antimicrobial peptides from the skins of North American frogs.

    Science.gov (United States)

    Conlon, J Michael; Kolodziejek, Jolanta; Nowotny, Norbert

    2009-08-01

    North America is home to anuran species belonging to the families Bufonidae, Eleutherodactylidae, Hylidae, Leiopelmatidae, Ranidae, and Scaphiopodidae but antimicrobial peptides have been identified only in skin secretions and/or skin extracts of frogs belonging to the Leiopelmatidae ("tailed frogs") and Ranidae ("true frogs"). Eight structurally-related cationic alpha-helical peptides with broad-spectrum antibacterial activity, termed ascaphins, have been isolated from specimens of Ascaphus truei (Leiopelmatidae) occupying a coastal range. Characterization of orthologous antimicrobial peptides from Ascaphus specimens occupying an inland range supports the proposal that this population should be regarded as a separate species A. montanus. Ascaphin-8 shows potential for development into a therapeutically valuable anti-infective agent. Peptides belonging to the brevinin-1, esculentin-1, esculentin-2, palustrin-1, palustrin-2, ranacyclin, ranatuerin-1, ranatuerin-2, and temporin families have been isolated from North American ranids. It is proposed that "ranalexins" represent brevinin-1 peptides that have undergone a four amino acid residue internal deletion. Current taxonomic recommendations divide North American frogs from the family Ranidae into two genera: Lithobates and Rana. Cladistic analysis based upon the amino acid sequences of the brevinin-1 peptides provides strong support for this assignment.

  18. The forgotten role of alcohol: a systematic review and meta-analysis of the clinical efficacy and perceived role of chlorhexidine in skin antisepsis.

    Directory of Open Access Journals (Sweden)

    Matthias Maiwald

    Full Text Available BACKGROUND: Skin antisepsis is a simple and effective measure to prevent infections. The efficacy of chlorhexidine is actively discussed in the literature on skin antisepsis. However, study outcomes due to chlorhexidine-alcohol combinations are often attributed to chlorhexidine alone. Thus, we sought to review the efficacy of chlorhexidine for skin antisepsis and the extent of a possible misinterpretation of evidence. METHODS: We performed a systematic literature review of clinical trials and systematic reviews investigating chlorhexidine compounds for blood culture collection, vascular catheter insertion and surgical skin preparation. We searched PubMed, CINAHL, the Cochrane Library, the Agency for Healthcare Research and Quality website, several clinical trials registries and a manufacturer website. We extracted data on study design, antiseptic composition, and the following outcomes: blood culture contamination, catheter colonisation, catheter-related bloodstream infection and surgical site infection. We conducted meta-analyses of the clinical efficacy of chlorhexidine compounds and reviewed the appropriateness of the authors' attribution. RESULTS: In all three application areas and for all outcomes, we found good evidence favouring chlorhexidine-alcohol over aqueous competitors, but not over competitors combined with alcohols. For blood cultures and surgery, we found no evidence supporting chlorhexidine alone. For catheters, we found evidence in support of chlorhexidine alone for preventing catheter colonisation, but not for preventing bloodstream infection. A range of 29 to 43% of articles attributed outcomes solely to chlorhexidine when the combination with alcohol was in fact used. Articles with ambiguous attribution were common (8-35%. Unsubstantiated recommendations for chlorhexidine alone instead of chlorhexidine-alcohol were identified in several practice recommendations and evidence-based guidelines. CONCLUSIONS: Perceived efficacy

  19. The forgotten role of alcohol: a systematic review and meta-analysis of the clinical efficacy and perceived role of chlorhexidine in skin antisepsis.

    Science.gov (United States)

    Maiwald, Matthias; Chan, Edwin S Y

    2012-01-01

    Skin antisepsis is a simple and effective measure to prevent infections. The efficacy of chlorhexidine is actively discussed in the literature on skin antisepsis. However, study outcomes due to chlorhexidine-alcohol combinations are often attributed to chlorhexidine alone. Thus, we sought to review the efficacy of chlorhexidine for skin antisepsis and the extent of a possible misinterpretation of evidence. We performed a systematic literature review of clinical trials and systematic reviews investigating chlorhexidine compounds for blood culture collection, vascular catheter insertion and surgical skin preparation. We searched PubMed, CINAHL, the Cochrane Library, the Agency for Healthcare Research and Quality website, several clinical trials registries and a manufacturer website. We extracted data on study design, antiseptic composition, and the following outcomes: blood culture contamination, catheter colonisation, catheter-related bloodstream infection and surgical site infection. We conducted meta-analyses of the clinical efficacy of chlorhexidine compounds and reviewed the appropriateness of the authors' attribution. In all three application areas and for all outcomes, we found good evidence favouring chlorhexidine-alcohol over aqueous competitors, but not over competitors combined with alcohols. For blood cultures and surgery, we found no evidence supporting chlorhexidine alone. For catheters, we found evidence in support of chlorhexidine alone for preventing catheter colonisation, but not for preventing bloodstream infection. A range of 29 to 43% of articles attributed outcomes solely to chlorhexidine when the combination with alcohol was in fact used. Articles with ambiguous attribution were common (8-35%). Unsubstantiated recommendations for chlorhexidine alone instead of chlorhexidine-alcohol were identified in several practice recommendations and evidence-based guidelines. Perceived efficacy of chlorhexidine is often in fact based on evidence for the

  20. Effect of chlorhexidine on the shear bond strength of self-etch ...

    African Journals Online (AJOL)

    The aim of this study was to investigate the effect of chlorhexidine on shear bond strength of self-etch adhesives to dentin. The crowns of 60 sound human premolars were horizontally sectioned to expose the coronal dentin. Dentin surfaces were polished with 320 grit silicon carbide papers, and were randomly divided into 4 ...

  1. Effect of a chlorhexidine-containing brush-on gel on peri-implant mucositis

    DEFF Research Database (Denmark)

    Hallström, H; Lindgren, S; Twetman, S

    2017-01-01

    ) and pocket probing depth (PPD). RESULTS: The groups were balanced at baseline. The daily use of the chlorhexidine-containing gel resulted in reduced BOP after 4 and 12 weeks compared with the control group (P PPD was significantly reduced (P

  2. Investigations on the uptake of 14C-labelled chlorhexidine diglutonate through dental enamel

    International Nuclear Information System (INIS)

    Stary, W.

    1981-01-01

    In this dissertation it was shown using radioactively labelled 14 C tracer molecules that chlorhexidine is adsorbed on the dental surface of extracted teeth. Evidence for this was provided by the three following methods: a) back diffusion and release in rinses; b) thin layer chromatography of the adsorbed substance, and c) autoradiography. (orig./MG) [de

  3. Intrinsic Klebsiella pneumoniae contamination of liquid germicidal hand soap containing chlorhexidine.

    Science.gov (United States)

    Brooks, Steven E; Walczak, Mary A; Malcolm, Sharon; Hameed, Rizwanullah

    2004-10-01

    We describe intrinsic contamination with Klebsiella pneumoniae occurring during the manufacture of germicidal hand soap, labeled as containing 2% chlorhexidine, used throughout a 350-bed community medical center. A 3-year retrospective study failed to find evidence of increased incidence of clinical isolates of this strain.

  4. In vitro susceptibility of gram-negative bacterial isolates to chlorhexidine gluconate.

    Science.gov (United States)

    Mengistu, Y; Erge, W; Bellete, B

    1999-05-01

    To investigate the susceptibility of clinical isolates of gram-negative bacteria to chlorhexidine gluconate. Prospective laboratory study. Tikur Anbessa Hospital, Addis Ababa, Ethiopia. Clinical specimens from 443 hospital patients. Significant number of gram negative bacteria were not inhibited by chlorhexidine gluconate (0.02-0.05%) used for antisepsis. Four hundred and forty three strains of gram-negative bacteria were isolated from Tikur Anbessa Hospital patients. Escherichia coli (31.6%) and Klebsiella pneumoniae (23%) were the most frequently isolated bacteria followed by Proteus species (13.3%), Pseudomonas species (9.2%), and Citrobacter species (6.1%). Each organism was tested to chlorhexidine gluconate (CHG), minimum inhibitory concentration (MIC) ranging from 0.0001% to 1%w/v. All Salmonella species and E. coli were inhibited by CHG, MIC or = 0.1%). Our results showed that a significant number of the gram-negative bacterial isolates were not inhibited by CHG at the concentration used for disinfection of wounds or instruments (MIC 0.02-0.05% w/v). It is therefore important to select appropriate concentration of this disinfectant and rationally use it for disinfection and hospital hygiene. Continuing follow up and surveillance is also needed to detect resistant bacteria to chlorhexidine or other disinfectants in time.

  5. EFFECT OF A COMBINED CHLORHEXIDINE AND NAF MOUTHRINSE - AN IN-VIVO HUMAN CARIES MODEL STUDY

    NARCIS (Netherlands)

    ULLSFOSS, BN; OGAARD, B; ARENDS, J; RUBEN, J; ROLLA, G; AFSETH, J

    Chlorhexidine (CHX) is probably the most widely used and the most potent chemical plaque inhibitory agent, whereas fluoride (F-) is the only truly accepted anticaries agent available at present. As they have discrete mechanisms of action, a combination effect of these agents on human dental caries

  6. Chlorine dioxide and chlorhexidine mouthrinses compared in a 3-day plaque accumulation model

    NARCIS (Netherlands)

    Paraskevas, S.; Rosema, N.A.M.; Versteeg, P.; van der Velden, U.; van der Weijden, G.A.

    2008-01-01

    Background: The aim of this study was to investigate the inhibiting effect of a chlorine dioxide mouthrinse as opposed to a mouthrinse containing chlorhexidine (0.20%) during 3 days of plaque accumulation. Methods: At baseline, all participants (N = 77) received a professional prophylaxis and were

  7. In vitro influence of 2% chlorhexidine on links established at the ...

    African Journals Online (AJOL)

    Sound dentin surfaces were exposed by operating low speed diamond disc at conventional speed with copious water spraying. ... applying adhesive, while teeth from the test group followed an intermediate stage of the application for 60 s of 2% chlorhexidine solution before applying adhesive system (Prime and Bond NT).

  8. Effects of different chlorhexidine pretreatments on adhesion of metal brackets in vitro

    Directory of Open Access Journals (Sweden)

    Frey Corinne

    2012-12-01

    Full Text Available Abstract Objective To investigate the effect of chlorhexidine applications in various forms and concentrations on adhesion and failure modes of metal brackets in vitro. Material and methods Ninety bovine enamel specimens were allocated to six groups (n=15. Metal brackets were bonded on all specimens after chlorhexidine pre-treatments forming the following groups: (1 untreated specimens (control; (2 40% varnish (EC40, Biodent BV, Netherlands, remnants removed with brushing mimicking patient cleaning; (3 40% varnish (EC40, remnants removed with brushing mimicking professional cleaning; (4 1% varnish (Cervitec Plus, Ivoclar vivadent, Schaan, Liechtenstein, remnants not removed; (5 brushed with% 1 gel (Corsodyl, GlaxoSmithKline, Münchenbuchsee, Germany, remnants not removed; (6 immersed in 0.07% mouthrinse (Corsodyl, GlaxoSmithKline, Münchenbuchsee, Germany, remnant not rinsed. Debonding of brackets was performed using a universal testing machine. Data were analysed using one-way ANOVA and post-hoc Scheffé test. Results Group 4 performed significantly inferior than all the other groups and the control. Group 4 presented the highest number of adhesive failures at the enamel-resin interface whereas in other groups no failures at adhesive-resin interface was observed. Conclusion Presence of chlorhexidine varnish prior to bracket bonding adversely affects adhesion. Concentration of chlorhexidine pre-treatment has no influence on shear bond strength.

  9. Effects of chlorhexidine varnish on caries during orthodontic treatment: a systematic review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Elaine Machado Pingueiro OKADA

    Full Text Available Abstract This study aimed to perform a systematic review and meta-analysis to evaluate the effectiveness of chlorhexidine varnish on the reduction of caries incidence during fixed orthodontic treatment. The literature searches involved The Cochrane Library, Medline, Scopus, OpenSigle databases and manual searches. The search on OpenSigle did not produce any additional articles. Clinical studies conducted in patients with orthodontic fixed appliances that used professional application of chlorhexidine varnish were included. The effect-size was calculated and a meta-analysis was performed. From 182 abstracts, a total of six articles fulfilled the inclusion criteria. After reading the full articles, one was excluded because of lack of a control group. Three articles were used for continuous data analysis, and two articles were used for the dichotomous data analysis. The pooled meta-analysis with continuous data demonstrated chlorhexidine varnish effectiveness on caries reduction (p = 0.003, with a mean difference and confidence interval of −1.49 [−2.47, −0.51]. On the basis of the pooled meta-analysis of continuous data, we were able to conclude that professional application of chlorhexidine varnish is effective in caries incidence reduction during fixed orthodontic treatment.

  10. Willingness to pay for a 4% chlorhexidine (7.1% chlorhexidine digluconate) product for umbilical cord care in rural Bangladesh: a contingency valuation study.

