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      1. Author :
        Gule, N. P.; Bshena, O.; de Kwaadsteniet, M.; Cloete, T. E.; Klumperman, B.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2012
      5. Publication :
        Biomacromolecules
      6. Products :
      7. Volume :
        13
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Xen5, Xen 5, Pseudomonas aeruginosa
      12. Abstract :
        The ability of brominated furanones and other furanone compounds with 2(3H) and 2(5H) cores to inhibit bacterial adhesion of surfaces as well deactivate (destroy) them has been previously reported. The furanone derivatives 4-(2-(2-aminoethoxy)-2,5-dimethyl-3(2H)-furanone and 5-(2-(2-aminoethoxy)-ethoxy)methyl)-2(5H)-furanone were synthesized in our laboratory. These furanone derivatives were then covalently immobilized onto poly(styrene-co-maleic anhydride) (SMA) and electrospun to fabricate nonwoven nanofibrous mats with antimicrobial and cell-adhesion inhibition properties. The electrospun nanofibrous mats were tested for their ability to inhibit cell attachment by strains of bacteria commonly found in water ( Klebsiella pneumoniae Xen 39, Staphylococcus aureus Xen 36, Escherichia coli Xen 14, Pseudomonas aeruginosa Xen 5, and Salmonella tymphimurium Xen 26). Proton nuclear magnetic resonance spectroscopy ((1)H NMR), electrospray mass spectroscopy (ES-MS), and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) were used to confirm the structures of the synthesized furanones as well as their successful immobilization on SMA. To ascertain that the immobilized furanone compounds do not leach into filtered water, samples of water, filtered through the nanofibrous mats were analyzed using gas chromatography coupled with mass spectroscopy (GC-MS). The morphology of the electrospun nanofibers was characterized using scanning electron microscopy (SEM).
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/22947312
      14. Call Number :
        PKI @ kd.modi @ 5
      15. Serial :
        10550
      1. Author :
        Leszczynska, K.; Namiot, D.; Byfield, F. J.; Cruz, K.; Zendzian-Piotrowska, M.; Fein, D. E.; Savage, P. B.; Diamond, S.; McCulloch, C. A.; Janmey, P. A.; Bucki, R.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2012
      5. Publication :
        J Antimicrob Chemother
      6. Products :
      7. Volume :
        N/A
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Xen5, Xen 5, Pseudomonas aeruginosa
      12. Abstract :
        OBJECTIVES: We aim to develop antibacterial peptide mimics resistant to protease degradation, with broad-spectrum activity at sites of infection. METHODS: The bactericidal activities of LL-37, ceragenins CSA-13, CSA-90 and CSA-92 and the spermine-conjugated dexamethasone derivative D2S were evaluated using MIC and MBC measurements. Gingival fibroblast counting, interleukin-8 (IL-8) and lactate dehydrogenase (LDH) release from keratinocytes (HaCat) were used to determine effects on cell growth, pro-inflammatory response and toxicity. RESULTS: All tested cationic lipids showed stronger bactericidal activity than LL-37. Incubation of Staphylococcus aureus with half the MIC of LL-37 led to the appearance of bacteria resistant to its bactericidal effects, but identical incubations with CSA-13 or D2S did not produce resistant bacteria. Cathelicidin LL-37 significantly increased the total number of gingival fibroblasts, but ceragenins and D2S did not alter gingival fibroblast growth. Cationic lipids showed no toxicity to HaCat cells at concentrations resulting in bacterial killing. CONCLUSIONS: These data suggest that cationic lipids such as ceragenins warrant further testing as potential novel antibacterial agents.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/23134677
      14. Call Number :
        PKI @ kd.modi @ 6
      15. Serial :
        10551
      1. Author :
        Lamppa, J. W.; Ackerman, M. E.; Lai, J. I.; Scanlon, T. C.; Griswold, K. E.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2011
      5. Publication :
        PLoS One
      6. Products :
      7. Volume :
        6
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Xen5, Xen 5, Pseudomonas aeruginosa Xen 5
      12. Abstract :
