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      1. Author :
        Johnson, J. L.; Pillai, S.; Pernazza, D.; Sebti, S. M.; Lawrence, N. J.; Chellappan, S. P.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2012
      5. Publication :
        Cancer Res
      6. Products :
      7. Volume :
        72
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        A549-luc-C8, A549-luc, IVIS, Bioware, Animals; Breast Neoplasms/genetics/metabolism/pathology; Carcinoma, Non-Small-Cell Lung/genetics/metabolism/pathology; Cell Line, Tumor; E2F Transcription Factors/*genetics/metabolism; Enzyme Assays/methods; Female; Gelatin/metabolism; *Gene Expression Regulation, Enzymologic; *Gene Expression Regulation, Neoplastic; Humans; Lung Neoplasms/genetics/metabolism/pathology; Matrix Metalloproteinases/biosynthesis/*genetics/metabolism; Mice; Mice, SCID; Neoplasm Metastasis; Phosphatidylethanolamine Binding Protein/*metabolism; Retinoblastoma Protein/genetics/*metabolism; Transcription, Genetic; Transfection
      12. Abstract :
        The retinoblastoma (Rb)-E2F transcriptional regulatory pathway plays a major role in cell-cycle regulation, but its role in invasion and metastasis is less well understood. We find that many genes involved in the invasion of cancer cells, such as matrix metalloproteinases (MMP), have potential E2F-binding sites in their promoters. E2F-binding sites were predicted on all 23 human MMP gene promoters, many of which harbored multiple E2F-binding sites. Studies presented here show that MMP genes such as MMP9, MMP14, and MMP15 which are overexpressed in non-small cell lung cancer, have multiple E2F-binding sites and are regulated by the Rb-E2F pathway. Chromatin immunoprecipitation assays showed the association of E2F1 with the MMP9, MMP14, and MMP15 promoters, and transient transfection experiments showed that these promoters are E2F responsive. Correspondingly, depletion of E2F family members by RNA interference techniques reduced the expression of these genes with a corresponding reduction in collagen degradation activity. Furthermore, activating Rb by inhibiting the interaction of Raf-1 with Rb by using the Rb-Raf-1 disruptor RRD-251 was sufficient to inhibit MMP transcription. This led to reduced invasion and migration of cancer cells in vitro and metastatic foci development in a tail vein lung metastasis model in mice. These results suggest that E2F transcription factors may play a role in promoting metastasis through regulation of MMP genes and that targeting the Rb-Raf-1 interaction is a promising approach for the treatment of metastatic disease.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/22086850
      14. Call Number :
        PKI @ kd.modi @ 1
      15. Serial :
        10525
      1. Author :
        Kadioglu, A.; Brewin, H.; Hartel, T.; Brittan, J. L.; Klein, M.; Hammerschmidt, S.; Jenkinson, H. F.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2010
      5. Publication :
        Mol Oral Microbiol
      6. Products :
      7. Volume :
        25
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Xen10, Xen 10, Streptococcus pneumoniae Xen10, IVIS, Animals; Bacterial Adhesion; Bacterial Processes; Bacterial Proteins/*physiology; *Carrier State; Colony Count, Microbial; Female; Host-Pathogen Interactions; Lung/microbiology; Meningitis, Pneumococcal/microbiology; Mice; Models, Animal; Mutation; Nasopharynx/*microbiology; Pneumonia, Pneumococcal/complications; Sepsis/*microbiology; Streptococcus pneumoniae/*pathogenicity; Virulence Factors/physiology
      12. Abstract :
        Summary The pneumococcal cell surface protein PavA is a virulence factor associated with adherence and invasion in vitro. In this study we show in vivo that PavA is necessary for Streptococcus pneumoniae D39 colonization of the murine upper respiratory tract in a long-term carriage model, with PavA-deficient pneumococci being quickly cleared from nasopharyngeal tissue. In a pneumonia model, pavA mutants were not cleared from the lungs of infected mice and persisted to cause chronic infection, whereas wild-type pneumococci caused systemic infection. Hence, under the experimental conditions, PavA-deficient pneumococci appeared to be unable to seed from lung tissue into blood, although they survived in blood when administered intravenously. In a meningitis model of infection, levels of PavA-deficient pneumococci in blood and brain following intercisternal injection were significantly lower than wild type. Taken collectively these results suggest that PavA is involved in successful colonization of mucosal surfaces and in translocation of pneumococci across host barriers. Pneumococcal sepsis is a major cause of mortality worldwide so identification of factors such as PavA that are necessary for carriage and for translocation from tissue to blood is of clinical and therapeutic importance.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/20331793