    Science.gov (United States)

    Coffey, Patricia S; Metzler, Mutsumi; Islam, Ziaul; Koehlmoos, Tracey P

    2013-10-18

    Recent trials in Bangladesh, Nepal, and Pakistan have shown that chlorhexidine is an effective antiseptic for umbilical cord care compared to existing community-based cord care practices. Because of the aggregate reduction in neonatal mortality in these trials, interest is high in introducing a 7.1% chlorhexidine digluconate liquid or gel that delivers 4% chlorhexidine for umbilical cord care in Bangladesh and elsewhere. In 2010, we conducted a household survey applying a contingent valuation method with 1717 eligible couples (pregnant women or women with a first child younger than 6 months old, and their husbands) in the rural subdistricts of Abhoynagar and Mirsarai in Bangladesh to assess their willingness to pay for three types of umbilical cord care products at different price points. Each respondent was asked about willingness to pay prefixed prices for any one of three 7.1% chlorhexidine digluconate products: 1) a single-dose liquid, 2) a multi-dose liquid, or 3) a gel formulation. Each also reported the maximum price they were independently willing to pay for their selected product. We compared participant willingness-to-pay responses to the prefixed prices with their independently reported maximum prices for each type of the product separately. The comparison identified to what extent the respondents' positive responses to the prefixed prices matched their independently reported maximum prices. This cross matching revealed that willingness to pay the prefixed prices was 41% for the single-dose liquid, 33% for the multi-dose liquid, and 31% for the gel formulation. Although the majority of the respondents were unwilling to pay the prefixed prices, all were willing to pay some amount and reported they could borrow money if necessary. Subsequent analysis of responses to the multi-dose liquid showed borrowing money would not be required if the unit price was Bangladeshi taka 15-25. A unit price of Bangladeshi taka 15-25 (US$0.21-0.35) for multi-dose 7

  11. A heterodimer comprised of two bovine lactoferrin antimicrobial peptides exhibits powerful bactericidal activity against Burkholderia pseudomallei.

    Science.gov (United States)

    Puknun, Aekkalak; Bolscher, Jan G M; Nazmi, Kamran; Veerman, Enno C I; Tungpradabkul, Sumalee; Wongratanacheewin, Surasakdi; Kanthawong, Sakawrat; Taweechaisupapong, Suwimol

    2013-07-01

    Melioidosis is a severe infectious disease that is endemic in Southeast Asia and Northern Australia. Burkholderia pseudomallei, the causative agent of this disease, has developed resistance to an increasing list of antibiotics, demanding a search for novel agents. Lactoferricin and lactoferrampin are two antimicrobial domains of lactoferrin with a broad spectrum of antimicrobial activity. A hybrid peptide (LFchimera) containing lactoferrampin (LFampin265-284) and a part of lactoferricin (LFcin17-30) has strikingly higher antimicrobial activities compared to the individual peptides. In this study, the antimicrobial activities of this chimeric construct (LFchimera1), as well as of another one containing LFcin17-30 and LFampin268-284, a shorter fragment of LFampin265-284 (LFchimera2), and the constituent peptides were tested against 7 isolates of B. pseudomallei and compared to the preferential antibiotic ceftazidime (CAZ). All isolates including B. pseudomallei 979b shown to be resistant to CAZ, at a density of 10(5) CFU/ml, could be killed by 5-10 μM of LFchimera1 within 2 h, while the other peptides as well as the antibiotic CAZ only inhibited the B. pseudomallei strains resulting in an overgrowth in 24 h. These data indicate that LFchimera1 could be considered for development of therapeutic agents against B. pseudomallei.

  12. Identification of didecyldimethylammonium salts and salicylic acid as antimicrobial compounds in commercial fermented radish kimchi.

    Science.gov (United States)

    Li, Jing; Chaytor, Jennifer L; Findlay, Brandon; McMullen, Lynn M; Smith, David C; Vederas, John C

    2015-03-25

    Daikon radish (Raphanus sativus) fermented with lactic acid bacteria, especially Leuconostoc or Lactobacillus spp., can be used to make kimchi, a traditional Korean fermented vegetable. Commercial Leuconostoc/radish root ferment filtrates are claimed to have broad spectrum antimicrobial activity. Leuconostoc kimchii fermentation products are patented as preservatives for cosmetics, and certain strains of this organism are reported to produce antimicrobial peptides (bacteriocins). We examined the antimicrobial agents in commercial Leuconostoc/radish root ferment filtrates. Both activity-guided fractionation with Amberlite XAD-16 and direct extraction with ethyl acetate gave salicylic acid as the primary agent with activity against Gram-negative bacteria. Further analysis of the ethyl acetate extract revealed that a didecyldimethylammonium salt was responsible for the Gram-positive activity. The structures of these compounds were confirmed by a combination of (1)H- and (13)C NMR, high-performance liquid chromatography, high-resolution mass spectrometry, and tandem mass spectrometry analyses. Radiocarbon dating indicates that neither compound is a fermentation product. No antimicrobial peptides were detected.

  13. Non-observance of guidelines for surgical antimicrobial prophylaxis and surgical-site infections.

    Science.gov (United States)

    Lallemand, S; Thouverez, M; Bailly, P; Bertrand, X; Talon, D

    2002-06-01

    A prospective multicentre study was conducted to assess major aspects of surgical prophylaxis and to determine whether inappropriate antimicrobial prophylaxis was a factor associated (risk or protective factor) with surgical site infection (SSI). Surgical prophylaxis practices were assessed by analysing four variables: indication, antimicrobial agent, timing and duration. Univariate and multivariate analyses were carried out to identify predictors of SSI among patient-specific, operation-specific and antimicrobial prophylaxis-specific factors. The frequency of SSI was 2.7% (13 SSI in 474 observations). Total compliance of the prescription with guidelines was observed in 41.1% of cases (195 prescriptions). Of the 139 patients who received an inappropriate drug, 126 (90.6%) received a drug with a broader spectrum than the recommended drug. Prophylaxis was prolonged in 71 (87.7%) of the 81 patients who received prophylaxis for inappropriate lengths of time and 43 (61.4%) of the 70 patients who did not receive prophylaxis at the optimal moment were treated too late. Multivariate analysis clearly demonstrated that SSI was associated with multiple procedures (relative risk 8.5), short duration of prophylaxis (relative risk 12.7) and long-term therapy with antimicrobial agents during the previous year (relative risk 8.8). The ecological risk of the emergence of resistance associated with the frequent use of broad-spectrum antibiotics and prophylaxis for longer periods was not offset by individual benefit to the patients who received inappropriate prophylaxis.

  14. Antibacterial efficacy of lavandula officinalis extract, sodium hypochlorite and chlorhexidine gluconate solutions as root canal irrigations: A comparative analysis

    Directory of Open Access Journals (Sweden)

    pouya Mehmandoust

    2016-03-01

    Full Text Available Introduction: This in vitro study aimed to compare the antimicrobial effect of lavandula -0fficinalis extract, with sodium hypochlorite (NaOCL and chlorhexidine gluconate (CHX, as root canal irrigants, on Enterococcus faecalis (EF. Materials &Methods: Seventy five extracted single-rooted premolars were selected. Root canals were prepared using rotary ProTaper system and were infected with the culture of E. faecalis. Specimens were randomly divided into five groups (n = 15, Group 1, 2: lavandula extracts (0.26 and 0.52 mg/mL, Group 3: 2.5%NaOCL, Group 4: 2%CHX, Group 5: Normal Saline. Irrigation was performed for each group for 5, 10 and 15 min. The viable bacteria obtained by collecting the canal dentin chips. Data analysis was performed with Kruskal-Wallis and Mann-Whitney u tests. Results: The mean number of viable bacteria was significantly reduced after 5 min exposure to lavandula solutions (p<0.05. A significant difference also existed between different times in the NaOCL group, being significant between 5 and 15 min (p<0.05, but there was no significant difference between different times in the CHX group. Comparison of the mean number of viable bacteria between different groups at different exposure times revealed that the difference between lavandula and NaOCL solutions with CHX was significant at 5 and 10 min (p<0.05, however, no statistically significant difference was observed between lavandula solutions and NaOCL. Conclusion: lavandula extract was effective in killing of EF.  Further studies are necessary to fully understand its other properties such as tissue solubility, removal of smear layer and impact on dentin structure.

  15. Treatment practices and quantification of antimicrobial drug usage in conventional and organic dairy farms in Wisconsin.

    Science.gov (United States)

    Pol, M; Ruegg, P L

    2007-01-01

    The objective of this study was to develop a method to quantify antimicrobial drug usage and treatment practices on conventional and organic dairy farms that had been recruited to represent a broad spectrum of potential exposure to antimicrobial drugs. Data on disease prevalence and treatment practices of organic (n = 20) and conventional (n = 20) farms were obtained during a farm visit using a survey instrument. A standardized estimate of antimicrobial drug usage was developed using a defined daily dose (DDD) of selected compounds. Density of antimicrobial drug usage was expressed as the number of DDD per adult cow per year. Differences in prevalence and management of selected diseases between conventional and organic farms were identified. The overall estimated prevalence of selected diseases was greater for conventional farms compared with organic farms. Organic farmers reported use of a variety of nonantimicrobial compounds for treatment and prevention of disease. Conventional farmers reported that penicillin was the compound most commonly used for dry cow therapy and cephapirin was most commonly used for treatment of clinical mastitis. On conventional farms, the estimated overall exposure to antimicrobial drugs was 5.43 DDD per cow per year composed of 3.58 and 1.85 DDD of intramammary and parenteral antimicrobial drugs, respectively. Of total intramammary antimicrobial drug usage, treatment of clinical mastitis contributed 2.02 DDD compared with 1.56 DDD attributed to the use of dry cow therapy. Of total parenteral treatments, the distribution of exposure was 0.52 (dry cow therapy), 1.43 (clinical mastitis treatment), 0.39 (treatment of foot disease), 0.14 (treatment of respiratory disease), and 0.32 (treatment of metritis) DDD. For treatments of foot infections (0.33 DDD), respiratory infections (0.07 DDD), and metritis (0.19 DDD), the mean density of ceftiofur usage was significantly greater compared with other compounds.

  16. Enhanced methanol production in plants provides broad spectrum insect resistance.

    Directory of Open Access Journals (Sweden)

    Sameer Dixit

    Full Text Available Plants naturally emit methanol as volatile organic compound. Methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. In the present study, we demonstrated that the over-expression of pectin methylesterase, derived from Arabidopsis thaliana and Aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. Methanol content in the leaves of transgenic plants was measured using proton nuclear spectroscopy (1H NMR and spectra showed up to 16 fold higher methanol as compared to control wild type (WT plants. A maximum of 100 and 85% mortality in chewing insects Helicoverpa armigera and Spodoptera litura larvae was observed, respectively when fed on transgenic plants leaves. The surviving larvae showed less feeding, severe growth retardation and could not develop into pupae. In-planta bioassay on transgenic lines showed up to 99 and 75% reduction in the population multiplication of plant sap sucking pests Myzus persicae (aphid and Bemisia tabaci (whitefly, respectively. Most of the phenotypic characters of transgenic plants were similar to WT plants. Confocal microscopy showed no deformities in cellular integrity, structure and density of stomata and trichomes of transgenic plants compared to WT. Pollen germination and tube formation was also not affected in transgenic plants. Cell wall enzyme transcript levels were comparable with WT. This study demonstrated for the first time that methanol emission can be utilized for imparting broad range insect resistance in plants.

  17. Silver nanoparticles are broad-spectrum bactericidal and virucidal compounds

    Directory of Open Access Journals (Sweden)

    Ixtepan-Turrent Liliana

    2011-08-01

    Full Text Available Abstract The advance in nanotechnology has enabled us to utilize particles in the size of the nanoscale. This has created new therapeutic horizons, and in the case of silver, the currently available data only reveals the surface of the potential benefits and the wide range of applications. Interactions between viral biomolecules and silver nanoparticles suggest that the use of nanosystems may contribute importantly for the enhancement of current prevention of infection and antiviral therapies. Recently, it has been suggested that silver nanoparticles (AgNPs bind with external membrane of lipid enveloped virus to prevent the infection. Nevertheless, the interaction of AgNPs with viruses is a largely unexplored field. AgNPs has been studied particularly on HIV where it was demonstrated the mechanism of antiviral action of the nanoparticles as well as the inhibition the transmission of HIV-1 infection in human cervix organ culture. This review discusses recent advances in the understanding of the biocidal mechanisms of action of silver Nanoparticles.

  18. Broad spectrum probiotic (Sakhabactisubtil recovered from Yakutia permafrost soil

    Directory of Open Access Journals (Sweden)

    Mikhail Petrovich Neustroev

    2011-10-01

    Full Text Available Probiotic “Sakhabactisubtil” has been developed, it has unique biological properties: frank antagonistic effect against pathogen and opportunistic microorganisms (bacteria, fungi and viruses, interferon-evoke activity, immune system enhancing effect, producing a range of ferments, beneficial microflora formation's stimulation, resistance to a number of antibiotics. [Vet. World 2011; 4(5.000: 222-224

  19. Broad Spectrum Photoelectrochemical Diodes for Solar Hydrogen Generation

    Energy Technology Data Exchange (ETDEWEB)

    Grimes, Craig A.