        Alginate lyase enzymes represent prospective biotherapeutic agents for treating bacterial infections, particularly in the cystic fibrosis airway. To effectively deimmunize one therapeutic candidate while maintaining high level catalytic proficiency, a combined genetic engineering-PEGylation strategy was implemented. Rationally designed, site-specific PEGylation variants were constructed by orthogonal maleimide-thiol coupling chemistry. In contrast to random PEGylation of the enzyme by NHS-ester mediated chemistry, controlled mono-PEGylation of A1-III alginate lyase produced a conjugate that maintained wild type levels of activity towards a model substrate. Significantly, the PEGylated variant exhibited enhanced solution phase kinetics with bacterial alginate, the ultimate therapeutic target. The immunoreactivity of the PEGylated enzyme was compared to a wild type control using in vitro binding studies with both enzyme-specific antibodies, from immunized New Zealand white rabbits, and a single chain antibody library, derived from a human volunteer. In both cases, the PEGylated enzyme was found to be substantially less immunoreactive. Underscoring the enzyme's potential for practical utility, >90% of adherent, mucoid, Pseudomonas aeruginosa biofilms were removed from abiotic surfaces following a one hour treatment with the PEGylated variant, whereas the wild type enzyme removed only 75% of biofilms in parallel studies. In aggregate, these results demonstrate that site-specific mono-PEGylation of genetically engineered A1-III alginate lyase yielded an enzyme with enhanced performance relative to therapeutically relevant metrics.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/21340021
      14. Call Number :
        PKI @ kd.modi @ 1
      15. Serial :
        10388
      1. Author :
        Lu, Z.; Dai, T.; Huang, L.; Kurup, D. B.; Tegos, G. P.; Jahnke, A.; Wharton, T.; Hamblin, M. R.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2010
      5. Publication :
        Nanomedicine (Lond)
      6. Products :
      7. Volume :
        5
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Xen5, Xen 5, Pseudomonas aeruginosa Xen 5, Animals; Fullerenes/*chemistry; Male; Mice; Mice, Inbred BALB C; Photochemotherapy/*methods; Photosensitizing Agents/*chemistry; Pseudomonas Infections/*drug therapy; Pseudomonas aeruginosa/drug effects; Wound Infection/*drug therapy
      12. Abstract :
        AIMS: Fullerenes are under intensive study for potential biomedical applications. We have previously reported that a C60 fullerene functionalized with three dimethylpyrrolidinium groups (BF6) is a highly active broad-spectrum antimicrobial photosensitizer in vitro when combined with white-light illumination. We asked whether this high degree of in vitro activity would translate into an in vivo therapeutic effect in two potentially lethal mouse models of infected wounds. MATERIALS & METHODS: We used stable bioluminescent bacteria and a low light imaging system to follow the progress of the infection noninvasively in real time. An excisional wound on the mouse back was contaminated with one of two bioluminescent Gram-negative species, Proteus mirabilis (2.5 x 10(7) cells) and Pseudomonas aeruginosa (5 x 10(6) cells). A solution of BF6 was placed into the wound followed by delivery of up to 180 J/cm(2) of broadband white light (400-700 nm). RESULTS: In both cases there was a light-dose-dependent reduction of bioluminescence from the wound not observed in control groups (light alone or BF6 alone). Fullerene-mediated photodynamic therapy of mice infected with P. mirabilis led to 82% survival compared with 8% survival without treatment (p < 0.001). Photodynamic therapy of mice infected with highly virulent P. aeruginosa did not lead to survival, but when photodynamic therapy was combined with a suboptimal dose of the antibiotic tobramycin (6 mg/kg for 1 day) there was a synergistic therapeutic effect with a survival of 60% compared with a survival of 20% with tobramycin alone (p < 0.01). CONCLUSION: These data suggest that cationic fullerenes have clinical potential as an antimicrobial photosensitizer for superficial infections where red light is not needed to penetrate tissue.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/21143031
      14. Call Number :
        PKI @ kd.modi @ 2
      15. Serial :
        10390
      1. Author :
        Leszczynska, K.; Namiot, A.; Cruz, K.; Byfield, F. J.; Won, E.; Mendez, G.; Sokolowski, W.; Savage, P. B.; Bucki, R.; Janmey, P. A.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2011
      5. Publication :
        J Appl Microbiol
      6. Products :
      7. Volume :
        110
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Xen5, Xen 5, Pseudomonas aeruginosa Xen 5, Anti-Bacterial Agents/administration & dosage/*pharmacology/therapeutic; use; Antimicrobial Cationic Peptides/chemistry; Biofilms/drug effects; Cholic Acid/chemistry; Cystic Fibrosis/microbiology; Hemolysis/drug effects; Humans; *Poloxamer; Pseudomonas Infections/drug therapy; Pseudomonas aeruginosa/drug effects/growth & development; Skin Diseases, Bacterial/drug therapy; Staphylococcus aureus/drug effects; Steroids/administration & dosage/*pharmacology/therapeutic use; *Surface-Active Agents
      12. Abstract :
