Results from the Survey of Antibiotic Resistance (SOAR) 2002-09 in Turkey.

OBJECTIVES: To investigate changes in antibiotic susceptibility of Streptococcus pneumoniae and Haemophilus influenzae from the Survey of Antibiotic Resistance (SOAR) in community-acquired respiratory tract infections (CA-RTIs) between 2002 and 2009 in Turkey. METHODS: Previously published SOAR data were used for this analysis. MICs were determined using Etest(®) gradient strips or disc diffusion. Susceptibility against a range of antimicrobial agents was assessed using CLSI breakpoints. RESULTS: A total of 900 S. pneumoniae isolates were analysed: 2002-03 (n = 75), 2004-05 (n = 301) and 2007-09 (n = 524). Four antibiotics were tested consistently throughout and three showed a statistically significant decrease in susceptibility (P < 0.0001): penicillin (74.7% susceptible in 2002-03; 67.8% in 2004-05; and 47.2% in 2007-09); cefaclor (85.3% in 2002-03; 78.7% in 2004-05; and 53.5% in 2007-09) and clarithromycin (85.3% in 2002-03; 82.7% in 2004-05; and 61.9% in 2007-09). Susceptibility to amoxicillin/clavulanic acid did not significantly change (100% in 2002-03; 98.7% in 2004-05; and 97.7% in 2007-09). A total of 930 H. influenzae isolates were analysed: 2002-03 (n = 133), 2004-05 (n = 379) and 2007-09 (n = 418). Four antibiotics were also consistently tested: ampicillin, amoxicillin/clavulanic acid, clarithromycin and cefaclor. All showed >90% susceptibility, but only cefaclor susceptibility significantly reduced (P < 0.0001) over time (99.2% in 2002-03; 96.3% in 2004-05; and 90.4% in 2007-09). CONCLUSIONS: In S. pneumoniae from Turkey, there has been a clear statistically significant reduction in susceptibility to key antibiotics since 2002, but not to amoxicillin/clavulanic acid (or amoxicillin). However, susceptibility in H. influenzae remained stable. Continued surveillance is required to monitor future changes in antibiotic susceptibility for CA-RTI bacteria.

Antibiotic loaded nanocapsules functionalized with aptamer gates for targeted destruction of pathogens.

In this study, we designed aptamer-gated nanocapsules for the specific targeting of cargo to bacteria with controlled release of antibiotics based on aptamer-receptor interactions. Aptamer-gates caused a specific decrease in minimum inhibitory concentration (MIC) values of vancomycin for Staphylococcus aureus when mesoporous silica nanoparticles (MSNs) were used for bacteria-targeted delivery.

The examination of protective effects of gallic acid against damage of oxidative stress during induced-experimental renal ischemia-reperfusion in experiment.

AIM: In this study, probable effects of gallic acid were investigated in experimentally induced renal I/R injury in rats. MATERIAL AND METHODS: For this purpose, each group consisted of 7 Spraque dawley male albino rats. Groups were defined as follows; Group I: control group; Group II: I/R group; Group III, IV and V: I/R+Gallic acid (50, 100 and 200 mg.kg-1 respectively-i.p.). Left kidney was removed by nephrectomy except for Group I. I/R was induced in the other kidney. Gallic acid was given 15 mins before ischemia induction. SOD, CAT and Gpx activities were determined by electrophoresis. MDA, MPO levels were determined spectrophotometrically. Histopathological investigations were also performed in kidney tissues. BUN and Creatinine levels in serum were determined. RESULTS: BUN, Creatinine and MDA levels were statistically significant but MPO level was not statistically significantly increased in Group II. For SOD, CAT, Gpx activities in Group II, an increase was determined with respect to Group I. Histopathological investigations revealed widespread hyperemia in glomerulus, expansion of the structure between tubules and cell disruptions in Group II. In Group V (200 mg.kg-1 gallic acid), in terms of biochemical parameters, in spite of the significant decrease in BUN, Creatinine and MDA levels; a decrease was determined in SOD, CAT and Gpx isoenzyme activities. Group V showed histologically that I/R injury had been prevented to a greater extent and appearances were close to the control. CONCLUSION: As a result, in terms of our study, evaluations regarding kidney functions and histopathology have shown that gallic acid has protective effects in renal I/R injury (Tab. 2, Fig. 5, Ref. 36).