    2014-11-26

    Under program auspices we have investigated material chemistries suitable for the solar generation of hydrogen by water photoelectrolysis. We have built upon, and extended, our knowledge base on the synthesis and application of TiO2 nanotube arrays, a material architecture that appears ideal for water photoelectrolysis. To date we have optimized, refined, and greatly extended synthesis techniques suitable for achieving highly ordered TiO2 nanotube arrays of given length, wall thickness, pore diameter, and tube-to-tube spacing for use in water photoelectrolysis. We have built upon this knowledge based to achieve visible light responsive, photocorrosion stable n-type and p-type ternary oxide nanotube arrays for use in photoelectrochemical diodes.

  20. Studies on broad spectrum corrosion resistant oxide coatings

    Indian Academy of Sciences (India)

    Unknown

    Corrosion resistant coating materials and their application ... technology demand such corrosion resistant coatings having a ... mill additives used are as follows: China clay, 3⋅0–10⋅0; .... stage involves modification in processing of the deve-.

  1. The broad spectrum of preclinical radiobiology: British contributions

    International Nuclear Information System (INIS)

    Denekamp, Juliana

    1996-01-01

    British radiobiologists have often been at the forefront in taking clinical questions into the laboratory and in taking the results back into the clinic, i.e., what is nowadays labeled as Translational Research. They have published widely and have been very active in lectures, workshops, and discussions, forming an important component of the international communication web, both within the basic science aspects and in the translation from science to medicine, and back again. Major contributions have been made at the cellular and subcellular level, and at the level of multicellular structures, both normal and malignant. The common features of the response of cells to single doses in well-defined conditions have been used to interpret the much greater complexity of tissue and tumor responses treated with repeated small doses in a fractionated course, both of photons and other radiations, with and without chemical modifiers. The many contributions to the field of cell kinetics have provided the tools with which an understanding has been gained of the latency and evolution of radiation damage in different tissues. The prolonged interest in microenvironmental gradients and compensatory responses to injury have provided a framework for designing better radiotherapy schedules, and considerable spin-off to other branches of cancer therapy

  2. Enhanced Methanol Production in Plants Provides Broad Spectrum Insect Resistance

    Science.gov (United States)

    Dixit, Sameer; Upadhyay, Santosh Kumar; Singh, Harpal; Sidhu, Om Prakash; Verma, Praveen Chandra; K, Chandrashekar

    2013-01-01

    Plants naturally emit methanol as volatile organic compound. Methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. In the present study, we demonstrated that the over-expression of pectin methylesterase, derived from Arabidopsis thaliana and Aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. Methanol content in the leaves of transgenic plants was measured using proton nuclear spectroscopy (1H NMR) and spectra showed up to 16 fold higher methanol as compared to control wild type (WT) plants. A maximum of 100 and 85% mortality in chewing insects Helicoverpa armigera and Spodoptera litura larvae was observed, respectively when fed on transgenic plants leaves. The surviving larvae showed less feeding, severe growth retardation and could not develop into pupae. In-planta bioassay on transgenic lines showed up to 99 and 75% reduction in the population multiplication of plant sap sucking pests Myzus persicae (aphid) and Bemisia tabaci (whitefly), respectively. Most of the phenotypic characters of transgenic plants were similar to WT plants. Confocal microscopy showed no deformities in cellular integrity, structure and density of stomata and trichomes of transgenic plants compared to WT. Pollen germination and tube formation was also not affected in transgenic plants. Cell wall enzyme transcript levels were comparable with WT. This study demonstrated for the first time that methanol emission can be utilized for imparting broad range insect resistance in plants. PMID:24223989

  3. Antipneumococcal activity of ceftobiprole, a novel broad-spectrum cephalosporin.

    Science.gov (United States)

    Kosowska, Klaudia; Hoellman, Dianne B; Lin, Gengrong; Clark, Catherine; Credito, Kim; McGhee, Pamela; Dewasse, Bonifacio; Bozdogan, Bülent; Shapiro, Stuart; Appelbaum, Peter C

    2005-05-01

    Ceftobiprole (previously known as BAL9141), an anti-methicillin-resistant Staphylococcus aureus cephalosporin, was very highly active against a panel of 299 drug-susceptible and -resistant pneumococci, with MIC(50) and MIC(90) values (microg/ml) of 0.016 and 0.016 (penicillin susceptible), 0.06 and 0.5 (penicillin intermediate), and 0.5 and 1.0 (penicillin resistant). Ceftobiprole, imipenem, and ertapenem had lower MICs against all pneumococcal strains than amoxicillin, cefepime, ceftriaxone, cefotaxime, cefuroxime, or cefdinir. Macrolide and penicillin G MICs generally varied in parallel, whereas fluoroquinolone MICs did not correlate with penicillin or macrolide susceptibility or resistance. All strains were susceptible to linezolid, quinupristin-dalfopristin, daptomycin, vancomycin, and teicoplanin. Time-kill analyses showed that at 1x and 2x the MIC, ceftobiprole was bactericidal against 10/12 and 11/12 strains, respectively. Levofloxacin, moxifloxacin, vancomycin, and teicoplanin were each bactericidal against 10 to 12 strains at 2x the MIC. Azithromycin and clarithromycin were slowly bactericidal, and telithromycin was bactericidal against only 5/12 strains at 2x the MIC. Linezolid was mainly bacteriostatic, whereas quinupristin-dalfopristin and daptomycin showed marked killing at early time periods. Prolonged serial passage in the presence of subinhibitory concentrations of ceftobiprole failed to yield mutants with high MICs towards this cephalosporin, and single-passage selection showed very low frequencies of spontaneous mutants with breakthrough MICs towards ceftobiprole.

  4. Graduated diagnostics required. Broad spectrum of differential diagnoses

    International Nuclear Information System (INIS)

    Auer, I.O.

    1997-01-01

    The time lapse between initial symptoms and secured diagnosis of colitis ulcerosa still is 6-8 weeks, in case of M. Crohn even about 30 weeks. A graduated diagnostic approach is required: phase 1 relies on non-invasive methods such as anamnesis, physical examination, examination of stools, blood chemistry and sonography of the abdomen; phase 2 ecompasses endoscopy and radiological techniques, phase 3 computed tomography and MRI for detection of complications. The results of the leucodiagnosis by scintiscanning, for detection of inflammations of and out of the intestine, offer a still inhomogenous picture in terms of sensitivity and specificity. (orig./MG) [de

  5. Volatile aldehydes are promising broad-spectrum postharvest insecticides.

    Science.gov (United States)

    Hammond, D G; Rangel, S; Kubo, I

    2000-09-01

    A variety of naturally occurring aldehydes common in plants have been evaluated for their insecticidal activity and for phytotoxicity to postharvest fruits, vegetables, and grains. Twenty-nine compounds were initially screened for their activity against aphids on fava bean leaf disks. Application under reduced pressure (partial vacuum) for the first quarter of fumigation increased insecticidal activity severalfold. The 11 best aldehydes were assayed against aphids placed under the third leaf of whole heads of iceberg lettuce using the same two-tier reduced-pressure regime, which caused no additional detriment to the commodity over fumigation at atmospheric pressure. Phytotoxicity to naked and wrapped iceburg lettuce, green and red table grapes, lemon, grapefruit, orange, broccoli, avocado, cabbage, pinto bean, and rice at doses that killed 100% of aphids was recorded for three promising fumigants: propanal, (E)-2-pentenal, and 2-methyl-(E)-2-butenal. These three compounds have excellent potential as affordable postharvest insect control agents, killing 100% of the aphids with little or no detectable harm to a majority of the commodities tested. Preliminary assays indicate that similar doses are also effective against mealybugs, thrips, and whitefly.

  6. Broad-spectrum physical fitness benefits of recreational football

    DEFF Research Database (Denmark)

    Milanović, Zoran; Pantelić, Saša; Čović, Nedim

    2018-01-01

    , narrative reviews have demonstrated beneficial effects of recreational football on physical fitness and health status. OBJECTIVE: The purpose of this systematic review and meta-analysis was to evaluate the magnitude of effects of recreational football on blood pressure, body composition, lipid profile...... and muscular fitness with reference to age, gender and health status. DESIGN: Systematic review and meta-analysis. DATA SOURCES: MEDLINE, PubMed, SPORTDiscus, Web of Science, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Google Scholar were searched prior to 1 February 2017. In addition...... to a recreational football group or any other type of exercises or passive control group were included. Training programmes had to last at least 2 weeks to meet the inclusion criteria. The primary outcome measures were blood pressure, resting heart rate, body composition, muscular fitness, and blood lipids...

  7. Combinatorial materials research applied to the development of new surface coatings XIII: an investigation of polysiloxane antimicrobial coatings containing tethered quaternary ammonium salt groups.

    Science.gov (United States)

    Majumdar, Partha; Lee, Elizabeth; Gubbins, Nathan; Christianson, David A; Stafslien, Shane J; Daniels, Justin; Vanderwal, Lyndsi; Bahr, James; Chisholm, Bret J

    2009-01-01

    High-throughput biological assays were used to develop structure - antimicrobial relationships for polysiloxane coatings containing chemically bound (tethered) quaternary ammonium salt (QAS) moieties. The QAS-functional polysiloxanes were derived from solution blends of a silanol-terminated polydimethylsiloxane, a trimethoxysilane-functional QAS (QAS-TMS), and methylacetoxysilane. Since the QAS moieties provide antimicrobial activity through interaction with the microorganism cell wall, most of the compositional variables that were investigated were associated with the chemical structure of the QAS-TMS. Twenty different QAS-TMS were synthesized for the study and the antimicrobial activity of sixty unique polysiloxane coatings derived from these QAS-TMS determined toward Escherichia coli , Staphylococcus aureus , and Candida albicans . The results of the study showed that essentially all of the compositional variables significantly influenced antimicrobial activity. Surface characterization of these moisture-cured coatings using atomic force microscopy as well as water contact angle and water contact angle hysteresis measurements indicated that the compositional variables significantly affected coating surface morphology and surface chemistry. Overall, compositional variables that produced heterogeneous surface morphologies provided the highest antimicrobial activity suggesting that the antimicrobial activity was primarily derived from the relationship between coating chemical composition and self-assembly of QAS moieties at the coating/air interface. Using data modeling software, a narrow region of the compositional space was identified that provided broad-spectrum antimicrobial activity.

  8. Effect of Manuka honey, chlorhexidine gluconate and xylitol on the clinical levels of dental plaque

    Directory of Open Access Journals (Sweden)

    Prathibha A Nayak

    2010-01-01

    Full Text Available Aims: To compare the effect of Manuka honey, chlorhexidine gluconate (0.2% mouthwash and xylitol chewing gum on the dental plaque levels. Materials and Methods: Sixty healthy male dental students aged between 21 and 25 years (mean age 23.4 years participated in the study. All the subjects received a professional prophylaxis at the start of the study, with the purpose of making the dentition 100% free of plaque and calculus. The subjects were then randomly divided into three groups, i.e. the Manuka honey group, the chlorhexidine gluconate mouthwash group and the xylitol chewing gum group. Rinsing with water or any other fluid after the procedure was not allowed as also any form of mechanical oral hygiene for all the subjects during the experimental period of 72 h. After the experimental period, the plaque was disclosed using disclosing solution and their scores were recorded at six sites per tooth using the Quigley and Hein plaque index modified by Turesky-Gilmore-Glickman. Results: The mean plaque scores for Groups I, II and III were 1.37, 1.35 and 1.57, respectively. The ANOVA revealed that between-group comparison was significant, with an F-value of 5.99 and a probability value of 0.004. The T-test was carried out to evaluate the inter-group significance, which revealed that the plaque inhibition by Manuka honey was similar to that of chlorhexidine mouthwash. Both Manuka honey and chlorhexidine mouthwash reduced plaque formation significantly, better than the xylitol chewing gum. Conclusion: Manuka honey and chlorhexidine mouthwash reduced plaque formation significantly better than xylitol chewing gum.