        AIMS: Ceragenin CSA-13 is a synthetic mimic of cationic antibacterial peptides, with facial amphiphilic morphology reproduced using a cholic acid scaffold. Previous data have shown that this molecule displays broad-spectrum antibacterial activity, which decreases in the presence of blood plasma. However, at higher concentrations, CSA-13 can cause lysis of erythrocytes. This study was designed to assess in vitro antibacterial and haemolytic activity of CSA-13 in the presence of pluronic F-127. METHODS AND RESULTS: CSA-13 bactericidal activity against clinical strains of bacteria associated with topical infections and in an experimental setting relevant to their pathophysiological environment, such as various epithelial tissue fluids and the airway sputum of patients suffering from cystic fibrosis (CF), was evaluated using minimum inhibitory and minimum bactericidal concentration (MIC/MBC) measurements and bacterial killing assays. We found that in the presence of pluronic F-127, CSA-13 antibacterial activity was only slightly decreased, but CSA-13 haemolytic activity was significantly inhibited. CSA-13 exhibits bacterial killing activity against clinical isolates of Staphylococcus aureus, including methicillin-resistant strains, Pseudomonas aeruginosa present in CF sputa, and biofilms formed by different Gram (+) and Gram (-) bacteria. CSA-13 bactericidal action is partially compromised in the presence of plasma, but is maintained in ascites, cerebrospinal fluid, saliva, and bronchoalveolar lavage fluid. The synergistic action of CSA-13, determined by the use of a standard checkerboard assay, reveals an increase in CSA-13 antibacterial activity in the presence of host defence molecules such as the cathelicidin LL-37 peptide, lysozyme, lactoferrin and secretory phospholipase A (sPLA). CONCLUSION: These results suggest that CSA-13 may be useful to prevent and treat topical infection. SIGNIFICANCE AND IMPACT OF THE STUDY: Combined application of CSA-13 with pluronic F-127 may be beneficial by reducing CSA-13 toxicity.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/20961363
      14. Call Number :
        PKI @ kd.modi @ 3
      15. Serial :
        10389
      1. Author :
        Gule, N. P.; de Kwaadsteniet, M.; Cloete, T. E.; Klumperman, B.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2012
      5. Publication :
        Water Res
      6. Products :
      7. Volume :
        N/A
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Xen5, Xen39, Xen26, Xen14, Xen36, Xen 5, Xen 39, Xen 26, Xen 14, Xen 36, Psuedomonas aeruginosa, S. aureus, Klebsiella, E. coli, Salmonella,
      12. Abstract :
        The 3(2H) furanone derivative 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) was investigated for its antimicrobial and cell-adhesion inhibition properties against Klebsiella pneumoniae Xen 39, Staphylococcus aureus Xen 36, Escherichia coli Xen 14, Pseudomonas aeruginosa Xen 5 and Salmonella typhimurium Xen 26. Nanofibers electrospun from solution blends of DMHF and poly(vinyl alcohol) (PVA) were tested for their ability to inhibit surface-attachment of bacteria. Antimicrobial and adhesion inhibition activity was determined via the plate counting technique. To quantify viable but non-culturable cells and to validate the plate counting results, bioluminescence and fluorescence studies were carried out. Nanofiber production was upscaled using the bubble electrospinning technique. To ascertain that no DMHF leached into filtered water, samples of water filtered through the nanofibrous mats were analyzed using gas chromatography coupled with mass spectrometry (GC-MS). Scanning electron microscopy (SEM) and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) were used to characterize the electrospun nanofibers.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/23261340
      14. Call Number :
        PKI @ kd.modi @ 7
      15. Serial :
        10548
      1. Author :
        Gule, N. P.; de Kwaadsteniet, M.; Cloete, T. E.; Klumperman, B.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2012
      5. Publication :
        Water Res
      6. Products :
      7. Volume :
        N/A
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Xen5, Xen39, Xen26, Xen14, Xen36, Xen 5, Xen 39, Xen 26, Xen 14, Xen 36, Psuedomonas aeruginosa, S. aureus, Klebsiella, E. coli, Salmonella,
      12. Abstract :
        The 3(2H) furanone derivative 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) was investigated for its antimicrobial and cell-adhesion inhibition properties against Klebsiella pneumoniae Xen 39, Staphylococcus aureus Xen 36, Escherichia coli Xen 14, Pseudomonas aeruginosa Xen 5 and Salmonella typhimurium Xen 26. Nanofibers electrospun from solution blends of DMHF and poly(vinyl alcohol) (PVA) were tested for their ability to inhibit surface-attachment of bacteria. Antimicrobial and adhesion inhibition activity was determined via the plate counting technique. To quantify viable but non-culturable cells and to validate the plate counting results, bioluminescence and fluorescence studies were carried out. Nanofiber production was upscaled using the bubble electrospinning technique. To ascertain that no DMHF leached into filtered water, samples of water filtered through the nanofibrous mats were analyzed using gas chromatography coupled with mass spectrometry (GC-MS). Scanning electron microscopy (SEM) and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) were used to characterize the electrospun nanofibers.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/23261340