      14. Call Number :
        PKI @ kd.modi @ 1
      15. Serial :
        10400
      1. Author :
        Kadurugamuwa, J. L.; Francis, K. P.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2008
      5. Publication :
        Methods in Molecular Biology
      6. Products :
      7. Volume :
        431
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Bioware, Xen29, Animals, Bacteria/chemistry/ genetics, Bacterial Infections/diagnosis/ microbiology, Biofilms/ growth & development, Diagnostic Imaging/methods, Luminescent Measurements/ methods IVIS, Xenogen, Xen5, Xen44
      12. Abstract :
        Whole body biophotonic imaging (BPI) is a technique that has contributed significantly to the way researchers study bacterial pathogens and develop pre-clinical treatments to combat their ensuing infections in vivo. Not only does this approach allow disease profiles and drug efficacy studies to be conducted non-destructively in live animals over the entire course of the disease, but in many cases, it enables investigators to observe disease profiles that could otherwise easily be missed using conventional methodologies. The principles of this technique are that bacterial pathogens engineered to express bioluminescence (visible light) can be readily monitored from outside of the living animal using specialized low-light imaging equipment, enabling their movement, expansion and treatment to be seen completely non-invasively. Moreover, because the same group of animals can be imaged at each time-point throughout the study, the overall number of animals used is dramatically reduced, saving lives, time, and money. Also, as each animal acts as its own control over time, the issues associated with animal-to-animal variation are circumvented, thus improving the quality of the biostatistical data generated. The ability to monitor infections in vivo in a longitudinal fashion is especially appealing to assess chronic infections such as those involving implanted devices. Typically, bacteria grow as biofilms on these foreign bodies and are reputably difficult to monitor with conventional methods. Because of the non-destructive and non-invasive nature of BPI, the procedure can be performed repeatedly in the same animal, allowing the biofilm to be studied in situ without detachment or disturbance. This ability not only allows unique patterns of disease relapse to be seen following termination of antibiotic therapy but also in vivo resistance development during prolonged treatment, both of which are common occurrences with device-related infections. This chapter describes the bioluminescent engineering of both Gram-positive and Gram-negative bacteria and overviews their use in device-associated infections in several anatomical sites in a variety of animal models.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/18287760
      14. Call Number :
        139321
      15. Serial :
        5568
      1. Author :
        Kadurugamuwa, J. L.; Modi, K.; Coquoz, O.; Rice, B.; Smith, S.; Contag, P. R.; Purchio, T.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2005
      5. Publication :
        Infection and Immunity
      6. Products :
      7. Volume :
        73
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        IVIS, Xenogen, Xen10
      12. Abstract :
        We developed a method for simultaneous in vivo biophotonic monitoring of pneumococcal meningitis and the accompanying neuronal injury in live transgenic mice. Streptococcus pneumoniae engineered for bioluminescence (lux) was used for direct visualization of disease progression and antibiotic treatment in a mouse model of meningitis. The host response was monitored in transgenic mice containing an inducible firefly luciferase (luc) reporter gene under transcriptional control of the mouse glial fibrillary acidic protein (GFAP) promoter. Based on the different spectra of light emission and substrate requirements for lux and luc, we were able to separately monitor the two reporters using a highly sensitive in vivo imaging system. The level of neuronal damage and recovery following antibiotic treatment was dependent on the time of treatment. This model has potential for simultaneous multiparameter monitoring and testing of therapies that target the pathogen or host response to prevent neuronal injury and recovery.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/16299273