  9. Antimicrobial activity of Schinus lentiscifolius (Anacardiaceae).

    Science.gov (United States)

    Gehrke, Ilaine T S; Neto, Alexandre T; Pedroso, Marcelo; Mostardeiro, Clarice P; Da Cruz, Ivana B M; Silva, Ubiratan F; Ilha, Vinicius; Dalcol, Ionara I; Morel, Ademir F

    2013-07-09

    Schinus lentiscifolius Marchand (syn. Schinus weinmannifolius Engl) is a plant native to Rio Grande do Sul (Southern Brazil) and has been used in Brazilian traditional medicine as antiseptic and antimicrobial for the treatment of many different health problems as well as to treat leucorrhea and to assist in ulcer and wound healing. Although it is a plant widely used by the population, there are no studies proving this popular use. The crude aqueous extract, the crude neutral methanol extract, fractions prepared from this extract (n-hexane, ethyl acetate, and n-butanol), pure compounds isolated from these fractions, and derivatives were investigated in vitro for antimicrobial activities against five Gram positive bacteria: Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Streptococcus pyogenes, three Gram negative bacteria: Escherichia coli, Pseudomonas aeruginosa, and Shigella sonnei, and four yeasts: Candida albicans, Candida tropicalis, Cryptococcus neoformans, and Saccharomyces cerevisiae. The isolated compound moronic acid, which is the most active, was tested against a range of other bacteria such as two Gram positive bacteria, namely, Bacillus cereus, Enterococcus spp, and six Gram negative bacteria, namely, Burkholderia cepacia, Providencia stuartii, Morganella morganii, Enterobacter cloacae, Enterobacter aerogenes, and Proteus mirabilis. The leaf aqueous extract (decoction) of Schinus lentiscifolius showed a broad spectrum of antibacterial activity, ranging from 125 to 250 μg/ml (MIC) against the tested bacteria and fungi. The n-hexane extract, despite being very little active against bacteria, showed an excellent antifungal activity, especially against Candida albicans (MIC=25 μg/ml), Candida tropicalis (MIC=15.5 μg/ml), and Cryptococcus neoformans, (MIC=15.5 μg/ml). From the acetate fraction (the most active against bacteria), compounds 1-6 were isolated: nonadecanol (1), moronic acid (2), gallic acid

  10. Antimicrobial activity of Aegiphila sellowiana Cham., Lamiaceae, against oral pathogens

    Directory of Open Access Journals (Sweden)

    Marcele A. Ferreira

    Full Text Available The antimicrobial activity of Aegiphila sellowiana Cham., Lamiaceae, against oral pathogens is reported. The Minimal Inhibitory Concentrations (MICs for inhibiting the microorganisms growth were determined using the broth microdilution method from the CLSI M7-A7 protocol. Chlorhexidine was used as the positive control. The ethanol crude extract of the aerial parts of A. sellowiana exhibited activity against the microorganisms tested in this work; however, the activity decreased after partition with n-hexane, dichloromethane, and ethyl acetate. Among the tested fractions, the n-hexane fraction was found to be the most effective against the evaluated oral pathogens. GC-MS analysis of this latter fraction revealed that fatty acids esters, steroids, and aliphatic sesquiterpene hydrocarbons are its major constituents. These compounds may be responsible for the activity of the n-hexane fraction, but other chemical constituents of the dichloromethane, ethyl acetate, and hydroalcoholic fraction may potentialize their activities in the crude extract.

  11. Highly potent antimicrobial peptides from N-terminal membrane-binding region of E. coli MreB.

    Science.gov (United States)

    Saikia, Karabi; Sravani, Yalavarthi Durga; Ramakrishnan, Vibin; Chaudhary, Nitin

    2017-02-23

    Microbial pathogenesis is a serious health concern. The threat escalates as the existing conventional antimicrobials are losing their efficacy against the evolving pathogens. Peptides hold promise to be developed into next-generation antibiotics. Antimicrobial peptides adopt amphipathic structures that could selectively bind to and disrupt the microbial membranes. Interaction of proteins with membranes is central to all living systems and we reasoned that the membrane-binding domains in microbial proteins could be developed into efficient antimicrobials. This is an interesting approach as self-like sequences could elude the microbial strategies of degrading the antimicrobial peptides, one of the mechanisms of showing resistance to antimicrobials. We selected the 9-residue-long membrane-binding region of E. coli MreB protein. The 9-residue peptide (C-terminal amide) and its N-terminal acetylated analog displayed broad-spectrum activity, killing Gram-negative bacteria, Gram-positive bacteria, and fungi. Extension with a tryptophan residue at the N-terminus drastically improved the activity of the peptides with lethal concentrations ≤10 μM against all the organisms tested. The tryptophan-extended peptides caused complete killing of C. albicans as well as gentamicin and methicillin resistant S. aureus at 5 μM concentration. Lipid-binding studies and electron microscopic analyses of the peptide-treated microbes suggest membrane disruption as the mechanism of killing.

  12. Dynamics of plasma levels of specific IgE in chlorhexidine allergic patients with and without accidental re-exposure

    DEFF Research Database (Denmark)

    Opstrup, Morten Schjørring; Poulsen, Lars K.; Malling, Hans Jørgen

    2016-01-01

    longer time periods is lacking and it is unknown whether levels fall below influences levels of specific IgE. OBJECTIVE: To investigate the dynamics of specific IgE in chlorhexidine allergic patients...

  13. Specialist trainees on rotation cannot replace dedicated consultant clinicians for antimicrobial stewardship of specialty disciplines

    Directory of Open Access Journals (Sweden)

    Yeo Chay Leng

    2012-11-01

    Full Text Available Abstract Our prospective-audit-and-feedback antimicrobial stewardship (AS program for hematology and oncology inpatients was switched from one led by dedicated clinicians to a rotating team of infectious diseases trainees in order to provide learning opportunities and attempt a “de-escalation” of specialist input towards a more protocol-driven implementation. However, process indicators including the number of recommendations and recommendation acceptance rates fell significantly during the year, with accompanying increases in broad-spectrum antibiotic prescription. The trends were reversed only upon reverting to the original setup. Dedicated clinicians play a crucial role in AS programs involving immunocompromised patients. Structured training and adequate succession/contingency planning is critical for sustainability.

  14. Antimicrobial Mechanisms of Macrophages and the Immune Evasion Strategies of Staphylococcus aureus

    Science.gov (United States)

    Flannagan, Ronald S.; Heit, Bryan; Heinrichs, David E.

    2015-01-01

    Habitually professional phagocytes, including macrophages, eradicate microbial invaders from the human body without overt signs of infection. Despite this, there exist select bacteria that are professional pathogens, causing significant morbidity and mortality across the globe and Staphylococcus aureus is no exception. S. aureus is a highly successful pathogen that can infect virtually every tissue that comprises the human body causing a broad spectrum of diseases. The profound pathogenic capacity of S. aureus can be attributed, in part, to its ability to elaborate a profusion of bacterial effectors that circumvent host immunity. Macrophages are important professional phagocytes that contribute to both the innate and adaptive immune response, however from in vitro and in vivo studies, it is evident that they fail to eradicate S. aureus. This review provides an overview of the antimicrobial mechanisms employed by macrophages to combat bacteria and describes the immune evasion strategies and some representative effectors that enable S. aureus to evade macrophage-mediated killing. PMID:26633519

  15. Synthesis, Characterization, and Antimicrobial Activities of Coordination Compounds of Aspartic Acid

    Directory of Open Access Journals (Sweden)

    T. O. Aiyelabola

    2016-01-01

    Full Text Available Coordination compounds of aspartic acid were synthesized in basic and acidic media, with metal ligand M : L stoichiometric ratio 1 : 2. The complexes were characterized using infrared, electronic and magnetic susceptibility measurements, and mass spectrometry. Antimicrobial activity of the compounds was determined against three Gram-positive and three Gram-negative bacteria and one fungus. The results obtained indicated that the availability of donor atoms used for coordination was a function of the pH of the solution in which the reaction was carried out. This resulted in varying geometrical structures for the complexes. The compounds exhibited a broad spectrum of activity and in some cases better activity than the standard.

  16. Synergistic antimicrobial therapy using nanoparticles and antibiotics for the treatment of multidrug-resistant bacterial infection

    Science.gov (United States)

    Gupta, Akash; Saleh, Neveen M.; Das, Riddha; Landis, Ryan F.; Bigdeli, Arafeh; Motamedchaboki, Khatereh; Rosa Campos, Alexandre; Pomeroy, Kenneth; Mahmoudi, Morteza; Rotello, Vincent M.

    2017-06-01

    Infections caused by multidrug-resistant (MDR) bacteria pose a serious global burden of mortality, causing thousands of deaths each year. Antibiotic treatment of resistant infections further contributes to the rapidly increasing number of antibiotic-resistant species and strains. Synthetic macromolecules such as nanoparticles (NPs) exhibit broad-spectrum activity against MDR species, however lack of specificity towards bacteria relative to their mammalian hosts limits their widespread therapeutic application. Here, we demonstrate synergistic antimicrobial therapy using hydrophobically functionalized NPs and fluoroquinolone antibiotics for treatment of MDR bacterial strains. An 8-16-fold decrease in antibiotic dosage is achieved in presence of engineered NPs to combat MDR strains. This strategy demonstrates the potential of using NPs to ‘revive’ antibiotics that have been rendered ineffective due to the development of resistance by pathogenic bacteria.

  17. Antimicrobial properties of coconut husk aqueous extract on cariogenic bacteria

    Directory of Open Access Journals (Sweden)

    Maria B Cyriac

    2013-01-01

    Full Text Available Background and Objectives: The husk fibers of coconut (Cocos nucifera are reported to be used by people of rural areas of South India for daily cleaning their teeth. As the beneficial effects of this plant material, with respect to antimicrobial properties against common cariogenic bacteria, are not scientifically proven, the present study was conducted. Materials and Methods: The husk of coconut was collected and aqueous extract was prepared and antimicrobial properties against common oral pathogens like Streptococcus mutans, Streptococcus salivarius, Streptococcus mitis, and Lactobacillus acidophilus were performed by agar well diffusion method. The values obtained were then subjected to statistical analysis using one way ANOVA and Tukey HSD. Results: Aqueous extract of coconut husk showed a concentration-dependent antimicrobial activity against different tested organisms with zone of inhibition ranging from 4.44 to 15.33 mms. However, the efficacy was less in comparison to chlorhexidine. Conclusion: Inhibitory action against cariogenic bacteria exhibited by aqueous extract of coconut husk indicate presence of highly effective active compounds in these extracts, which can be identified and incorporated into modern oral care systems for controlling dental caries.

  18. Antimicrobial agents are societal drugs: how should this influence prescribing?

    Science.gov (United States)

    Sarkar, Paul; Gould, Ian M

    2006-01-01

    This paper is concerned with how those who prescribe antimicrobials should consider the wider repercussions of their actions. It is accepted that in an ecological system, pressure will cause evolution; this is also the case with antimicrobials, the result being the development of resistance and the therapeutic failure of drugs. To an extent, this can be ameliorated through advances by the pharmaceutical industry, but that should not stop us from critically appraising our use and modifying our behavior to slow this process down. Up to 50% of prescribing in human medicine and 80% in veterinary medicine and farming has been considered questionable. The Alliance for the Prudent Use of Antimicrobials (APUA) was approached by the WHO to review the situation. Their recommendations include decreasing the prescribing of antibacterials for nonbacterial infections. In the UK, there has been an initiative called "the path of least resistance". This encourages general practitioners to avoid prescribing or reduce the duration of prescriptions for conditions such as upper respiratory tract infections and uncomplicated urinary tract infections; this approach has been successful. Another recommendation is to reduce the prescribing of broad-spectrum antibacterials. In UK hospitals, the problems identified with the inappropriate use of antibacterials are insufficient training in infectious disease, difficulty in selecting empirical antibacterial therapy, poor use of available microbiological information, the fear of litigation and the fact that the majority of antibacterials are prescribed by the least experienced doctors. With close liaison between the laboratories and clinicians, and the development of local protocols, this can be addressed. Another recommendation is to tighten the use of antibacterial prophylaxis and to improve patient compliance. Through a combination of improved education for doctors and patients, and improved communication skills, these problems can be

  19. In vitro post-antifungal effect (PAFE) elicited by chlorhexidine gluconate on oral isolates of Candida albicans

    OpenAIRE

    Ellepola, Arjuna N.B.; Samaranayake, Lakshman P.

    2011-01-01

    The post-antifungal effect (PAFE) is defined as the suppression of growth that persists following brief exposure of yeasts and other fungi to antimycotics and subsequent removal of the drug. There is no data available on the PAFE of chlorhexidine gluconate on oral isolates of Candida albicans. As chlorhexidine gluconate is by far the commonest antiseptic mouth wash prescribed in dentistry, the main aim of this investigation was to measure the PAFE of 10 oral isolates of C. albicans following ...