Molecular epidemiology and the clinical significance of Acinetobacter baumannii complex isolated from cerebrospinal fluid in neurosurgical intensive care unit patients.

OBJECTIVE: This study was intended to investigate the clinical significance and molecular epidemiology of Acinetobacter baumannii complex (ABC) isolated from cerebrospinal fluid (CSF) in neurosurgical intensive care unit (NSICU) patients, particularly comparing isolates from healthcare workers' (HCW) hands. METHODS: We retrospectively reviewed the medical records of 30 patients with CSF cultures positive for ABC seen at our NSICU from the date it first opened, January 2007, to September 2010. Pulsed-field gel electrophoresis (PFGE) typing was performed on 68 strains isolated from 32 patients' CSF and 36 HCWs' hands. RESULTS: ABC isolates were considered to be clinically significant in 21 (70.0%) patients but insignificant in the other nine (30.0%) patients. The prolonged (>7 days) use of cephalosporins was more common in patients with clinically significant ABC isolates (p = 0.049). Multiple drug resistance (MDR) was observed in 12 (57.1%) clinically significant isolates. Empirical antimicrobial therapies were not appropriate for nine of these 21 patients (42.8%). Mortality was significantly higher in the clinically significant group than in the clinically insignificant group (18/21 vs. 3/9; p = 0.008). Fifty-three isolates (77.9%) were grouped into 15 clusters, three of which contained possibly related isolates from patients' CSF and staff members' hands. CONCLUSIONS: The fact that ABC isolates grown from CSF cultures do not always exhibit infection and have high multiple antibiotic resistance, including to carbapenems, should be borne in mind when planning treatment for these patients. In addition, HCWs' hands may play a significant role in transmission to patients, and compliance with infection control procedures, especially hand washing, must be enhanced in order to avoid ABC infections.

Breakthrough Trichosporon asahii fungemia in neutropenic patient with acute leukemia while receiving caspofungin.

A 47-year-old man with newly diagnosed acute myeloblastic leukemia and non-insulin-dependent diabetes mellitus developed Trichosporon asahii fungemia while receiving caspofungin as empirical antifungal therapy. The diagnosis was based on repeated isolation of T. asahii in culture of blood for three times. Despite treatment with amphotericin B and voriconazole, the patient died. The in vitro antifungal susceptibilities of the T. asahii isolates were only available after the patient died. In vitro antifungal susceptibility tests showed high caspofungin and amphotericin B minimal inhibitory concentrations (MICs) value for this Trichosporon strain (MICs, 16 microg/ml, and>32 microg/ml, respectively). Fluconazole, itraconazole, and voriconazole exhibited low MICs in vitro (MICs, 4 microg/ml, 0.5 microg/ml, and

Procion Green H-4G immobilized poly(hydroxyethylmethacrylate/chitosan) composite membranes for heavy metal removal.