      14. Call Number :
        139327
      15. Serial :
        7497
      1. Author :
        Kadurugamuwa, J. L.; Modi, K.; Yu, J.; Francis, K. P.; Orihuela, C.; Tuomanen, E.; Purchio, A. F.; Contag, P. R.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2005
      5. Publication :
        Mol Imaging
      6. Products :
      7. Volume :
        4
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Animals, Diagnostic Imaging, Disease Models, Animal, Female, Luminescent Measurements/methods, Meningitis, Pneumococcal/drug therapy/microbiology/ radiography, Mice, Mice, Inbred BALB C, Streptococcus pneumoniae/drug effects IVIS, Xenogen, Xen10
      12. Abstract :
        Noninvasive real-time in vivo bioluminescent imaging was used to assess the spread of Streptococcus pneumoniae throughout the spinal cord and brain during the acute stages of bacterial meningitis. A mouse model was established by lumbar (LP) or intracisternal (IC) injection of bioluminescent S. pneumoniae into the subarachnoid space. Bacteria replicated initially at the site of inoculation and spread progressively from the spinal cord to the brain or from the brain down to the cervical part of the spinal column and to the lower vertebral levels. After 24 hr, animals showed strong bioluminescent signals throughout the spinal canal, indicating acute meningitis of the intracranial and intraspinal meninges. A decline in bacterial cell viability, as judged by a reduction in the bioluminescent signal, was observed over time in animals treated with ceftriaxone, but not in untreated groups. Mice treated with the antibiotic survived infection, whereas all mice in untreated groups became moribund, first in the IC group then in the LP group. No untreated animal survived beyond 48 hr after induction of infection. Colony counts of infected cerebrospinal fluid (CSF) correlated positively with bioluminescent signals. This methodology is especially appealing because it allows detecting infected mice as early as 3 hr after inoculation, provide temporal, sequential, and spatial distribution of bacteria within the brain and spinal cord throughout the entire disease process and the rapid monitoring of treatment efficacy in a nondestructive manner. Moreover, it avoids the need to sacrifice the animals for CSF sampling and the potential manipulative damage that can occur with other conventional methods.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/16105511
      14. Call Number :
        139330
      15. Serial :
        7143
      1. Author :
        Kadurugamuwa, J. L.; Modi, K.; Yu, J.; Francis, K. P.; Purchio, T.; Contag, P. R.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2005
      5. Publication :
        Infection and Immunity
      6. Products :
      7. Volume :
        73
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Animals, Diagnostic Imaging/ methods, Female, Mice, Microscopy, Electron, Scanning, Photons, Proteus Infections/ diagnosis, Proteus mirabilis/drug effects/isolation & purification, Pseudomonas Infections/ diagnosis, Pseudomonas aeruginosa/drug effects/isolation & purification, Urinary Catheterization/ adverse effects, Urinary Tract Infections/ diagnosis IVIS, Xenogen, Xen5, Xen44
      12. Abstract :
        Urinary tract infections (UTIs) are among the most common bacterial infections acquired by humans, particularly in catheterized patients. A major problem with catheterization is the formation of bacterial biofilms on catheter material and the risk of developing persistent UTIs that are difficult to monitor and eradicate. To better understand the course of UTIs and allow more accurate studies of in vivo antibiotic efficacy, we developed a catheter-based biofilm infection model with mice, using bioluminescently engineered bacteria. Two important urinary tract pathogens, Pseudomonas aeruginosa and Proteus mirabilis, were made bioluminescent by stable insertion of a complete lux operon. Segments of catheter material (precolonized or postimplant infected) with either pathogen were placed transurethrally in the lumen of the bladder by using a metal stylet without surgical