  20. Atividade antimicrobiana in vitro da cefpiroma em comparação com outros beta-lactâmicos de amplo espectro contra 804 amostras clínicas de nove hospitais brasileiros Antimicrobial activity of Cefpirome compared to other broad-spectrum Beta-Lactam drugs against 804 clinical isolates from 9 Brazilian hospitals

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    H.S. Sader

    1998-12-01

    Full Text Available OBJETIVO: Avaliar a atividade in vitro da cefalosporina de quarta geração, cefpiroma em comparação com ceftazidima, ceftriaxona, cefotaxima e imipenem em um estudo multicêntrico envolvendo nove hospitais de seis cidades em quatro estados. MATERIAL E MÉTODOS: Foram estudadas 804 amostras clínicas isoladas em pacientes internados em unidades de terapia intensiva ou unidades de oncohematologia. As amostras foram coletadas no período de junho a novembro de 1995, isto é, antes da cefpiroma estar disponível comercialmente no Brasil, e testadas através do método de microdiluição em placas conforme descrito pelo National Committee for Clinical Laboratory Standards (NCCLS. Todas as amostras resistentes à cefpiroma foram retestadas utilizando-se o E-test. RESULTADOS: Contra as amostras de enterobactérias (n= 344, a cefpiroma apresentou atividade de 2 a 32 vezes superior àquela apresentada pelas cefalosporinas de terceira geração (CTGs e semelhante àquela apresentada pelo imipenem. As porcentagens de enterobactérias sensíveis foram: 88% para a cefpiroma, 69% para as CTGs e 96% para o imipenem. O espectro de ação da cefpiroma foi maior ou igual ao do imipenem contra as espécies Citrobacter freundii, E. aerogenes, Morganella morganii e Serratia marcescens. Contra Acinetobacter sp. (n=77, a cefpiroma foi ligeiramente mais ativa que a ceftazidima, porém as porcentagens de resistência foram muito altas para esses compostos (84% e 88% respectivamente. As atividades da cefpiroma, ceftazidima e imipenem foram semelhantes contra Pseudomonas aeruginosa (n=128, com MIC50/porcentagem de sensibilidade de 8/59%, 8/62% e 4/62% respectivamente. Contra bactérias aeróbias gram-positivas, a cefpiroma foi de 4 a 16 vezes mais ativa que as CTGs. Contra S. epidermidis e outras espécies de estafilococos coagulase-negativos a cefpiroma foi ligeiramente superior ao imipenem, porém, contra as outras espécies de bactérias gram-positivas avaliadas, o imipenem apresentou atividade um pouco superior. CONCLUSÃO: Os resultados desse estudo sugerem que, no Brasil, a cefpiroma apresenta espectro de ação superior ao das CTGs contra bactérias gram-negativas (Enterobacteriaceae e não-fermentadares e gram-positivas e semelhante ao do imipenem contra algumas espécies de enterobactérias e contra P. aeruginosa.OBJECTIVE: To evaluate the in vitro activity of the fourth-generation cephalosporin cefpirome in comparison to that of ceftazidime, ceftriaxone, cefotaxime and imipenem in a multicenter study involving nine hospitals from six cities (four States. MATERIAL AND METHOD: A total of 804 isolates from patients hospitalized in either intensive care units or Oncology/Hematology units was evaluated. The isolates were collected between June and November of 1995, i.e. before cefpirome became commercially available in Brazil, and susceptibility tested by broth microdilution following the NCCLS procedures. All isolates resistant to cefpirome were retested by E-test. RESULTS: Against Enterobacteriaceae (n=344, cefpirome demonstrated an activity 2 to 32-fold higher than that of the third-generation cephalosporins (TGCs and similar to that of imipenem. The percentages of Enterobacteriaceae susceptible were: 88%, 69% and 96% for cefpirome, TGCs and imipenem, respectively. The cefpirome spectrum was greater or equal than that of imipenem against Citrobacter freundii, Enterobacter aerogenes, Morganella morganii and Serratia marcescens. Against Acinetobacter sp. (n=77, cefpirome was slightly more active than ceftazidime; however, the percentages of isolates resistant to these compounds were high (84% and 88%, respectively. The activities of cefpirome, ceftazidime and imipenem were very similar against P. aeruginosa isolates (n=128, with MIC50(mg/ml/percent susceptible of 8/59%, 8/62% and 4/62% respectively. Against aerobic gram-positive bacteria, the cefpirome activity was 4 to 16-fold higher than that of TGCs but 2 to 8-fold lower than that of imipenem. CONCLUSION: The results suggest that, in Brazil, cefpirome has a spectrum of activity which is higher than that of the TGCs against aerobic gram-negative (Enterobacteriaceae and non-Enterobacteriaceae and gram-positive bacteria and similar to that of imipenem against some Enterobacteriaceae species and P. aeruginosa.

  1. Self-assembly of cationic multidomain peptide hydrogels: supramolecular nanostructure and rheological properties dictate antimicrobial activity

    Science.gov (United States)

    Jiang, Linhai; Xu, Dawei; Sellati, Timothy J.; Dong, He

    2015-11-01

    Hydrogels are an important class of biomaterials that have been widely utilized for a variety of biomedical/medical applications. The biological performance of hydrogels, particularly those used as wound dressing could be greatly advanced if imbued with inherent antimicrobial activity capable of staving off colonization of the wound site by opportunistic bacterial pathogens. Possessing such antimicrobial properties would also protect the hydrogel itself from being adversely affected by microbial attachment to its surface. We have previously demonstrated the broad-spectrum antimicrobial activity of supramolecular assemblies of cationic multi-domain peptides (MDPs) in solution. Here, we extend the 1-D soluble supramolecular assembly to 3-D hydrogels to investigate the effect of the supramolecular nanostructure and its rheological properties on the antimicrobial activity of self-assembled hydrogels. Among designed MDPs, the bactericidal activity of peptide hydrogels was found to follow an opposite trend to that in solution. Improved antimicrobial activity of self-assembled peptide hydrogels is dictated by the combined effect of supramolecular surface chemistry and storage modulus of the bulk materials, rather than the ability of individual peptides/peptide assemblies to penetrate bacterial cell membrane as observed in solution. The structure-property-activity relationship developed through this study will provide important guidelines for designing biocompatible peptide hydrogels with built-in antimicrobial activity for various biomedical applications.Hydrogels are an important class of biomaterials that have been widely utilized for a variety of biomedical/medical applications. The biological performance of hydrogels, particularly those used as wound dressing could be greatly advanced if imbued with inherent antimicrobial activity capable of staving off colonization of the wound site by opportunistic bacterial pathogens. Possessing such antimicrobial properties would

  2. In vitro assessment of the antimicrobial effects of pomegranate (Punica granatum L. peel decoction on saliva samples

    Directory of Open Access Journals (Sweden)

    Solon José de Oliveira Leite

    2014-01-01

    Full Text Available Several products have been developed to eliminate or reduce potential pathogenic microorganisms of the oral microbiome. The continuous use of these synthetic products can result in side effects such as vomiting, diarrhea, darkening of the teeth and the induction of microbial resistance. Pomegranate (Punica granatum peel decoction was tested to assess its antimicrobial activity. In vitro analysis showed the decoction had antimicrobial activity against strains of Pseudomonas aeruginosa and Candida albicans, but none was detected against Enterococcus faecalis. When tested on saliva samples from children, the decoction showed great potential in reducing the load of microorganisms, the inhibition haloes produced with saliva samples being similar to those of the antimicrobial control (0.12% chlorhexidine. The pomegranate peel decoction in water could thus provide a promising source for developing solutions for use against oral diseases.

  3. Effectiveness of liquid soap vs. chlorhexidine gluconate for the removal of Clostridium difficile from bare hands and gloved hands.

    Science.gov (United States)

    Bettin, K; Clabots, C; Mathie, P; Willard, K; Gerding, D N

    1994-11-01

    To compare liquid soap versus 4% chlorhexidine gluconate in 4% alcohol for the decontamination of bare or gloved hands inoculated with an epidemic strain of Clostridium difficile. C difficile (6.7 log10 colony-forming units [CFU], 47% spores), was seeded onto bare or latex gloved hands of ten volunteers and allowed to dry. Half the volunteers initially washed with soap and half with chlorhexidine, followed by the other agent 1 week later. Cultures were done with Rodac plates at three sites on the hand: finger/thumbtips, the palmar surfaces of the fingers, and the palm. Statistical comparison was by paired Student's t test. On bare hands, soap and chlorhexidine did not differ in residual bacterial counts on the finger/thumbtips (log10 CFU, 2.0 and 2.1, P = NS) and fingers (log10 CFU, 2.4 and 2.5, P = NS). Counts were too high on bare palms to quantitate. On gloved hands, soap was more effective than chlorhexidine on fingers (log10 CFU 1.3 and 1.7, P soap wash than following chlorhexidine wash. These observations support the use of either soap or chlorhexidine as a handwash for removal of C difficile, but efficacy in the prevention of C difficile transmission must be determined by prospective clinical trials.

  4. The Effect of Coconut Oil pulling on Streptococcus mutans Count in Saliva in Comparison with Chlorhexidine Mouthwash.

    Science.gov (United States)

    Kaushik, Mamta; Reddy, Pallavi; Sharma, Roshni; Udameshi, Pooja; Mehra, Neha; Marwaha, Aditya

    2016-01-01

    Oil pulling is an age-old practice that has gained modern popularity in promoting oral and systemic health. The scientific verification for this practice is insufficient. Thus, this study evaluated the effect of coconut oil pulling on the count of Streptococcus mutans in saliva and to compare its efficacy with that of Chlorhexidine mouthwash: in vivo. The null hypothesis was that coconut oil pulling has no effect on the bacterial count in saliva. A randomized controlled study was planned and 60 subjects were selected. The subjects were divided into three groups, Group A: Oil pulling, Group B: Chlorhexidine, and Group C: Distilled water. Group A subjects rinsed mouth with 10 ml of coconut oil for 10 minutes. Group B subjects rinsed mouth with 5 ml Chlorhexidine mouthwash for 1 minute and Group C with 5 ml distilled water for 1 minute in the morning before brushing. Saliva samples were collected and cultured on 1st day and after 2 weeks from all subjects. Colonies were counted to compare the efficacy of coconut oil and Chlorhexidine with distilled water. Statistically significant reduction in S. mutans count was seen in both the coconut oil pulling and Chlorhexidine group. Oil pulling can be explored as a safe and effective alternative to Chlorhexidine. Edible oil-pulling therapy is natural, safe and has no side effects. Hence, it can be considered as a preventive therapy at home to maintain oral hygiene.

  5. Improving antimicrobial prescribing in Irish primary care through electronic data collection and surveillance: a feasibility study.

    Science.gov (United States)

    Galvin, Sandra; Callan, Aoife; Cormican, Martin; Duane, Sinead; Bennett, Kathleen; Murphy, Andrew W; Vellinga, Akke

    2015-07-02

    The increase in the spread of antimicrobial resistance (AMR) in bacterial pathogens and limited availability of new antimicrobials places immense pressure on general practitioners (GPs) to prescribe appropriately. Currently, electronic antimicrobial prescribing data is not routinely collected from GPs in Ireland for surveillance purposes to assess regional specific fluctuations or trends in antimicrobial prescribing. The current study aimed to address this issue by assessing the feasibility of remotely extracting antimicrobial prescribing data from primary care practices in Ireland, for the purpose of assessing prescribing quality using the European Surveillance of Antimicrobial Consumption (ESAC) drug specific quality indicators. Participating practices (n = 30) uploaded data to the Irish Primary Care Research Network (IPCRN). The IPCRN data extraction facility is integrated within the practice patient management software system and permitted the extraction of anonymised patient prescriptions for a one year period, from October 2012 to October 2013. The quality of antimicrobial prescribing was evaluated using the twelve ESAC drug specific quality indicators using the defined daily dose (DDD) per 1,000 inhabitants per day (DID) methodology. National and European prescribing surveillance data (based on total pharmacy sales) was obtained for a comparative analysis. Antimicrobial prescriptions (n = 57,079) for 27,043 patients were obtained from the thirty study practices for a one year period. On average, study practices prescribed a greater proportion of quinolones (37 % increase), in summer compared with winter months, a variation which was not observed in national and European data. In comparison with national data, study practices prescribed higher proportions of β-lactamase-sensitive penicillins (4.98 % vs. 4.3 %) and a greater use of broad spectrum compared to narrow-spectrum antimicrobials (ratio = 9.98 vs. 6.26) was observed. Study practices exceeded the

  6. Effectiveness of a mouthrinse containing active ingredients in addition to chlorhexidine and triclosan compared with chlorhexidine and triclosan rinses on plaque, gingivitis, supragingival calculus and extrinsic staining.

    Science.gov (United States)

    Kumar, S; Patel, S; Tadakamadla, J; Tibdewal, H; Duraiswamy, P; Kulkarni, S

    2013-02-01

    To assess the effectiveness of three different mouthrinses--chlorhexidine, triclosan + sodium fluoride and chlorhexidine + triclosan + sodium fluoride + zinc chloride--on plaque, calculus, gingivitis and stains and to evaluate the occurrence of adverse effects with these three treatments. Forty-eight healthy subjects participated in a double-blind, randomized, parallel experiment and were randomly allocated to any one of the three experimental mouthrinses: group A (0.2% chlorhexidine (CHX) gluconate), group B (0.03% triclosan + 0.025% sodium fluoride (NaF) + 12% ethyl alcohol) or group C (0.2% CHX + 0.3% triclosan + 0.3% NaF + 0.09% Zn chloride (ZnCl(2)). All the subjects were assessed for gingivitis, plaque, supragingival calculus and extrinsic stains at baseline and at the end of the 21-day experimental period. There was a significant difference (P = 0.046) in the effectiveness for the prevention of gingivitis and plaque, with subjects of group A and group C presenting least and highest gingival and plaque scores, respectively. Significant differences (P = 0.03) were observed for the accumulation of supragingival calculus where the deposition of calculus in group A was nearly double that of the group B, and group B was most effective in the prevention of supragingival calculus. Highest deposition of extrinsic stains was in the group A followed by group C and group B. There was no significant difference between the three treatments for adverse events' occurrence. CHX mouthrinse was most effective in controlling plaque and gingivitis but caused greatest deposition of extrinsic stains. Supragingival calculus deposition was least in triclosan + NaF group followed by CHX + triclosan + NaF + ZnCl(2) and CHX. More than half of the subjects reported adverse events during the experimental phase. © 2012 John Wiley & Sons A/S.

  7. Animation of Antimicrobial Resistance

    Medline Plus

    Full Text Available ... search Popular ... produced a nine-minute animation explaining how antimicrobial resistance both emerges and proliferates among bacteria. Over time, the use of antimicrobial drugs will ...

  8. Antimicrobial Treatments and Efficacy

    Science.gov (United States)

    To limit exposure to indoor biological contamination a risk-management approach which employs various antimicrobial treatments can effectively control contaminants and reduce exposure. Antimicrobial treatment of biological contaminants, especially mold in buildings, it is often n...

