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      1. Author :
        Hart, Emily; Azzopardi, Kristy; Taing, Heng; Graichen, Florian; Jeffery, Justine; Mayadunne, Roshan; Wickramaratna, Malsha; O'Shea, Mike; Nijagal, Brunda; Watkinson, Rebecca; O'Leary, Stephen; Finnin, Barrie; Tait, Russell; Robins-Browne, Roy
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2010
      5. Publication :
        The Journal of antimicrobial chemotherapy
      6. Products :
      7. Volume :
        65
      8. Issue :
        5
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Animals; Anti-Bacterial Agents; Bioware; Colony Count, Microbial; Disease Models, Animal; Female; Foreign Bodies; Humans; Mice; Mice, Inbred BALB C; Ofloxacin; Polymers; Prosthesis-Related Infections; Staphylococcal Infections; Staphylococcus aureus; Xen29
      12. Abstract :
        OBJECTIVES To assess support discs, comprising polyethylene terephthalate (PET), coated with different polymer/levofloxacin combinations for antimicrobial activity in an animal model of infection, in order to explore the use of specific polymer coatings incorporating levofloxacin as a means of reducing device-related infections. METHODS Aliphatic polyester-polyurethanes containing different ratios of poly(lactic acid) diol and poly(caprolactone) diol were prepared, blended with levofloxacin and then used to coat support discs. The in vitro levofloxacin release profiles from these discs were measured in aqueous solution. Mice were surgically implanted with the coated discs placed subcutaneously and infection was initiated by injection of 10(6) cfu of Staphylococcus aureus into the subcutaneous pocket containing the implant. After 5, 10, 20 and 30 days, the discs were removed, and the number of bacteria adhering to the implant and the residual antimicrobial activity of the discs were determined. RESULTS In vitro, the release of levofloxacin from the coated discs occurred at a constant rate and then reached a plateau at different timepoints, depending on the polymer preparation used. In vivo, none of the discs coated with polymer blends containing levofloxacin was colonized by S. aureus, whereas 94% of the discs coated with polymer alone were infected. All discs coated with levofloxacin-blended polymers displayed residual antimicrobial activity for at least 20 days post-implantation. CONCLUSIONS Bioerodable polyester-polyurethane polymer coatings containing levofloxacin can prevent bacterial colonization of implants in an intra-operative model of device-related infections.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/20233779
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9035
      1. Author :
        N/A
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2010
      5. Publication :
        Annals of the New York Academy of Sciences
      6. Products :
      7. Volume :
        1192
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Animals; Biofilms; Bioware; Bone Density Conservation Agents; Chronic Disease; Cytokines; Drug Evaluation, Preclinical; Humans; Immunity; Incidence; Jaw Diseases; Mice; Neovascularization, Physiologic; Osteoclasts; Osteomyelitis; Osteonecrosis; Staphylococcal Infections; Xen29
      12. Abstract :
        The effects of antiresorptive agents (e.g., alendronate [Aln], osteoprotegerin [OPG]) on bone infection are unknown. Thus, their effects on implant-associated osteomyelitis (OM) were investigated in mice using PBS (placebo), gentamycin, and etanercept (TNFR:Fc) controls. None of the drugs affected humoral immunity, angiogenesis, or chronic infection. However, the significant (P < 0.05 vs. PBS) inhibition of cortical osteolysis and decreased draining lymph node size in Aln- and OPG-treated mice was associated with a significant (P < 0.05) increase in the incidence of high-grade infections during the establishment of OM. In contrast, the high-grade infections in TNFR:Fc-treated mice were associated with immunosuppression, as evidenced by the absence of granulomas and presence of Gram(+) biofilm in the bone marrow. Collectively, these findings indicate that although antiresorptive agents do not exacerbate chronic OM, they can increase the bacterial load during early infection by decreasing lymphatic drainage and preventing the removal of necrotic bone that harbors the bacteria.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/20392222
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9034
      1. Author :
        N/A
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2010
      5. Publication :
        Journal of immunology (Baltimore, Md.: 1950)
      6. Products :
