ABSTRACT
Objective To investigate the antimicrobial susceptibility of 97 clinical Staphylococcus aureus (S. aureus) strains against 14 antimicrobials and corresponding resistance mechanisms. Methods The antimicrobial susceptibility of the isolates was determined using a disk diffusion method and antimicrobial resistance genes were screened by polymerase chain reaction. Mutations responsible for ciprofloxacin and rifampicin resistance were investigated by polymerase chain reaction and DNA sequencing. Results All isolates were found to be susceptible to vancomycin. Various rates of resistance to penicillin (83.5%), ampicillin (77.3%), erythromycin (63.9%), tetracycline (16.5%), amoxicillin/clavulanic acid (16.5%), ciprofloxacin (15.5%), trimethoprim/sulfamethoxazole (15.5%), oxacillin (13.4%), fusidic acid (12.4%), rifampin (6.2%), clindamycin (6.2%), gentamicin (6.2%) and mupirocin (5.2%) were determined. In addition, different combinations of resistance genes were identified among resistant isolates. Ciprofloxacin resistant isolates had mutations in codon 84 (Ser84Leu) and 106 (Gly106Asp) in the gyrA gene. Mutations in grlA were mostly related to Ser80Phe substitution. Leu466Ser mutation in the rpoB gene was detected in all rifampin resistant isolates. All methicillin resistant S. aureus isolates were SCCmec type V. Conclusions In conclusion, it was determined that the isolates were resistant to different classes of antimicrobials at varying rates and resistance was mediated by different genetic mechanisms. Therefore, continuous monitoring of resistance in S. aureus strains is necessary to control their resistance for clinically important antimicrobials.
ABSTRACT
OBJECTIVE@#To investigate the antimicrobial susceptibility of 97 clinical Staphylococcus aureus (S. aureus) strains against 14 antimicrobials and corresponding resistance mechanisms.@*METHODS@#The antimicrobial susceptibility of the isolates was determined using a disk diffusion method and antimicrobial resistance genes were screened by polymerase chain reaction. Mutations responsible for ciprofloxacin and rifampicin resistance were investigated by polymerase chain reaction and DNA sequencing.@*RESULTS@#All isolates were found to be susceptible to vancomycin. Various rates of resistance to penicillin (83.5%), ampicillin (77.3%), erythromycin (63.9%), tetracycline (16.5%), amoxicillin/clavulanic acid (16.5%), ciprofloxacin (15.5%), trimethoprim/sulfamethoxazole (15.5%), oxacillin (13.4%), fusidic acid (12.4%), rifampin (6.2%), clindamycin (6.2%), gentamicin (6.2%) and mupirocin (5.2%) were determined. In addition, different combinations of resistance genes were identified among resistant isolates. Ciprofloxacin resistant isolates had mutations in codon 84 (Ser84Leu) and 106 (Gly106Asp) in the gyrA gene. Mutations in grlA were mostly related to Ser80Phe substitution. Leu466Ser mutation in the rpoB gene was detected in all rifampin resistant isolates. All methicillin resistant S. aureus isolates were SCCmec type V.@*CONCLUSIONS@#In conclusion, it was determined that the isolates were resistant to different classes of antimicrobials at varying rates and resistance was mediated by different genetic mechanisms. Therefore, continuous monitoring of resistance in S. aureus strains is necessary to control their resistance for clinically important antimicrobials.
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Aim of the study: To investigate the effects of dose-volume parameters of brain parenchyma, optic nerves [ONs] and cribriform plate [CP], which were determined on central nervous system [CMS] control in pediatric leukemia patients who have undergone prophylactic cranial irradiation [PCI] at our department
Patients and Methods: In the current study, the records of 14 patients were examined retrospectively. Along with the minimum and maximum doses for brain and CP, D95% [minimal dose received by the 95% volume of a structure] and V95% [percent volume of target receiving 95% of prescribed dose] could be obtained from the dose-volume histogram. Statistical analyses were conducted using the Mann Whitney test in SPSS-15
Results: ALL/AMI ratio was 9/5. CMS relapse was observed only in 2 patients. The minimum dose was 1249 [1100-1782] cGy, 1036 [547-1651] cGy, 856 [308-1460] cGy and 1234 [922-1727] cGy for brain parenchyma, right ON, left ON and CP, respectively. The value of D95%/D was 1,01 [1-1.06] and 0.99 [0.92-1.06] for brain parenchyma and CP, respectively. V95% was 99.8% [98.6%-100%] and 98.1% [80.5%-100%] for brain parenchyma and CP, respectively. The analyses revealed that none of the target tissue dose-volume parameters for PCI affected CNS relapse [p>0.05]
Conclusion: In our study; it was found that the dose-volume parameters of the brain, CP and ONs did not have any effect on CNS relapse. Along with the other clinical factors, the scarce number of patients included in the study might have concealed the effects of parameters related to RT.
Subject(s)
Child , Female , Humans , Male , Treatment Outcome , Radiotherapy Planning, Computer-Assisted , Dose-Response Relationship, Radiation , Leukemia/radiotherapy , Child , Retrospective StudiesABSTRACT
OBJECTIVE@#To determine biofilm and hydrophobicity formation ratios in extended spectrum beta lactamases (ESBL) synthesizing Escherichia coli isolates which were isolated from feces samples of 150 cage bird species randomly taken from pet shops in Hatay province, Turkey.@*METHODS@#In vitro biofilm production of 4 ESBL positive isolates were performed by Congo Red Agar (CRA), Standard Tube (ST) and Microtitre Plate (MP) methods while their hydrophobicity were examined by bacterial adhesion to hydrocarbon (BATH) test.@*RESULTS@#In the examined isolates, while biofilm production was found to be negative by CRA method, highest biofilm producing strain, among 4 bacteria was determined to be A42 by ST and MP methods. The Scanning Electron Microscopy (SEM) also displayed these confirmed findings. The hydrophobicity values of strains were determined to be between 22.45% and 26.42%.@*CONCLUSIONS@#As a result, biofilm formation in cage bird feces originated ESBL positive Escherichia coli isolates was performed for the first time in Turkey. In order to present the relation between pathogenicity and biofilm production in animal originated ESBL positive isolates, further studies are required.
ABSTRACT
Objective To determine biofilm and hydrophobicity formation ratios in extended spectrum beta lactamases (ESBL) synthesizing Escherichia coli isolates which were isolated from feces samples of 150 cage bird species randomly taken from pet shops in Hatay province, Turkey. Methods In vitro biofilm production of 4 ESBL positive isolates were performed by Congo Red Agar (CRA), Standard Tube (ST) and Microtitre Plate (MP) methods while their hydrophobicity were examined by bacterial adhesion to hydrocarbon (BATH) test. Results In the examined isolates, while biofilm production was found to be negative by CRA method, highest biofilm producing strain, among 4 bacteria was determined to be A42 by ST and MP methods. The Scanning Electron Microscopy (SEM) also displayed these confirmed findings. The hydrophobicity values of strains were determined to be between 22.45% and 26.42%. Conclusions As a result, biofilm formation in cage bird feces originated ESBL positive Escherichia coli isolates was performed for the first time in Turkey. In order to present the relation between pathogenicity and biofilm production in animal originated ESBL positive isolates, further studies are required.