manipulation. The bioluminescent strains were sufficiently bright to be readily monitored from the outside of infected animals, using a low-light optical imaging system, including the ability to trace the ascending pattern of light-emitting bacteria through ureters to the kidneys. Placement of the catheter in the bladder not only resulted in the development of strong cystitis that persisted significantly longer than in mice challenged with bacterial suspensions alone but also required prolonged antibiotic treatment to reduce the level of infection. Treatment of infected mice for 4 days with ciprofloxacin at 30 mg/kg of body weight twice a day cured cystitis and renal infection in noncatheterized mice. Similarly, ciprofloxacin reduced the bacterial burden to undetectable levels in catheterized mice but did not inhibit rebound of the infection upon cessation of antibiotic therapy. This methodology easily allows spatial information to be monitored sequentially throughout the entire disease process, including ascending UTI, treatment efficacy, and relapse, all without exogenous sampling, which is not possible with conventional methods.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/15972473
      14. Call Number :
        139333
      15. Serial :
        7110
      1. Author :
        Kadurugamuwa, J. L.; Sin, L. V.; Yu, J.; Francis, K. P.; Kimura, R.; Purchio, T.; Contag, P. R.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2003
      5. Publication :
        Antimicrobial Agents and Chemotherapy
      6. Products :
      7. Volume :
        47
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Animals, Anti-Bacterial Agents/ pharmacology, Bacterial Infections/drug therapy/microbiology, Biofilms/ drug effects/growth & development, Bioware; Catheterization/adverse effects, Chemiluminescent Measurements, Ciprofloxacin/pharmacology, Colony Count, Microbial, Disease Models, Animal, Dose-Response Relationship, Drug, Drug Monitoring/methods, Mice, Rifampin/pharmacology, Staphylococcus aureus/drug effects/genetics/growth & development, Tobramycin/pharmacology IVIS, Xenogen; Xen29
      12. Abstract :
        We have developed a rapid, continuous method for monitoring the effectiveness of several antibacterial agents in real time, noninvasively, by using a recently described mouse model of chronic biofilm infection (J. L. Kadurugamuwa et al., Infect. Immun. 71:882-890, 2003), which relies on biophotonic imaging of bioluminescent bacteria. To facilitate real-time monitoring of infection, we used a Staphylococcus aureus isolate that was made bioluminescent by inserting a modified lux operon into the bacterial chromosome. This bioluminescent reporter bacterium was used to study the antimicrobial effects of several antibiotics belonging to different molecular families. Treatment with rifampin, tobramycin, and ciprofloxacin was started 7 days after subcutaneous implantation of catheters precolonized with 10(4) CFU of S. aureus. Three different doses of antibiotics were administered twice a day for 4 consecutive days. The number of metabolically active bacteria in untreated mice and the tobramycin- and ciprofloxacin-treated groups remained relatively unchanged over the 4-week observation period, indicating poor efficacies for tobramycin and ciprofloxacin. A rapid dose-dependent decline in metabolic activity in rifampin-treated groups was observed, with almost a 90% reduction after two doses and nearly undetectable levels after three doses. The disappearance of light emission correlated with colony counts. After the final treatment, cell numbers rebounded as a function of concentration in a time-dependent manner. The staphylococci isolated from the catheters of mice treated with rifampin were uniformly resistant to rifampin but retained their in vitro susceptibilities to tobramycin and ciprofloxacin. Since the metabolic activities of viable cells and a postantibiotic effect could be detected directly on the support matrix nondestructively and noninvasively, the methodology is specifically appealing for investigating the effects of antibiotics on biofilms in vivo. Moreover, our study points to the possible use of biophotonic imaging for the detection of the development of resistance to therapeutic agents during treatment of chronic infections in vivo.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/14506020
      14. Call Number :
        139345
      15. Serial :
        7448
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