      7. Volume :
        184
      8. Issue :
        5
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Amino Acid Sequence; Animals; Antimicrobial Cationic Peptides; Bacterial Infections; Bioware; Cell Line; Cells, Cultured; Chemokine CCL2; Chemokine CCL7; Chemokine CXCL1; Chemokines; Female; Humans; Interleukin-8; Leukocytes; Leukocytes, Mononuclear; Macrophages; Mice; Mice, Inbred C57BL; Molecular Sequence Data; NF-kappa B; p38 Mitogen-Activated Protein Kinases; Phosphatidylinositol 3-Kinases; Phosphorylation; Staphylococcal Infections; Staphylococcus aureus; Xen29, Xen14
      12. Abstract :
        With the rapid rise in the incidence of multidrug resistant infections, there is substantial interest in host defense peptides as templates for production of new antimicrobial therapeutics. Natural peptides are multifunctional mediators of the innate immune response, with some direct antimicrobial activity and diverse immunomodulatory properties. We have previously developed an innate defense regulator (IDR) 1, with protective activity against bacterial infection mediated entirely through its effects on the immunity of the host, as a novel approach to anti-infective therapy. In this study, an immunomodulatory peptide IDR-1002 was selected from a library of bactenecin derivatives based on its substantially more potent ability to induce chemokines in human PBMCs. The enhanced chemokine induction activity of the peptide in vitro correlated with stronger protective activity in vivo in the Staphylococcus aureus-invasive infection model, with a >5-fold reduction in the protective dose in direct comparison with IDR-1. IDR-1002 also afforded protection against the Gram-negative bacterial pathogen Escherichia coli. Chemokine induction by IDR-1002 was found to be mediated through a Gi-coupled receptor and the PI3K, NF-kappaB, and MAPK signaling pathways. The protective activity of the peptide was associated with in vivo augmentation of chemokine production and recruitment of neutrophils and monocytes to the site of infection. These results highlight the importance of the chemokine induction activity of host defense peptides and demonstrate that the optimization of the ex vivo chemokine-induction properties of peptides is a promising method for the rational development of immunomodulatory IDR peptides with enhanced anti-infective activity.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/20107187
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9033
      1. Author :
        N/A
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2007
      5. Publication :
        PloS one
      6. Products :
      7. Volume :
        2
      8. Issue :
        2
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Adhesins, Bacterial; Animals; Antigens, CD46; Bacteremia; Bacterial Outer Membrane Proteins; Bacterial Proteins; Bacterial Translocation; Bioware; Blood-Brain Barrier; Central Nervous System; Disease Progression; Female; Luminescent Measurements; Luminescent Proteins; Male; Meningitis, Meningococcal; Meningococcal Infections; Mice; Mice, Transgenic; Nasal Cavity; pXen-13; Recombinant Fusion Proteins; Respiratory System; Sepsis; Thyroid Gland
      12. Abstract :
        Neisseria meningitidis is a human pathogen that causes septicemia and meningitis with high mortality. The disease progression is rapid and much remains unknown about the disease process. The understanding of disease development is crucial for development of novel therapeutic strategies and vaccines against meningococcal disease. The use of bioluminescent imaging combined with a mouse disease model allowed us to investigate the progression of meningococcal sepsis over time. Injection of bacteria in blood demonstrated waves of bacterial clearance and growth, which selected for Opa-expressing bacteria, indicating the importance of this bacterial protein. Further, N. meningitidis accumulated in the thyroid gland, while thyroid hormone T4 levels decreased. Bacteria reached the mucosal surfaces of the upper respiratory tract, which required expression of the meningococcal PilC1 adhesin. Surprisingly, PilC1 was dispensable for meningococcal growth in blood and for crossing of the blood-brain barrier, indicating that the major role of PilC1 is to interact with mucosal surfaces. This in vivo study reveals disease dynamics and organ targeting during meningococcal disease and presents a potent tool for further investigations of meningococcal pathogenesis and vaccines in vivo. This might lead to development of new strategies to improve the outcome of meningococcal disease in human patients.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/17311106
