All assays

were performed four times. Mean values of the four repetitions, standard deviations, and CV were calculated and the mean value was considered the value which was then used to categorize the isolates as “R”, “I” or “S”. The susceptibility profile of mucoid and non-mucoid isolates was evaluated under the different conditions performed in this study (MIC, BIC and MCA). Statistical analysis The Wilcoxon signed ranks test was used for statistical analysis of quantitative values of MIC and BIC. McNemar-Bowker test was used to evaluate the categories MK-8776 of the results obtained (“S”, “I” and “R”) by the standard technique and the technique in biofilm. P < 0.05 indicated statistical S3I-201 significance.

Ethics aspects The bacterial isolates were obtained from clinical specimens sent for routine culture in the Microbiology Unit of Hospital de Clínicas de Porto Alegre. The information was compiled in order to respect the privacy of patients; written informed consent for participation in the study was obtained from participants or, where participants were children, from a parent or guardian. This study was approved by the Ethics Committee in Research of Hospital de Clínicas de Porto Alegre (project number 06 – 406). Acknowledgements We would like to thank Vania Naomi Hirakata for assistance Bay 11-7085 with statistical analyses. Funding This work received financial support from FIPE (Fundo de Incentivo à Ensino e Pesquisa do Hospital de Clínicas de Porto Alegre), CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico) and ANVISA (Agência Nacional de Vigilância Sanitária). MG132 References 1. Staab D: Cystic fibrosis – therapeutic challenge in cystic fibrosis children. Eur J Endocrinol 2004,151(Suppl 1):S77-S80.PubMedCrossRef 2. Baltimore RS, Christie CD, Smith GJ:

Immunohistopathologic localization of Pseudomonas aeruginosa in lungs from patients with cystic fibrosis. Implications for the pathogenesis of progressive lung deterioration. Am Rev Respir Dis 1989, 140:1650–1661.PubMedCrossRef 3. Costerton JW, Cheng KJ, Geesey GG, Ladd TI, Nickel JC, Dasgupta M, Marrie TJ: Bacterial biofilms in nature and disease. Annu Rev Microbiol 1987, 41:435–464.PubMedCrossRef 4. Drenkard E, Ausubel FM: Pseudomonas biofilm formation and antibiotic resistance are linked to phenotypic variation. Nature 2002, 416:740–743.PubMedCrossRef 5. Singh PK, Schaefer AL, Parsek MR, Moninger TO, Welsh MJ, Greenberg EP: Quorum-sensing signals indicate that cystic fibrosis lungs are infected with bacterial biofilms. Nature 2000, 407:762–764.PubMedCrossRef 6. Hacth RA, Schiller NL: Alginate lyase promotes diffusion of aminoglycosides through the extracellular polysaccharide of mucoid Pseudomonas aeruginosa .