  9. Antimicrobial (Drug) Resistance

    Science.gov (United States)

    ... with facebook share with twitter share with linkedin Antimicrobial (Drug) Resistance Go to Information for Researchers ► Credit: ... and infectious diseases. Why Is the Study of Antimicrobial (Drug) Resistance a Priority for NIAID? Over time, ...

  10. Antimicrobial nanocapsules: from new solvent-free process to in vitro efficiency

    Directory of Open Access Journals (Sweden)

    Steelandt J

    2014-09-01

    Full Text Available Julie Steelandt,1 Damien Salmon,1,2 Elodie Gilbert,1 Eyad Almouazen,3 François NR Renaud,4 Laurène Roussel,1 Marek Haftek,5 Fabrice Pirot1,2 1University Claude Bernard Lyon 1, Faculty of Pharmacy, Fundamental, Clinical and Therapeutic Aspects of Skin Barrier Function, FRIPharm, Laboratoire de Pharmacie Galénique Industrielle, 2Hospital Pharmacy, FRIPharm, Hospital Edouard Herriot, Hospices Civils de Lyon, 3Laboratoire d’Automatique et de Génie des Procédés, University Claude Bernard Lyon 1, 4University Claude Bernard Lyon 1, UMR CNRS 5510/MATEIS, 5University Claude Bernard Lyon 1, Faculty of Pharmacy, Fundamental, Clinical and Therapeutic Aspects of Skin Barrier Function, FRIPharm, Laboratoire de Dermatologie, Lyon, France Abstract: Skin and mucosal infections constitute recurrent pathologies resulting from either inappropriate antiseptic procedures or a lack of efficacy of antimicrobial products. In this field, nanomaterials offer interesting antimicrobial properties (eg, long-lasting activity; intracellular and tissular penetration as compared to conventional products. The aim of this work was to produce, by a new solvent-free process, a stable and easily freeze-dryable chlorhexidine-loaded polymeric nanocapsule (CHX-NC suspension, and then to assess the antimicrobial properties of nanomaterials. The relevance of the process and the physicochemical properties of the CHX-NCs were examined by the assessment of encapsulation efficiency, stability of the nanomaterial suspension after 1 month of storage, and by analysis of granulometry and surface electric charge of nanocapsules. In vitro antimicrobial activities of the CHX-NCs and chlorhexidine digluconate solution were compared by measuring the inhibition diameters of two bacterial strains (Escherichia coli and Staphylococcus aureus and one fungal strain (Candida albicans cultured onto appropriate media. Based on the findings of this study, we report a new solvent-free process for the

  11. In vitro antimicrobial activity of Caesalpinia ferrea Martius fruits against oral pathogens.

    Science.gov (United States)

    Sampaio, Fábio C; Pereira, Maria do Socorro V; Dias, Celidarque S; Costa, Vicente Carlos O; Conde, Nikeila C O; Buzalaf, Marília A R

    2009-07-15

    In the Amazon region of Brazil, the fruits of Caesalpinia ferrea Martius (Brazilian ironwood) are widely used as an antimicrobial and healing medicine in many situations including oral infections. This study aimed to evaluate the antimicrobial activity of Caesalpinia ferrea Martius fruit extract against oral pathogens. Polyphenols estimation and spectral analysis ((1)H NMR) of the methanol extract were carried out. The microorganisms Candida albicans, Streptococcus mutans, Streptococcus salivarius, Streptococcus oralis and Lactobacillus casei were tested using the microdilution method for planktonic cells (MIC) and a multispecies biofilm model. Chlorhexidine was used as positive control. Polyphenols in the extract were estimated at 7.3% and (1)H NMR analysis revealed hydroxy phenols and methoxilated compounds. MIC values for Candida albicans, Streptococcus mutans, Streptococcus salivarius, Streptococcus oralis and Lactobacillus casei were 25.0, 40.0, 66.0, 100.0, 66.0 microg/mL, respectively. For the biofilm assay, chlorhexidine and plant extract showed no growth at 10(-4) and 10(-5) microbial dilution, respectively. At 10(-4) and 10(-5) the growth values (mean+/-SD) of the negative controls (DMSO and saline solution) for Streptococcus mutans, Streptococcus sp. and Candida albicans were 8.1+/-0.7, 7.0+/-0.6 and 5.9+/-0.9 x 10(6)CFU, respectively. Caesalpinia ferrea fruit extract can inhibit in vitro growth of oral pathogens in planktonic and biofilm models supporting its use for oral infections.

  12. Comparison of antimicrobial activities and compressive strength of alginate impression materials following disinfection procedure.

    Science.gov (United States)

    Alwahab, Zahraa

    2012-07-01

    This study investigated the effectiveness of disinfecting solution when incorporated into alginate powder instead of water against some microorganisms and on compressive strength of alginate. For measuring antimicrobial activity of alginate, 60 alginate specimens were prepared and divided into two groups: One with water incorporated in the mix (control) and the other with 0.2% chlorhexidine digluconate incorporated in the mix instead of water. The tested microorganisms were: gram +ve cocci, gram -ve bacilli and yeast (each group 10 samples). For measuring compressive strength, 20 specimens of alginate were divided into two groups: One with water incorporated in the mix (control) and the other with chlorhexidine incorporated in the mix. The statistical analysis of antimicrobial efficacy of alginate was performed with Mann-Whitney U-test, which revealed very high significant difference when comparing among groups (p 0.05). The incorporation of disinfecting agents into impression materials could serve an important role in dental laboratory infection control and it had no adverse effect on compressive strength of the hydrocolloid alginate. The risk of transmitting pathogenic microorganisms to dental laboratories via impression has been considered a topic of importance for a number of years.

  13. Antimicrobial mouthrinse use as an adjunct method in peri-implant biofilm control

    Directory of Open Access Journals (Sweden)

    Vinicius PEDRAZZI

    2014-01-01

    Full Text Available Great possibilities for oral rehabilitation emerged as a result of scientific consolidation, as well as a large number of dental implant applications. Along with implants appeared diseases such as mucositis and peri-implantitis, requiring management through several strategies applied at different stages. Biofilm accumulation is associated with clinical signs manifest by both tooth and implant inflammation. With this in mind, regular and complete biofilm elimination becomes essential for disease prevention and host protection. Chemical control of biofilms, as an adjuvant to mechanical oral hygiene, is fully justified by its simplicity and efficacy proven by studies based on clinical evidence. The purpose of this review was to present a consensus regarding the importance of antimicrobial mouthrinse use as an auxiliary method in chemical peri-implant biofilm control. The active ingredients of the several available mouthrinses include bis-biguanide, essential oils, phenols, quaternary ammonium compounds, oxygenating compounds, chlorine derivatives, plant extracts, fluorides, antibiotics and antimicrobial agent combinations. It was concluded that there is strong clinical evidence that at least two mouthrinses have scientifically proven efficacy against different oral biofilms, i.e., chlorhexidine digluconate and essential oils; however, 0.12% chlorhexidine digluconate presents a number of unwanted side effects and should be prescribed with caution. Chemical agents seem beneficial in controlling peri-implant inflammation, although they require further investigation. We recommend a scientifically proven antiseptic, with significant short and long term efficacy and with no unwanted side effects, for the prevention and/or treatment of peri-implant disease.

  14. Pulp revascularization after root canal decontamination with calcium hydroxide and 2% chlorhexidine gel.

    Science.gov (United States)

    Soares, Adriana de Jesus; Lins, Fernanda Freitas; Nagata, Juliana Yuri; Gomes, Brenda Paula Figueiredo de Almeida; Zaia, Alexandre Augusto; Ferraz, Caio Cezar Randi; de Almeida, José Flávio Affonso; de Souza-Filho, Francisco José

    2013-03-01

    Pulp revascularization may be considered a promising alternative for necrotic immature teeth. Many studies have accomplished passive decontamination associated with an antibiotic paste. To date, there is no report evaluating calcium hydroxide associated with 2% chlorhexidine gel for revascularization therapy. The aim of this case report was to describe a new proposal for pulp revascularization with mechanical decontamination and intracanal medication composed of calcium hydroxide and 2% chlorhexidine gel. The patient, a 9-year-old girl, suffered an intrusion associated with pulp exposure caused by an enamel-dentin fracture in her maxillary left central incisor. After diagnosis, treatment consisted of revascularization therapy with gentle manual instrumentation of the cervical and medium thirds of the root in addition to intracanal medication with calcium hydroxide and 2% chlorhexidine gel for 21 days. In the second session, a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate (MTA; Angelus, Londrina, Paraná, Brazil) was used for cervical sealing of the canal. Coronal sealing was performed with temporary filling material and composite resin. During the follow-up period, the root canal space showed a progressive decrease in width, mineralized tissue deposition on root canal walls, and apical closure. A cone-beam computed tomography scan taken at the 2-year follow-up confirmed these findings and did not show complete root canal calcification. This new proposal for revascularization therapy with 2% chlorhexidine gel may be used for the treatment of necrotic immature root canals. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  15. Effect of Resin Coating and Chlorhexidine on Microleakage of Two Resin Cements after Storage

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    F. Shafie

    2010-03-01

    Full Text Available Objective: Evaluating the effect of resin coating and chlorhexidine on microleakage of two resin cements after water storage.Materials and Methods: Standardized class V cavities were prepared on facial and lingual surfaces of one hundred twenty intact human molars with gingival margins placed 1mm below the cemento-enamel junction. Indirect composite inlays were fabricated and thespecimens were randomly assigned into 6 groups. In Groups 1 to 4, inlays were cemented with Panavia F2.0 cement. G1: according to the manufacturer’s instruction. G2: with light cured resin on the ED primer. G3: chlorhexidine application before priming. G4: withchlorhexidine application before priming and light cured resin on primer. G5: inlays were cemented with Nexus 2 resin cement. G6: chlorhexidine application after etching. Each group was divided into two subgroups based on the 24-hour and 6-month water storagetime. After preparation for microleakage test, the teeth were sectioned and evaluated at both margins under a 20×stereomicroscope. Dye penetration was scored using 0-3 criteria.The data was analyzed using Kruskal-Wallis and complementary Dunn tests.Results: There was significantly less leakage in G2 and G4 than the Panavia F2.0 control group at gingival margins after 6 months (P<0.05. There was no significant differences in leakage between G1 and G3 at both margins after 24 hours and 6 months storage. After 6months, G6 revealed significantly less leakage than G5 at gingival margins (P=0.033. In general, gingival margins showed more leakage than occlusal margins.Conclusion: Additionally, resin coating in self-etch (Panavia F2.0 and chlorhexidine application in etch-rinse (Nexus resin cement reduced microleakage at gingival margins after storage.

  16. Comparison of Antibacterial Effect of Fluoride and Chlorhexidine on Two Cariogenic Bacteria: An in Vitro Study

    OpenAIRE

    Poureslami HR; Barkam F; Poureslami P; Salari Z; Salari S

    2014-01-01

    Statement of problem: Dental plaque is the main source for dental caries and there is no proper vaccine that can affect dental plaques. Objectives: Daily use of an efficient anti-plaque product can be very beneficial in plaque control and, thus, prevention of caries. This study aims to evaluate the antibacterial effects of four products of Chlorhexidine and Fluoride on two types of cariogenic bacteria. Materials and Methods: In this in vitro study, the antibacterial effect of Chlorhe...

  17. A comparative evaluation of efficacy of Punica granatum and chlorhexidine on plaque and gingivitis

    Directory of Open Access Journals (Sweden)

    Sakshi Ahuja

    2011-01-01

    Full Text Available Background: Periodontal diseases are chronic bacterial infections that lead to gingival inflammation, periodontal tissue destruction, and alveolar bone loss. Acting as powerful allies in the fight against periodontal disease, natural compounds can help safeguard against lethal age-related diseases that emanate from our mouths. Punica granatum (pomegranate shrub belongs to the Punicaceae family which has been used as an astringent, hemostatic, antidiabetic, antihelmintic, and also for diarrhea and dysentery. The aim of the present work was to investigate the possible efficacy of hydroalcoholic extract from Punica granatum fruit as an antiplaque and antigingivitis agent when compared with chlorhexidine. Materials and Methods: Twenty subjects diagnosed with chronic generalized gingivitis were selected and randomly divided into two groups: Group 1 - Pomegranate mouthwash and Group 2 - Chlorhexidine mouthwash. Punica granatum mouthwash was prepared using raw Punica granatum fruit. Patients were instructed to use the prescribed mouthwash for 15 days. Clinical evaluation was undertaken using the gingival index, the plaque index, and bleeding on probing at baseline, 7 days, and 15 days. Results: The clinical study observed significant improvement in gingival status in both the sites (P<0.05. Subjects using Punica granatum mouthwash showed significant improvement in bleeding and gingivitis score as compared with chlorhexidine. In contrast, Punica granatum was shown not to be so effective in reducing plaque scores. Chlorhexidine still remains as a standard in the reduction of plaque in subjects with gingivitis. Conclusion: Punica granatum mouthwash is beneficial in improving gingival status due to its profound styptic action, with sufficient reduction in plaque scores.