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9032
      1. Author :
        Woelfle, Mark A; Xu, Yao; Qin, Ximing; Johnson, Carl Hirschie
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2007
      5. Publication :
        Proceedings of the National Academy of Sciences of the United States of America
      6. Products :
      7. Volume :
        104
      8. Issue :
        47
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Bioware; Circadian Rhythm; Cyanobacteria; DNA, Bacterial; DNA, Superhelical; Gene Expression Regulation, Bacterial; Light; Plasmids; Promoter Regions, Genetic; pXen-13; Transcription, Genetic
      12. Abstract :
        The cyanobacterium Synechococcus elongatus expresses robust circadian (daily) rhythms under the control of the KaiABC-based core clockwork. Unlike eukaryotic circadian systems characterized thus far, the cyanobacterial clockwork modulates gene expression patterns globally and specific clock gene promoters are not necessary in mediating the circadian feedback loop. The oscilloid model postulates that global rhythms of transcription are based on rhythmic changes in the status of the cyanobacterial chromosome that are ultimately controlled by the KaiABC oscillator. By using a nonessential, cryptic plasmid (pANS) as a reporter of the superhelical state of DNA in cyanobacteria, we show that the supercoiling status of this plasmid changes in a circadian manner in vivo. The rhythm of topological change in the plasmid is conditional; this change is rhythmic in constant light and in light/dark cycles, but not in constant darkness. In further support of the oscilloid model, cyanobacterial promoters that are removed from their native chromosomal locations and placed on a plasmid preserve their circadian expression patterns.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/18000054
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9031
      1. Author :
        Rambow-Larsen, Amy A; Rajashekara, Gireesh; Petersen, Erik; Splitter, Gary
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2008
      5. Publication :
        Journal of bacteriology
      6. Products :
      7. Volume :
        190
      8. Issue :
        9
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Amino Acid Sequence; Animals; Bioware; Brucella melitensis; Brucellosis; Disease Models, Animal; Flagella; Gene Deletion; Gene Expression Regulation, Bacterial; Interferon Regulatory Factor-1; Macrophages; Mice; Mice, Mutant Strains; Molecular Sequence Data; Oligonucleotide Array Sequence Analysis; pXen-13; Quorum Sensing; Repressor Proteins; Trans-Activators; Virulence Factors
      12. Abstract :
        Brucella melitensis is an intracellular pathogen that establishes a replicative niche within macrophages. While the intracellular lifestyle of Brucella is poorly understood and few virulence factors have been identified, components of a quorum-sensing pathway in Brucella have recently been identified. The LuxR-type regulatory protein, VjbR, and an N-acylhomoserine lactone signaling molecule are both involved in regulating expression of the virB-encoded type IV secretion system. We have identified a second LuxR-type regulatory protein (BlxR) in Brucella. Microarray analysis of a blxR mutant suggests that BlxR regulates the expression of a number of genes, including those encoding the type IV secretion system and flagella. Confirming these results, deletion of blxR in B. melitensis reduced the transcriptional activities of promoters for the virB operon, flagellar genes, and another putative virulence factor gene, bopA. Furthermore, our data suggested that both BlxR and VjbR are positively autoregulated and cross-regulate the expression of each other. The blxR deletion strain exhibited reduced growth in macrophages, similar to that observed for a vjbR deletion strain. However, unlike the vjbR deletion, the blxR deletion did not fully attenuate virulence in mice. More strikingly, bioluminescent imaging revealed that dissemination of the blxR mutant was similar to that of wild-type B. melitensis, while the vjbR mutant was defective for systemic spread in IRF-1(-/-) mice, suggesting that these regulators are not functionally redundant but that they converge in a common pathway regulating bacterial processes.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/18310341
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9030
      1. Author :
        Harms, Jerome S; Durward, Marina A; Magnani, Diogo M; Splitter, Gary A
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2009
      5. Publication :