      14. Call Number :
        PKI @ kd.modi @ 8
      15. Serial :
        10549
      1. Author :
        Lorentzen, D.; Durairaj, L.; Pezzulo, A. A.; Nakano, Y.; Launspach, J.; Stoltz, D. A.; Zamba, G.; McCray, P. B., Jr.; Zabner, J.; Welsh, M. J.; Nauseef, W. M.; Banfi, B.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2011
      5. Publication :
        Free Radic Biol Med
      6. Products :
      7. Volume :
        50
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Xen8.1, Xen 8.1, S. aureus, IVIS, bioluminescence imaging
      12. Abstract :
        A recently discovered enzyme system produces antibacterial hypothiocyanite (OSCN(-)) in the airway lumen by oxidizing the secreted precursor thiocyanate (SCN(-)). Airway epithelial cultures have been shown to secrete SCN(-) in a CFTR-dependent manner. Thus, reduced SCN(-) availability in the airway might contribute to the pathogenesis of cystic fibrosis (CF), a disease caused by mutations in the CFTR gene and characterized by an airway host defense defect. We tested this hypothesis by analyzing the SCN(-) concentration in the nasal airway surface liquid (ASL) of CF patients and non-CF subjects and in the tracheobronchial ASL of CFTR-DeltaF508 homozygous pigs and control littermates. In the nasal ASL, the SCN(-) concentration was ~30-fold higher than in serum independent of the CFTR mutation status of the human subject. In the tracheobronchial ASL of CF pigs, the SCN(-) concentration was somewhat reduced. Among human subjects, SCN(-) concentrations in the ASL varied from person to person independent of CFTR expression, and CF patients with high SCN(-) levels had better lung function than those with low SCN(-) levels. Thus, although CFTR can contribute to SCN(-) transport, it is not indispensable for the high SCN(-) concentration in ASL. The correlation between lung function and SCN(-) concentration in CF patients may reflect a beneficial role for SCN(-).
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/21334431
      14. Call Number :
        PKI @ kd.modi @ 1
      15. Serial :
        10564
      1. Author :
        Yipp, B. G.; Petri, B.; Salina, D.; Jenne, C. N.; Scott, B. N.; Zbytnuik, L. D.; Pittman, K.; Asaduzzaman, M.; Wu, K.; Meijndert, H. C.; Malawista, S. E.; de Boisfleury Chevance, A.; Zhang, K.; Conly, J.; Kubes, P.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2012
      5. Publication :
        Nat Med
      6. Products :
      7. Volume :
        18
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Xen8.1, Xen 8.1, S. aureus, IVIS, bioluminescence imaging, Analysis of Variance; Animals; Extracellular Space/*metabolism; Genetic Vectors/genetics; Green Fluorescent Proteins/metabolism; Humans; Mice; Mice, Inbred C57BL; Mice, Transgenic; Microscopy, Confocal; Microscopy, Electron, Transmission; Microscopy, Fluorescence; Movement/*physiology; Neutrophils/*immunology/metabolism/physiology; Opsonin Proteins/metabolism; Skin Diseases, Bacterial/*immunology/metabolism; Toll-Like Receptor 2/metabolism
      12. Abstract :
        Neutrophil extracellular traps (NETs) are released as neutrophils die in vitro in a process requiring hours, leaving a temporal gap that invasive microbes may exploit. Neutrophils capable of migration and phagocytosis while undergoing NETosis have not been documented. During Gram-positive skin infections, we directly visualized live polymorphonuclear cells (PMNs) in vivo rapidly releasing NETs, which prevented systemic bacterial dissemination. NETosis occurred during crawling, thereby casting large areas of NETs. NET-releasing PMNs developed diffuse decondensed nuclei, ultimately becoming devoid of DNA. Cells with abnormal nuclei showed unusual crawling behavior highlighted by erratic pseudopods and hyperpolarization consistent with the nucleus being a fulcrum for crawling. A requirement for both Toll-like receptor 2 and complement-mediated opsonization tightly regulated NET release. Additionally, live human PMNs injected into mouse skin developed decondensed nuclei and formed NETS in vivo, and intact anuclear neutrophils were abundant in Gram-positive human abscesses. Therefore early in infection NETosis involves neutrophils that do not undergo lysis and retain the ability to multitask.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/22922410
      14. Call Number :
        PKI @ kd.modi @ 2
      15. Serial :
        10565