The effective removal of toxic heavy metals from environmental samples still remains a major topic of present research. Metal-chelating membranes are very promising materials as adsorbents when compared with conventional beads because they are not compressible, and they eliminate internal diffusion limitations. The purpose of this study was to evaluate the performance of a novel adsorbent, Procion Green H-4G immobilized poly(hydroxyethylmethacrylate (HEMA)/chitosan) composite membranes, for the removal of three toxic heavy metal ions, namely, Cd(II), Pb(II) and Hg(II) from aquatic systems. The Procion Green H-4G immobilized poly(hydroxyethylmethacrylate/chitosan) composite membranes were characterized by elemental analysis, scanning electron microscopy and Fourier transform infrared (FTIR) spectroscopy. The immobilized amount of the Procion Green H-4G was calculated as 0.018+/-0.003 micromol/cm(2) from the nitrogen and sulphur stoichiometry. The adsorption capacity of Procion Green H-4G immobilized poly(hydroxyethylmethacrylate/chitosan) composite membranes for selected heavy metal ions from aqueous media containing different amounts of these ions (30-400mg/l) and at different pH values (2.0-6.0) was investigated. The amount of Cd(II), Pb(II) and Hg(II) adsorbed onto the membranes measured at equilibrium, increased with time during the first 45 min and then remained unchanged toward the equilibrium adsorption. The maximum amounts of heavy metal ions adsorbed were 43.60+/-1.74, 68.81+/-2.75 and 48.22+/-1.92 mg/g for Cd(II), Pb(II) and Hg(II), respectively. The heavy metal ion adsorption on the pHEMA/chitosan membranes (carrying no dye) were relatively low, 6.31+/-0.13 mg/g for Cd(II), 18.73+/-0.37 mg/g for Pb(II) and 18.82+/-0.38 mg/g for Hg(II). Competitive adsorption of the metal ions was also studied. When the metal ions competed with each other, the adsorbed amounts were 12.74+/-0.38 mg Cd(II)/g, 28.80+/-0.86 mg Pb(II)/g and 18.41+/-0.54 mg Hg(II)/g. Procion Green H-4G immobilized poly(hydroxyethylmethacrylate/chitosan) membranes can be regenerated by washing with a solution of nitric acid (0.01 M). The percent desorption achieved was as high as 95%. These novel membranes are suitable for repeated use for more than five adsorption/desorption cycles without any considerable loss in adsorption capacity. Adsorption equilibria were well described by Langmuir equation. It can be concluded that Procion Green H-4G immobilized poly(hydroxyethylmethacrylate/chitosan) membranes may effectively be used for the removal of Cd(II), Pb(II) and Hg(II) ions from aqueous solutions.

The effect of pH on the corrosion of dental metal alloys.

The aim of this study was to determine the effects of the oral environment's pH on the corrosion of dental metals and alloys that have different compositions, using electrochemical methods. The corrosion rates and the cathodic Tafel slopes were obtained from the current-potential curves. The effect of pH on the corrosion of dental metals and alloys was dependent on their composition. Dissolution of the ions occurred in all of the tested pH states. The dissolution was moderately low for samples containing titanium because its surface was covered with a protective layer, whereas the dissolution was maximal for the samples containing tin and copper. Addition of cobalt and molybdenum to the alloys improved their corrosion resistance; these cobalt and molybdenum alloys were not effected by changes in the pH. Dissolution of the precious metal alloys increased as the percentage of noble metals increased. The corrosion characteristics of dental metals and alloys are important because the corrosion tendencies of dental alloys in the mouth may cause health hazards, weakening and the aesthetic loss of dental restorations.

Corrosion behaviour of dental metals and alloys in different media.

The corrosion tendencies of metals are related with their position in the electromotive series. These electrode potential degrees may change due to the compositions of the alloys, the surrounding media, or due to alterations in the composition because of recurrent casting. Therefore in this research, the electrode potentials and their changes over a period of time were measured in different pH media simulating the oral electrochemical conditions in vitro. The surface structure of the first and second castings of 29 different dental metals and alloys were examined under a scanning electron microscope and their composition in percentage weight was calculated by the Energy-dispersive X-ray Analysor system. Further the current-potential curves of the dental alloys were found by the potentiodynamic method in three different solutions and, in addition, the changes of corrosion potentials over time were also determined. The corrosion rates, corrosion potentials, their changes over time and their cathodic Tafel slopes were determined. All alloys tested showed ion leakage in corrosive media. Titanium exhibited the least, but alloys with tin and cobalt content displayed the greatest corrosion tendencies. Alloys with iron and copper corroded in the acid media, conversely alloys containing chromium, nichel and molybdenum proved to be resistant to corrosion. The recurrent castings were also corrosion resistant.