        Journal of immune based therapies and vaccines
      6. Products :
      7. Volume :
        7
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Bioware; pXen-13
      12. Abstract :
        BACKGROUND There is no safe, effective human vaccine against brucellosis. Live attenuated Brucella strains are widely used to vaccinate animals. However these live Brucella vaccines can cause disease and are unsafe for humans. Killed Brucella or subunit vaccines are not effective in eliciting long term protection. In this study, we evaluate an approach using a live, non-pathogenic bacteria (E. coli) genetically engineered to mimic the brucellae pathway of infection and present antigens for an appropriate cytolitic T cell response. METHODS E. coli was modified to express invasin of Yersinia and listerialysin O (LLO) of Listeria to impart the necessary infectivity and antigen releasing traits of the intracellular pathogen, Brucella. This modified E. coli was considered our vaccine delivery system and was engineered to express Green Fluorescent Protein (GFP) or Brucella antigens for in vitro and in vivo immunological studies including cytokine profiling and cytotoxicity assays. RESULTS The E. coli vaccine vector was able to infect all cells tested and efficiently deliver therapeutics to the host cell. Using GFP as antigen, we demonstrate that the E. coli vaccine vector elicits a Th1 cytokine profile in both primary and secondary immune responses. Additionally, using this vector to deliver a Brucella antigen, we demonstrate the ability of the E. coli vaccine vector to induce specific Cytotoxic T Lymphocytes (CTLs). CONCLUSION Protection against most intracellular bacterial pathogens can be obtained mostly through cell mediated immunity. Data presented here suggest modified E. coli can be used as a vaccine vector for delivery of antigens and therapeutics mimicking the infection of the pathogen and inducing cell mediated immunity to that pathogen.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/19126207
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9029
      1. Author :
        Xu, Xiulan; Miller, Sally A; Baysal-Gurel, Fulya; Gartemann, Karl-Heinz; Eichenlaub, Rudolf; Rajashekara, Gireesh
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2010
      5. Publication :
        Applied and environmental microbiology
      6. Products :
      7. Volume :
        76
      8. Issue :
        12
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Actinomycetales; Bioware; Genes, Reporter; Genetic Engineering; Luminescent Proteins; Lycopersicon esculentum; Mirabilis; Plant Diseases; pXen-13; Recombinant Proteins; Seeds; Staining and Labeling
      12. Abstract :
        Clavibacter michiganensis subsp. michiganensis is a Gram-positive bacterium that causes wilting and cankers, leading to severe economic losses in commercial tomato production worldwide. The disease is transmitted from infected seeds to seedlings and mechanically from plant to plant during seedling production, grafting, pruning, and harvesting. Because of the lack of tools for genetic manipulation, very little is known regarding the mechanisms of seed and seedling infection and movement of C. michiganensis subsp. michiganensis in grafted plants, two focal points for application of bacterial canker control measures in tomato. To facilitate studies on the C. michiganensis subsp. michiganensis movement in tomato seed and grafted plants, we isolated a bioluminescent C. michiganensis subsp. michiganensis strain using the modified Tn1409 containing a promoterless lux reporter. A total of 19 bioluminescent C. michiganensis subsp. michiganensis mutants were obtained. All mutants tested induced a hypersensitive response in Mirabilis jalapa and caused wilting of tomato plants. Real-time colonization studies of germinating seeds using a virulent, stable, constitutively bioluminescent strain, BL-Cmm17, showed that C. michiganensis subsp. michiganensis aggregated on hypocotyls and cotyledons at an early stage of germination. In grafted seedlings in which either the rootstock or scion was exposed to BL-Cmm17 via a contaminated grafting knife, bacteria were translocated in both directions from the graft union at higher inoculum doses. These results emphasize the use of bioluminescent C. michiganensis subsp. michiganensis to help better elucidate the C. michiganensis subsp. michiganensis-tomato plant interactions. Further, we demonstrated the broader applicability of this tool by successful transformation of C. michiganensis subsp. nebraskensis with Tn1409::lux. Thus, our approach would be highly useful to understand the pathogenesis of diseases caused by other subspecies of the agriculturally important C. michiganensis.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/20400561
