The present study involved a qualitative and quantitative evaluation of tongue dorsum biofilms sampled from halitosis patients and healthy volunteers. The aim of the study was to quantify the distribution of Streptococcus spp. and Fusobacterium nucleatum within the oral halitosis biofilm in order to highlight the role of these bacterial members in halitosis. Tongue plaque samples from four halitosis-diagnosed patients and four healthy volunteers were analyzed and compared. The visualization and quantification of the tongue dorsum biofilm was performed combining fluorescence in situ hybridization (FISH) and confocal laser scanning microscopy (CLSM). Eubacteria, Streptococcus spp. and Fusobacterium nucleatum were stained using specific fluorescent probes. For a comparison of the two tested biofilm groups the Wilcoxon rank-sum test was used. Morphological analysis by CLSM illustrated the distribution of the species which were tracked. Streptococcus spp. appeared to be enclosed within the samples and always associated to F. nucleatum. Furthermore, compared to the control group the biofilm within the halitosis group contained significantly higher proportions of F. nucleatum and Streptococcus spp., as revealed by the FISH and CLSM-analysis. The total microbial load and relative proportions of F. nucleatum and Streptococcus spp. can be considered as causative factors of halitosis and thus, as potential treatment targets.
Clonality and Antimicrobial Susceptibility of Burkholderia cepacia complex Isolates Collected from Cystic Fibrosis Patients during 1998-2013 in Bern, Switzerland.
For the first time, we analyzed the clonality and susceptibility of Burkholderia cepacia complex isolates (n=55) collected during 1998-2013 from 44 Swiss cystic fibrosis (CF)-patients. B. cenocepacia (n=28) and B. multivorans (n=14) were mainly of sequence type (ST) 833 and ST874, respectively; B. contaminans isolates were of ST102. Overall, the following MIC50/90s (mg/l) were obtained: piperacillin/tazobactam (≤ 4/≥ 128), ticarcillin/clavulanate (≥ 256/≥256), ceftazidime (2/≥ 32), aztreonam (16/≥ 32), meropenem (2/8), tobramycin (8/≥ 16), minocycline (≤ 1/16), levofloxacin (≤ 0.5/≥ 16), and trimethoprim/sulfamethoxazole (≤ 0.5/4). This is the first survey providing information on the clonality of Bcc detected in Switzerland. Species identification and antimicrobial susceptibility tests should always be routinely performed to adapt more targeted therapies.
- New Microbiologica
- Citations: 12
- Apr 1, 2015
In vitro activity of clinically implemented β-lactams against Aerococcus urinae: presence of non-susceptible isolates in Switzerland.
We analyzed the in vitro susceptibility to several ?-lactams and vancomycin of 80 Aerococcus urinae isolates collected during 2011-2012 in Switzerland. MICs were determined by Etest (bioMérieux) on Müller-Hinton agar with 5% sheep blood and interpreted according to the CLSI and EUCAST criteria set for viridans streptococci. MIC50/90 for penicillin, amoxicillin, ceftriaxone and vancomycin were 0.016/0.064 mg/l, 0.032/0.064 mg/l, 0.125/0.5 mg/l and 0.38/0.5 mg/l, respectively. Three (3.8%) isolates were resistant to ceftriaxone regardless of the criteria used (MICs ?2 mg/l); one of them was also non-susceptible to penicillin (MIC of 0.25 mg/l) according to CLSI. β-lactam resistance in A. urinae is a concern and suggests that more studies are needed to determine the molecular mechanisms of such resistance.
- New Microbiologica
- Citations: 8
- Oct 1, 2014
Beijing/W and major spoligotype families of Mycobacterium tuberculosis strains isolated from tuberculosis patients in Eastern Turkey.
The aim of this study was to determine the Beijing/W family and major phylogenetic clades of Mycobacterium tuberculosis strains of tuberculosis patients in a city with a tuberculosis incidence higher than the country average. A total of 220 M. tuberculosis strains isolated over a period of more than four years were typed by spoligotyping. Spoligotyping resulted in 64 different patterns, 38 (17.3%) of which were unique, and 26 were clusters including 182 (82.7%) strains. The major shared types were ST 53 (n = 55, 25%), ST 41 (LAM7-TUR; n = 19, 8.6%), and ST 284 (n = 15, 6.8%). The major clades observed ranked in the following order: ill-defined T superfamily (n = 112, 50.9%); Latino-American-Mediterranean (LAM; n = 33, 15%); Haarlem (n = 24, 10.9%); and the S family (n = 9, 4.1%). Three strains were in the Beijing family. A high number of strains (33 strains) showed patterns that did not fall within any of the major clades described. M. tuberculosis strains in Malatya have both STs showing a widespread distribution over the world and those restricted to this city, confirming the highly diverse nature of tuberculosis. Our results suggest that the Beijing clade, which is more prevalent among the strains with MDR and isoniazid resistance, is currently not a problem in Eastern Turkey.
- New Microbiologica
- Citations: 9
- Jul 1, 2009