Molecular epidemiology of penicillin resistantStreptococcus pneumoniae strains in Turkey. A multicenter study

A total of 539 isolates recovered from various clinical sites were collected from 13 hospitals from different regions of Turkey between 1999 and 2002. Susceptibility to penicillin and cefotaxime was determined by the E-test and the remaining antimicrobials were evaluated by disk diffusion tests. Penicillin resistant and intermediate isolates were serotyped and PFGE patterns were analysed. Overall 16 isolates (3%) were resistant to penicillin, and 143 (26.5%) were intermediate. Resistance and intermediate rates were 3.1% and 29.0% respectively in respiratory tract isolates. Multiple resistance (resistance to ≥3 antibiotics) occurred in 81.8% of the penicillin resistant isolates and the most frequent resistance phenotype was penicillin+trimethoprim/sulphamethoxazole (37.7%). Minimum inhibitory concentrations of cefotaxime were lower than 1 mg/ml for all the isolates. The highest rate of resistance was observed for trimethoprim/ sulphamethoxazole (26.6%) followed by doxycycline (12.6%). Resistance to erythromycin was 10.1%, clindamycin 9.9%, chloramphenicol 4.3%, ofloxacin 5.0% and levofloxacin 0.2%. There was no resistance to vancomycin. Resistant isolates belonged to serogroups 9, 23, and 6. The most frequent serogroups among intermediate isolates were 23, 19, 14, 1, 9, and 6. Five distinct PFGE patterns were observed among penicillin resistant isolates. There was no distinct clustering of specific PFGE patterns in the study centres. No correlation between serotypes, resistance and PFGE patterns was found. There seems to be genetic heterogeneity inStreptococccus pneumoniae isolates in Turkey.     

Pharmaceuticals from cultured algae

Summary An algae screening program, including cultured macroalgae, cultured cyanobacteria and cultured eukaryotic microalgae has been undertaken. Methods for the isolation, purification, preservation and cultivation of axenic cyanobacteria and eukaryotic cultures have been developed. Screening of these groups for biologically active components has lead to the isolation of pachydictyol and caulerpenyne from cultured macroalgae, while a series of hapalindoles and an antifungal depsipeptide have been isolated from cyanobacteria.     

Legacies of invasive plant management: effects of leaching from glyphosate-treated and untreated plants on germination and early growth of native macrophytes

Biological Invasions - Invasive plant management can support the restoration of native plant communities. Glyphosate-based herbicides are commonly used for management because glyphosate does not...     

Quicolor: A novel system for rapid antibacterial susceptibility testing

Early determination of antibacterial susceptibility increases the success of therapy, decreases unnecessary use of antibacterials and side effects and lowers the overall healthcare costs. We have evaluated a rapid antibacterial susceptibility test, Quicolor (Salubris Inc., Massachusetts, USA), which is based on a rapid culture medium that indicates growth early by changing its colour. Quicolor proved to be a reliable rapid test for determining antibacterial susceptibility, having an overall agreement of 97.6% with the conventional CLSI sisk diffusion susceptibility test results. Between two methods overall agreement was 96.7% for Enterobacteriaceae, 96.8% for staphylococci and 94.2% for non-fermentative bacteria. There was only 0.6% major discrepancy in Enterobacteriaceae, 1.7% in staphylococci and 0.9% in non-fermentative bacteria. Since the test provides results in 3.5–6 h, it can provide the means to choose the right treatment regimen the same day the infectious agent is isolated.     

The diagnosis of malaria and identification of plasmodium species by polymerase chain reaction in Turkey

More than half of the world's population is exposed to malaria in approximately 100 countries. Rapid diagnosis and correct treatment of cases are the main objectives of control programs in malaria endemic areas. We have developed a PCR method to determine the presence of plasmodium DNA in blood. The method can also identify the species of the plasmodium by restriction enzyme analysis of the amplified product. We evaluated the performance of this method in the diagnosis of malaria suspected cases in Turkey by comparing to microscopy of the blood smears: blood samples were obtained from 114 patients with malaria symptoms, including fever and/or chills lasting for several days, before starting treatment. Thin and thick blood smears were prepared immediately in the region of specimen collection. After isolation of DNA from blood samples, DNA was amplified by PCR and digested by restriction enzyme AluI. The obtained fragments were analyzed by agarose gel electrophoresis. The number of parasites in the thick and thin smears of the blood samples was evaluated microscopically after staining by Giemsa and results were compared by PCR results. Among 114 plasmodium positive cases detected by microscopy, 100 were also detected by PCR. There were 14 false negatives and no false positive by PCR. Compared to microscopy, the sensitivity, specificity and Positive Predictive Value (PPV) of PCR were determined as 76%, 100% and 100%, respectively.     

Rapid detection of methicillin resistance in <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> isolates; evaluation of colorimetric Quicolor ES agar and determination of breakpoint inhibition zone diameters of cefoxitin

In this study, it was aimed to evaluate colorimetric Quicolor ES agar for the rapid detection of methicillin resistance and to determine susceptibility and resistance breakpoint zone diameters for cefoxitin by using 51 methicillin susceptible Staphylococcus aureus (MSSA) and 63 methicillin resistant S. aureus (MRSA) isolates. In the study, while oxacillin and cefoxitin results were obtained within 4–7 h (5.5 h in average) for MSSA isolates, the results of MRSA isolates were obtained within 5.5–9 h (6.6 h in average) for both antibiotics on QC ES agar. QC ES agar is an inexpensive medium for rapid detection (4–9 h) of methicillin resistance by disc diffusion method using oxacillin or cefoxitin. Additional studies for further evaluation of the efficiency of QC-ES agar in rapid determination of methicillin resistance in S. aureus may be beneficial.