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9028
      1. Author :
        Francis, K P; Yu, J; Bellinger-Kawahara, C; Joh, D; Hawkinson, M J; Xiao, G; Purchio, T F; Caparon, M G; Lipsitch, M; Contag, P R
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2001
      5. Publication :
        Infection and immunity
      6. Products :
      7. Volume :
        69
      8. Issue :
        5
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Amoxicillin; Animals; Bioware; DNA Transposable Elements; Female; Luminescent Measurements; Lung; Mice; Mice, Inbred BALB C; Nasopharynx; Operon; Promoter Regions, Genetic; pXen-5; Streptococcus pneumoniae; Transformation, Bacterial, Xen10, Xen7
      12. Abstract :
        Animal studies with Streptococcus pneumoniae have provided valuable models for drug development. In order to monitor long-term pneumococcal infections noninvasively in living mice, a novel gram-positive lux transposon cassette, Tn4001 luxABCDE Km(r), that allows random integration of lux genes onto the bacterial chromosome was constructed. The cassette was designed so that the luxABCDE and kanamycin resistance genes were linked to form a single promoterless operon. Bioluminescence and kanamycin resistance only occur in a bacterial cell if this operon has transposed downstream of a promoter on the bacterium's chromosome. S. pneumoniae D39 was transformed with plasmid pAUL-A Tn4001 luxABCDE Km(r), and a number of highly bioluminescent colonies were recovered. Genomic DNA from the brightest D39 strain was used to transform a number of clinical S. pneumoniae isolates, and several of these strains were tested in animal models, including a pneumococcal lung infection model. Strong bioluminescent signals were seen in the lungs of the animals containing these pneumococci, allowing the course and antibiotic treatment of the infections to be readily monitored in real time in the living animals. Recovery of the bacteria from the animals showed that the bioluminescent signal corresponded to the number of CFU and that the lux construct was highly stable even after several days in vivo. We believe that this lux transposon will greatly expand the ability to evaluate drug efficacy against gram-positive bacteria in living animals using bioluminescence.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/11292758
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9027
      1. Author :
        Orihuela, Carlos J; Gao, Geli; McGee, Mackenzie; Yu, Jun; Francis, Kevin P; Tuomanen, Elaine
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2003
      5. Publication :
        Scandinavian journal of infectious diseases
      6. Products :
      7. Volume :
        35
      8. Issue :
        9
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Animals; Bioware; Disease Models, Animal; Female; Lung; Mice; Mice, Inbred BALB C; Pneumococcal Infections; pXen-5; Serotyping; Streptococcus pneumoniae, Xen10, Xen7, Xen35
      12. Abstract :
        The variability of the course of infection by Streptococcus pneumoniae is well known but poorly understood. Most animal models of pneumonia, sepsis or meningitis have been forced to use site-specific bacterial inoculation to mimic localized human infection. This study examined the differences in the progression of disease-causing strains D39 (serotype 2), A66.1 (serotype 3) and TIGR4 (serotype 4) using isolates transformed with the Gram-positive lux transposon cassette, Tn4001 luxABCDE Km(r). Expression of the lux operon results in bioluminescence, permitting the detection of the bacteria within a living animal while using a CCD camera. Mice infected intranasally with A66.1 developed only pneumonia, those challenged with D39 experienced high-grade sepsis, while TIGR4 infection resulted in low-grade pneumonia and bacteremia ultimately progressing to meningitis. Quantitative analysis of bacterial titers confirmed these patterns, which were consistent across different lineages of mice. Mice anesthetized with ketamine and xylazine developed more severe forms of the disease compared with isoflurane. These studies unambiguously characterize 3 distinct models of the natural course of pneumococcal infection. Mapping these models provides a framework for detailed molecular modeling of pneumococcal virulence determinants at specific stages of disease.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/14620149
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9026