Effect of sub-lethal challenge with Photodynamic Antimicrobial Chemotherapy (PACT) on the antibiotic susceptibility of clinical bacterial isolates
Data(s) |
01/04/2010
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Resumo |
This study aimed to determine the effect of sub-lethal challenge with Photodynamic Antimicrobial Chemotherapy (PACT) on the susceptibility of clinical Staphylococcus aureus and Pseudomonas aeruginosa isolates to both PACT and a range of antibiotics used in the treatment of infection caused by these bacteria. Clinical S. aureus and P. aeruginosa isolates were exposed to sub-lethal PACT with meso-tetra (N-methyl-4-pyridyl) porphine tetra tosylate (TMP) and methylene blue (MB) over a 72 h period. After exposure, susceptibility of surviving organisms to a range of antibiotics was determined and compared with the susceptibility of an untreated control. Surviving bacteria were also exposed to previously lethal photosensitizer-light combinations, to determine if susceptibility to PACT was affected by sub-lethal exposure. Exposure to sub-lethal PACT did not decrease susceptibility to antibiotics with the minimum inhibitory concentrations for 95% and 100% of P. aeruginosa and S. aureus isolates, respectively, within two doubling dilutions of the MIC of the untreated control. Similarly, habituation with sub-lethal PACT did not reduce susceptibility of P. aeruginosa isolates to PACT levels previously determined as lethal. A reduction in susceptibility to PACT following habituation was apparent for two S. aureus isolates with MB and for 1 S. aureus isolate with IMP. However, for two of these three isolates, the log reduction for habituated cells was still greater than 4 log(10). PACT remains an attractive potential treatment for infection caused by these bacteria. (C) 2010 Elsevier B.V. All rights reserved. |
Identificador |
http://dx.doi.org/10.1016/j.jphotobiol.2010.02.004 http://www.scopus.com/inward/record.url?scp=77952240183&partnerID=8YFLogxK |
Idioma(s) |
eng |
Direitos |
info:eu-repo/semantics/restrictedAccess |
Fonte |
Cassidy , C M , Donnelly , R & Tunney , M 2010 , ' Effect of sub-lethal challenge with Photodynamic Antimicrobial Chemotherapy (PACT) on the antibiotic susceptibility of clinical bacterial isolates ' JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY , vol 99 , no. 1 , pp. 62-66 . DOI: 10.1016/j.jphotobiol.2010.02.004 |
Palavras-Chave | #/dk/atira/pure/subjectarea/asjc/1300/1304 #Biophysics #/dk/atira/pure/subjectarea/asjc/2700/2741 #Radiology Nuclear Medicine and imaging #/dk/atira/pure/subjectarea/asjc/3100/3108 #Radiation #/dk/atira/pure/subjectarea/asjc/3600/3614 #Radiological and Ultrasound Technology |
Tipo |
article |