  18. Effect of chlorhexidine on the adhesion of dental cements in dentin

    International Nuclear Information System (INIS)

    Carvajal Villalobos, Marco Vinicio; Torres Montoya, Jeimy; Vindas Ramirez, Cinthya Carolina

    2013-01-01

    The effect of pretreatment with 0.2% chlorhexidine was evaluated in the adhesion strength in the dentin shear of three self-adhesive cements after one week of storage. 48 healthy teeth (premolars and molars) extracted were used. The occlusal surface was removed, exposing the dentin. Self-adhesive cements RelyX U100 (3M ESPE), SpeedCEM (Ivoclar) and BisCem (Bisco) were placed in an Ultradent cylindrical abutment (2mm diameter) in dentin pretreated with 0.2% chlorhexidine for 60 seconds and in dentin without treatment for 40 seconds. Removed the cylinder all the samples were photocured an additional 40 seconds. After one week, the adhesion force was in eight groups on a universal test machine at 0.01 cm/min. The ANOVA tests were used to analyze the data. The use of chlorhexidine at 0.2% did not affect the average strength of adhesion in shear, while the type of cement if the affection [es

  19. Comparison of a chlorhexidine and a benzoyl peroxide shampoo as sole treatment in canine superficial pyoderma.

    Science.gov (United States)

    Loeffler, A; Cobb, M A; Bond, R

    2011-09-03

    The clinical and antibacterial efficacy of two shampoos used as a sole antibacterial treatment in dogs with superficial pyoderma were investigated and compared. In a randomised, partially blinded study, a 3 per cent chlorhexidine gluconate shampoo (Chlorhex 3; Leo Animal Health) was compared against a 2.5 per cent benzoyl peroxide shampoo (Paxcutol; Virbac) in 22 dogs with superficial pyoderma. Dogs were washed two to three times weekly with a 10-minute contact time over 21 days. Clinical scores and bacterial counts were assessed on days 1, 8 and 22 and compared within and between treatment groups; overall response was assessed at the end of the study. Twenty dogs completed the study; 15 (68.2 per cent) showed an overall clinical improvement and the clinical signs resolved in three chlorhexidine-treated dogs. In the chlorhexidine-treated group, scores for papules/pustules (P<0.001), investigator-assessed pruritus (P=0.003), total bacterial counts (P=0.003) and counts for coagulase-positive staphylococci (P=0.003) were reduced after three weeks. Scores and bacterial counts did not vary significantly in the benzoyl peroxide-treated group.

  20. Effects of chlorhexidine, essential oils and herbal medicines (Salvia, Chamomile, Calendula) on human fibroblast in vitro.

    Science.gov (United States)

    Wyganowska-Swiatkowska, Marzena; Urbaniak, Paulina; Szkaradkiewicz, Anna; Jankun, Jerzy; Kotwicka, Malgorzata

    2016-01-01

    Antiseptic rinses have been successfully used in inflammatory states of the gums and oral cavity mucosa. Antibacterial effects of chlorhexidine, essential oils and some herbs are well documented. Reaction of host tissue to these substances has much poorer documentation. The aim of the study was to analyse the influence of chlorhexidine (CHX), essential oil (EO: thymol, 0.064%; eucalyptol, 0.092%; methyl salicylate, 0.060%; menthol, 0.042%) mouth rinses and salvia, chamomile and calendula brews on fibroblast biology in vitro. The human fibroblast CCD16 line cells were cultured in incubation media which contained the examined substances. After 24 and 48 hours, the cell morphology, relative growth and apoptosis were evaluated. Exposure of fibroblasts to CHX, EO or salvia caused various changes in cell morphology. Cells cultured for 48 hours with CHX revealed a noticeably elongated shape of while cells cultured in high EO concentration or with salvia were considerably smaller and contracted with fewer projections. Chlorhexidine, EO and salvia reduced the fibroblast proliferation rate and stimulated cell death. Both reactions to EO were dose dependent. Cells exposure to chamomile or calendula brews did not change morphology or proliferation of fibroblasts. The results of this in vitro study showed that in contrast to chamomile and calendula, the brews of EO, CHX or salvia had a negative influence on fibroblast biology.

  1. Antimicrobial resistance in healthcare, agriculture and the environment: the biochemistry behind the headlines.

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    Venter, Henrietta; Henningsen, Michael L; Begg, Stephanie L

    2017-02-28

    The crisis of antimicrobial resistance (AMR) is one of the most serious issues facing us today. The scale of the problem is illustrated by the recent commitment of Heads of State at the UN to coordinate efforts to curb the spread of AMR infections. In this review, we explore the biochemistry behind the headlines of a few stories that were recently published in the public media. We focus on examples from three different issues related to AMR: (i) hospital-acquired infections, (ii) the spread of resistance through animals and/or the environment and (iii) the role of antimicrobial soaps and other products containing disinfectants in the dissemination of AMR. Although these stories stem from three very different settings, the underlying message in all of them is the same: there is a direct relationship between the use of antimicrobials and the development of resistance. In addition, one type of antimicrobial could select for cross-resistance to another type and/or for multidrug resistance. Therefore, we argue the case for increased stewardship to not only cover clinical use of antibiotics, but also the use of antimicrobials in agriculture and stewardship of our crucially important biocides such as chlorhexidine. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  2. Effect of Antimicrobials on Salmonella Spp. Strains Isolated from Poultry Processing Plants

    Directory of Open Access Journals (Sweden)

    L Mion

    Full Text Available ABSTRACT The routine use of antimicrobials in animal production for the treatment of infections, disease prevention, or as growth promoters is a predisposing factor for the development and dissemination of antimicrobial resistance. In food industries, sanitizers are used for the control of microbial colonization, and their efficacy depends on contact time and on the dilution of the products used. The present study assessed the effect of 12 antimicrobials and four commercial sanitizers on 18 Salmonella spp. strains isolated from poultry processing plants. None of the evaluated antimicrobials was 100% effective against the tested Salmonella spp. strains; however, 94% of the isolates were susceptible to ciprofloxacin, 77% to amoxicillin + clavulanic acid and to ampicillin, and 72% to enrofloxacin, whereas 100% of the isolates were resistant to penicillin G, 16% to tetracycline, and 11% to sulfonamide. The tested Salmonella spp. strains were 100% inhibited by peracetic acid after five minutes of contact, 0.5% by quaternary ammonium after 15 minutes, and 85.7% by chlorhexidine after 15 minutes. The results indicate the importance of testing of efficacy of antimicrobials used in animal production and in public health to monitor their action and the development of resistance.

  3. Green synthesis of silver nanoparticles from Moringa oleifera leaf extracts and its antimicrobial potential

    Science.gov (United States)

    Moodley, Jerushka S.; Babu Naidu Krishna, Suresh; Pillay, Karen; Sershen; Govender, Patrick

    2018-03-01

    In this study we report on the synthesis of silver nanoparticles (AgNPs) from the leaf extracts of Moringa oleifera using sunlight irradiation as primary source of energy, and its antimicrobial potential. Silver nanoparticle formation was confirmed by surface plasmon resonance at 450 nm and 440 nm, respectively for both fresh and freeze-dried leaf samples. Crystanality of AgNPs was confirmed by transmission electron microscopy, scanning electron microscopy with energy dispersive x-ray spectroscopy and Fourier transform infrared (FTIR) spectroscopy analysis. FTIR spectroscopic analysis suggested that flavones, terpenoids and polysaccharides predominate and are primarily responsible for the reduction and subsequent capping of AgNPs. X-ray diffraction analysis also demonstrated that the size range of AgNPs from both samples exhibited average diameters of 9 and 11 nm, respectively. Silver nanoparticles showed antimicrobial activity on both bacterial and fungal strains. The biosynthesised nanoparticle preparations from M. oleifera leaf extracts exhibit potential for application as broad-spectrum antimicrobial agents.

  4. Antimicrobial resistance of Pseudomonas spp. isolated from wastewater and wastewater-impacted marine coastal zone.

    Science.gov (United States)

    Luczkiewicz, Aneta; Kotlarska, Ewa; Artichowicz, Wojciech; Tarasewicz, Katarzyna; Fudala-Ksiazek, Sylwia

    2015-12-01

    In this study, species distribution and antimicrobial susceptibility of cultivated Pseudomonas spp. were studied in influent (INF), effluent (EFF), and marine outfall (MOut) of wastewater treatment plant (WWTP). The susceptibility was tested against 8 antimicrobial classes, active against Pseudomonas spp.: aminoglycosides, carbapenems, broad-spectrum cephalosporins from the 3rd and 4th generation, extended-spectrum penicillins, as well as their combination with the β-lactamase inhibitors, monobactams, fluoroquinolones, and polymyxins. Among identified species, resistance to all antimicrobials but colistin was shown by Pseudomonas putida, the predominant species in all sampling points. In other species, resistance was observed mainly against ceftazidime, ticarcillin, ticarcillin-clavulanate, and aztreonam, although some isolates of Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas pseudoalcaligenes, and Pseudomonas protegens showed multidrug-resistance (MDR) phenotype. Among P. putida, resistance to β-lactams and to fluoroquinolones as well as multidrug resistance become more prevalent after wastewater treatment, but the resistance rate decreased in marine water samples. Obtained data, however, suggests that Pseudomonas spp. are equipped or are able to acquire a wide range of antibiotic resistance mechanisms, and thus should be monitored as possible source of resistance genes.

  5. Mechanical, material, and antimicrobial properties of acrylic bone cement impregnated with silver nanoparticles.

    Science.gov (United States)

    Slane, Josh; Vivanco, Juan; Rose, Warren; Ploeg, Heidi-Lynn; Squire, Matthew

    2015-03-01

    Prosthetic joint infection is one of the most serious complications that can lead to failure of a total joint replacement. Recently, the rise of multidrug resistant bacteria has substantially reduced the efficacy of antibiotics that are typically incorporated into acrylic bone cement. Silver nanoparticles (AgNPs) are an attractive alternative to traditional antibiotics resulting from their broad-spectrum antimicrobial activity and low bacterial resistance. The purpose of this study, therefore, was to incorporate metallic silver nanoparticles into acrylic bone cement and quantify the effects on the cement's mechanical, material and antimicrobial properties. AgNPs at three loading ratios (0.25, 0.5, and 1.0% wt/wt) were incorporated into a commercial bone cement using a probe sonication technique. The resulting cements demonstrated mechanical and material properties that were not substantially different from the standard cement. Testing against Staphylococcus aureus and Staphylococcus epidermidis using Kirby-Bauer and time-kill assays demonstrated no antimicrobial activity against planktonic bacteria. In contrast, cements modified with AgNPs significantly reduced biofilm formation on the surface of the cement. These results indicate that AgNP-loaded cement is of high potential for use in primary arthroplasty where prevention of bacterial surface colonization is vital. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Expression and purification of antimicrobial peptide adenoregulin with C-amidated terminus in Escherichia coli.

    Science.gov (United States)

    Cao, Wei; Zhou, Yuxun; Ma, Yushu; Luo, Qingping; Wei, Dongzhi

    2005-04-01

    Adenoregulin is a 33 amino acid antimicrobial peptide isolated from the skin of the arboreal frog Phyllomedusa bicolor. Natural adenoregulin is synthesized with an amidated valine residue at C-terminus and shows lethal effects against filamentous fungi, as well as a broad spectrum of pathogenic microorganisms. A synthetic gene for adenoregulin (ADR) with an additional amino acid glutamine at C-terminus was cloned into pET32a vector to allow expression of ADR as a Trx fusion protein in Escherichia coli BL21(DE3). The resulting expression level of the fusion protein could reach up to 20% of the total cell proteins. The fusion protein could be purified effectively by Ni2+-chelating chromatography. Released from the fusion protein by enterokinase cleavage and purified to homogeneity, the recombinant ADR displayed antimicrobial activity similar to that of the synthetic ADR reported earlier. Comparing the antimicrobial activities of the recombinant adenoregulin with C-amidated terminus to that without an amidated C-terminus, we found that the amide of glutamine at C-terminus of ADR improved its potency on certain microorganisms such as Tritirachium album and Saccharomyces cerevisiae.

  7. The Road from Host-Defense Peptides to a New Generation of Antimicrobial Drugs

    Directory of Open Access Journals (Sweden)

    Alicia Boto

    2018-02-01

    Full Text Available Host-defense peptides, also called antimicrobial peptides (AMPs, whose protective action has been used by animals for millions of years, fulfill many requirements of the pharmaceutical industry, such as: (1 broad spectrum of activity; (2 unlike classic antibiotics, they induce very little resistance; (3 they act synergically with conventional antibiotics; (4 they neutralize endotoxins and are active in animal models. However, it is considered that many natural peptides are not suitable for drug development due to stability and biodisponibility problems, or high production costs. This review describes the efforts to overcome these problems and develop new antimicrobial drugs from these peptides or inspired by them. The discovery process of natural AMPs is discussed, as well as the development of synthetic analogs with improved pharmacological properties. The production of these compounds at acceptable costs, using different chemical and biotechnological methods, is also commented. Once these challenges are overcome, a new generation of versatile, potent and long-lasting antimicrobial drugs is expected.

  8. Comparison of antimicrobial peptide purification via free-flow electrophoresis and gel filtration chromatography.

    Science.gov (United States)

    Xia, Zhi-Jun; Liu, Zhen; Kong, Fan-Zhi; Fan, Liu-Yin; Xiao, Hua; Cao, Cheng-Xi

    2017-12-01

    Antimicrobial peptides (AMPs) are usually small and cationic biomolecules with broad-spectrum antimicrobial activities against pathogens. Purifying them from complex samples is essential to study their physiochemical properties. In this work, free-flow zone electrophoresis (FFZE) was utilized to purify AMPs from yeast fermentation broth. Meanwhile, gel filtration chromatography (GFC) was conducted for comparison. The separation efficiency was evaluated by SDS-PAGE analysis of the fractions from both methods. Our results demonstrated as follows: (i) FFZE had more than 30-fold higher processing capacity as compared with GFC; (ii) FFZE could achieve 87% purity and 89% recovery rate while in GFC these parameters were about 93 and 82%, respectively; (iii) the former had ∼2-fold dilution but the latter had ∼13-fold dilution. Furthermore, Tricine-SDS-PAGE, Native-PAGE, and gel IEF were carried out to characterize the purified AMPs. We found that two peptides existed as a pair with the molecular mass of ∼5.5 and 7.0 kDa, while the same pI 7.8. These two peptides were proved to have the antimicrobial activity through the standardized agar diffusion method. Therefore, FFZE could be used to continuously purify AMPs with high bioactivity, which will lead to its wide application in the clinical and pharmaceutical fields. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Blue light enhances the antimicrobial activity of honey against Pseudomonas aeruginosa

    Science.gov (United States)

    Orlandi, Viviana Teresa; Bolognese, Fabrizio; Barbieri, Paola

    2018-02-01

    Pseudomonas aeruginosa may be isolated from skin wounds of burn patients, bedsore and diabetic ulcers. The healing of wounds is often impaired by the intrinsic antibiotic resistance, the tolerance to many antimicrobials and the ability to form biofilm of this opportunistic pathogen. Finding new topical treatments to combine with antibiotics is thus essential. Among natural products, the antimicrobial properties of honeys have been known for millennia. In this study honey and visible light have been combined to control the growth of P. aeruginosa PAO1. The irradiation by a broad spectrum light source of bacteria inoculated onto 2 % w/v fir and forest honeydew (HD) honeys caused a killing effect that the honeys alone or the light alone did not show. This antimicrobial activity was light energy-dose and honey-concentration dependent. Among the tested honeys, the fir and forest HD honeys were the most efficient ones. In particular, the irradiation by blue LED (λmax = 466 nm) yielded good rates of killing, that were significantly higher in comparison to irradiation alone and honey alone. Interestingly, a similar effect was obtained by plating bacteria on blue LED pre-irradiated HD honeys. The combined use of honey and blue light was also successful in inhibiting the biofilm formation of P. aeruginosa. The blue LED irradiation of PAO1 administered with 10 % w/v forest HD honey significantly enhanced the inhibition of biofilm formation in comparison to dark incubated honey.

  10. Assessment of antimicrobial activity of c-type lysozyme from Indian shrimp Fenneropenaeus indicus

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    Viswanathan Karthik

    2014-10-01

    Full Text Available Objective: To assess the multitudinal antimicrobial effects of recombinant lysozyme from Fenneropenaeus indicus (rFi-Lyz in comparison with commercially available recombinant hen egg white lysozyme (rHEWL. Methods: Antimicrobial activity of the recombinant rFi-Lyz using several Gram positive, Gram negative bacteria and fungi in comparison with rHEWL has been evaluated. rFi-Lyz was expressed and purified using Ni2+ affinity chromatography. The effect of rFi-Lyz in the growth of yeast Candida krusei, plant molds Rhizoctonia solani and Fusarium solani was assessed by well diffusion assay in petri plates with potato dextrose agar. Results: rFi-Lyz exhibited high inhibitory activity on Gram positive bacteria such as Staphylococcus aureus and Bacillus subtilis. Among various Gram negative bacteria tested Klebsiella pneumoniae exhibited the highest inhibition followed by Pseudomonas aeruginosa and Shigella dysenteriae. rFi-Lyz also exhibited significant inhibition on two marine pathogens Aeromonas veronii and Vibrio alginolyticus. Among the various fungal strains tested, rFi-Lyz inhibited the growth of budding yeast Candida krusei significantly. Further the growth of two other plants fungus Rhizoctonia solani and Fusarium oxysporum were retarded by rFi-Lyz in the plate inhibition assay. Conclusions: rFi-Lyz exhibits a broad spectrum of antimicrobial activity like a natural antibiotic on various pathogenic bacteria and fungal strains.

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

    Directory of Open Access Journals (Sweden)

    F. Bafort

    2014-01-01

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

  12. Novel natural food antimicrobials.

    Science.gov (United States)

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

    2012-01-01

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

  13. Action of Chlorhexidine, Zingiber officinale, and Calcium Hydroxide on Candida albicans, Enterococcus faecalis, Escherichia coli, and Endotoxin in the Root Canals.

    Science.gov (United States)

    Valera, Marcia C; Oliveira, Sarah Ac; Maekawa, Lilian E; Cardoso, Flávia Gr; Chung, Adriana; Silva, Stephanie Fp; Carvalho, Cláudio At

    2016-02-01

    The purpose of this in vitro study was to evaluate the antimicrobial activity of 2% chlorhexidine gel (CHX) as auxiliary chemical substance and intracanal medications on Candida albicans, Enterococcus faecalis, Escherichia coli, and their endotoxins in the root canals. The study was conducted on 48 single-rooted human teeth divided into four groups (n = 12), according to intracanal medications used: (1) Calcium hydroxide + apyrogenic saline solution (Ca(OH)2 + SS), (2) 20% ginger glycolic extract (GEN), (3) calcium hydroxide + 20% ginger glycolic extract (Ca(OH)2 + GEN), (4) apyrogenic SS (control). Collections were made from the root canal content before preparation (baseline-S1), immediately after instrumentation (S2), 7 days after instrumentation (S3), after 14 days the action of intracanal medication (S4), and 7 days after removal of the intracanal medication (S5). The antimicrobial activity and endotoxin content were analyzed for all collections. The results were statistically analyzed by the Kruskal-Wallis and Dunn tests at a significance level of 5%. After instrumentation with CHX, there was complete elimination of E. coli and C. albicans, except for E. faecalis, which was significantly reduced and then completely eliminated after intracanal medication. There was significant reduction of endotoxin after instrumentation. Comparison of collection after instrumentation and intracanal medication revealed reduction of endotoxins in all groups; this reduction was greater in group Ca(OH)2 followed by the group GEN. It was concluded that the instrumentation using CHX and intracanal medication used were able to eliminate the microorganisms from the root canal; the endotoxins were reduced, yet not completely eliminated. This study is important and relevant for searching alternatives during endodontic therapy, since it aims to study the effect of Zingiber officinale on microorganisms and endotoxins present in root canals.

  14. Photodynamic Inactivation of Actinomyces naeslundii in Comparison With Chlorhexidine and Polyhexanide--A New Approach for Antiseptic Treatment of Medication-Related Osteonecrosis of the Jaw?

    Science.gov (United States)

    Hafner, Sigurd; Ehrenfeld, Michael; Storz, Enno; Wieser, Andreas

    2016-03-01

    Local antimicrobial therapy is a fundamental principle in the treatment of lesions of medication-related osteonecrosis of the jaw. Antimicrobial photodynamic therapy (aPDT) as a local application for the treatment of microbial infections has become more widely used in recent years. In the mouth, the bone surface is in constant contact with saliva and thus cannot be kept sterile, making the development of strategies for disinfection even more important. Different methods currently in use include local rinses with chlorhexidine (CHX), polyhexanide (PHX), or aPDT. This study compared the efficiency of these 3 methods. The in vitro activity of 3 different agents against slowly growing Actinomyces naeslundii isolated from a patient with osteonecrosis was evaluated. PHX 0.04% solution, CHX 0.12% solution, and methylene blue (MB) based dye with a laser light of 660-nm wavelength (aPDT) were compared. The decrease in colony-forming units by each method was measured using an in vitro killing assay based on a water-exposed surface in a well plate. MB dye with laser (10 seconds) decreased the bacterial load by more than 4 orders of magnitude and was superior to PHX and CHX exposure for 60 seconds. Laser exposure alone and MB dye exposure alone decreased bacterial loads slightly, but less efficiently than 60-second exposure to PHX or CHX. The most effective means of decreasing colony-forming units was achieved by a combination of laser light and dye, which also can be used clinically. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  15. Analysis of misoprostol and chlorhexidine policy gains in Pakistan: the advocacy experience of Mercy Corps Pakistan.

    Science.gov (United States)

    Sarwar, Zahida; Cutherell, Andrea; Noor, Arif; Naureen, Farah; Norman, Jennifer

    2015-11-25

    While Pakistan has made progress toward achieving Millennium Development Goal 5 for maternal health, it is unlikely to achieve the target; further, it is also not on track for Millennium Development Goal 4 regarding child health. Two low-cost, temperature stable and life-saving drugs, misoprostol and chlorhexidine, can respectively avert maternal and newborn deaths, and are particularly pertinent for poor and marginalized areas which bear the brunt of maternal and newborn deaths in Pakistan. In response, Mercy Corps led focused advocacy efforts to promote changes in policies, protocols, and regulatory environments for misoprostol (2012-2014) and for chlorhexidine (2014). These short-duration advocacy projects facilitated significant policy gains, such as inclusion of misoprostol and chlorhexidine into province-specific essential drug lists, development and endorsement of clinical protocols for the two drugs by provincial health departments, inclusion of misoprostol into pre-service training curriculum for several health cadres, and application for registration of chlorhexidine (at the concentration required for newborn care) by two pharmaceutical companies. These results were achieved by a consultative and evidence-based process which generated feedback from community members, program implementers, and policymakers, and ultimately put the government in the driver's seat to facilitate change. Community Action Dialogue forums were linked with provincial-level Technical Working Groups and Provincial Steering Committees, who passed on endorsed recommendations to the Health Secretary. The key factors which facilitated change were the identification of champions within the provincial health departments, prioritization of relationship building and follow-up, focus on concrete advocacy aims rather than broad objectives, and the use of multi-stakeholder forums to secure an enabling environment for the policy changes to take root. While these advocacy initiatives resulted in

  16. In vitro antimicrobial efficacy of Rhynchostegium vagans A. Jaeger (moss against commonly occurring pathogenic microbes of Indian sub-tropics

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    Kavita Negi*

    2016-01-01

    Full Text Available Objective: To study the antimicrobial effect of organic extracts with a standard dose of Rhynchostegium vagans (R. vagans on pathogenic bacteria and fungi. Methods: R. vagans was extracted in solvents (ethanol and acetone and the extracts were evaluated for antimicrobial activity by using disc diffusion assay. Minimum inhibitory concentration and minimum bactericidal/fungicidal concentration was observed by employing micro broth dilution method. Mode of inhibition of ethanolic extract against Aspergillus flavus var. columnaris (A. flavus var. columnaris was assessed by scanning electron microscopy. Results: It was found that the ethanolic extract of R. vagans was the most potent with lowest minimum inhibitory concentration (3.91 to 61.25 µg/mL and minimum bactericidal/fungicidal concentration (3.91 to 500 µg/mL, respectively. Significant morphological and ultrastructural alterations were seen in A. flavus var. columnaris. Among microorganisms, Gram negative bacteria (Escherichia coli, Erwinia chrysanthemi and Salmonella enterica and fungi (A. flavus var. columnaris and Aspergillus parasiticus var. globosus were found more sensitive. Ethanolic extract was found superior over the antibiotics (chloramphenicol and fluconazole. Conclusions: R. vagans exhibited effective antimicrobial activity against all the microorganisms. The moss can be used as a broad spectrum herbal antimicrobial agent in pharmaceutics.

  17. Immune mediators of sea-cucumber Holothuria tubulosa (Echinodermata) as source of novel antimicrobial and anti-staphylococcal biofilm agents.

    Science.gov (United States)

    Schillaci, Domenico; Cusimano, Maria Grazia; Cunsolo, Vincenzo; Saletti, Rosaria; Russo, Debora; Vazzana, Mirella; Vitale, Maria; Arizza, Vincenzo

    2013-06-24

    The present study aims to investigate coelomocytes, immune mediators cells in the echinoderm Holothuria tubulosa, as an unusual source of antimicrobial and antibiofilm agents. The activity of the 5kDa peptide fraction of the cytosol from H. tubulosa coelomocytes (5-HCC) was tested against a reference group of Gram-negative and Gram-positive human pathogens. Minimal inhibitory concentrations (MICs) ranging from 125 to 500 mg/ml were determined against tested strains. The observed biological activity of 5-HCC could be due to two novel peptides, identified by capillary RP-HPLC/nESI-MS/MS, which present the common chemical-physical characteristics of antimicrobial peptides. Such peptides were chemically synthesized and their antimicrobial activity was tested. The synthetic peptides showed broad-spectrum activity at 12.5 mg/ml against the majority of the tested Gram-positive and Gram-negative strains, and they were also able to inhibit biofilm formation in a significant percentage at a concentration of 3.1 mg/ml against staphylococcal and Pseudomonas aeruginosa strains.The immune mediators in H. tubulosa are a source of novel antimicrobial peptides