The thioredoxin reductase activity and hypoxia-inducible factor 1 alpha level in anaerobic and aerobic macrophages.

OBJECTIVES: This study was aimed to demonstrate the thioredoxin reductase (TrxR) activities and Hypoxia-Inducible Factor 1 alpha (HIF-1α) levels in macrophage cell line incubated in aerobic and anaerobic settings. BACKGROUND: Pathological situations including inflammatory disorders are associated with the infiltration of phagocyte system cells into damaged tissues. Whenever the environment of tissues converts into hypoxic conditions, phagocytic cells develop an adaptive mechanism in order to fulfill their defense functions. MATERIALS AND METHODS: The macrophage cells were prepared as two replications both for aerobic and anaerobic media. The E. coli bacteria were inoculated onto the some macrophage culture mediums. TrxR and HIF-1α levels of the samples, obtained from all growth cultures, were measured with the ELISA. RESULTS: On the 5th and 6th day, there was a continuous increase in the count of bacteria in the aerobic medium, while a continuous decrease in the count of bacteria in the anaerobic medium.The TrxRand the HIF-1α levels in the groups with anaerobic and aerobic macrophages with or without E. coli bacteria were evaluated. A statistically significant difference was found between these groups in terms of TrxR and HIF-1α levels (p < 0.05). CONCLUSIONS: Increased TrxR and HIF-1α levels were thought to have an effect on the adaptation of the macrophages in the anaerobic environment (Tab. 5, Fig. 2, Ref. 23).

Which is the most effective disinfection method in primary root canals: Conventional or newly developed ones?

BACKGROUND: The aim of the study was to evaluate the antimicrobial activity of the-potassium-titanyl-phosphate--the KTP laser and ozone in of primary root canals. MATERIALS AND METHODS: Sixty primary incisor teeth were selected. The specimens were inoculated with 10 mL Enterococcus faecalis (E. faecalis). Groups: The KTP laser (1,5 W); gaseous ozone (150 s); sodium hypochlorite (NaOCl); saline group. Sterile paper points used to sample bacteria from the canals to tubes containing 5 mL of brain heart infusion broth. Then, 10 mL suspension was incubated in culture media for 24 h. Data were analyzed statistically using Kruskal-Wallis and Mann-Whitney U-test. RESULTS: There were statistically significant differences between all groups (P<0.05). Complete sterilization was achieved in the 2.5% NaOCl group. The number of bacteria were significantly reduced in experimental groups in comparison to the saline group. CONCLUSION: The KTP laser and ozone application provided a significant antibacterial effect in primary root canals; however, 2.5% NaOCl was superior.

Lessons learned from implementing Clostridium difficile-focused antibiotic stewardship interventions.

OBJECTIVE: To determine whether controlling the prescription of targeted antibiotics would translate to a measurable reduction in hospital-onset Clostridium difficile infection (CDI) rates. DESIGN: A multicenter before-and-after intervention comparative study. SETTING/PARTICIPANTS: Ten medical centers in the greater New York region. Intervention group comprised of 6 facilities with early antimicrobial stewardship programs (ASPs). The 4 facilities without ASPs made up the nonintervention group. INTERVENTIONS/METHODS: Intervention facilities identified target antibiotics using case-control studies and implemented ASP-based strategies to control their use. Pre- and postintervention hospital-onset CDI rates and antibiotic consumption were compared for a 20-month period from June 2010 to January 2012. Antibiotic usage was compared using defined daily dose, days of therapy, and number of courses prescribed. Comparisons used bivariate and regression techniques. RESULTS: Intervention facilities identified piperacillin/tazobactam, fluoroquinolones, or cefepime (odds ratio, 2.0-9.8 in CDI case patients compared with those without CDI) as intervention targets and selected several interventions (all included a component of audit and feedback). Varying degrees of success were observed in reducing antibiotic consumption over time. Total target antibiotic use significantly decreased (P < .05) when measured by days of therapy and number of courses but not by defined daily dose. Intravenous moxifloxacin and oral ciprofloxacin use showed significant reduction when measured by defined daily dose and days of therapy (P ≤ .01). Number of courses with all forms of these antibiotics was reduced (P < .005). Intervention hospitals reported fewer hospital-onset CDI cases (2.8 rate point difference) compared with nonintervention hospitals; however, we were unable to show statistically significant decreases in aggregate hospital-onset CDI either between intervention and nonintervention groups or within the intervention group over time. CONCLUSIONS: Although decreases in target antibiotic consumption did not translate into reductions of hospital-onset CDI in this study, many valuable lessons (including implementation strategies and antibiotic consumption measures) were learned. The findings can inform potential policy decisions regarding incorporating control of CDI and ASP as healthcare quality measures.

Apical extrusion of intracanal bacteria following use of various instrumentation techniques.

AIM: To evaluate the number of bacteria extruded apically from extracted teeth ex vivo after canal instrumentation using a manual technique and three engine-driven techniques utilizing nickel-titanium instruments (K3, RaCe, and FlexMaster). METHODOLOGY: Seventy extracted human mandibular premolar teeth with similar dimensions were used. Access cavities were prepared and root canals were then contaminated with a suspension of Enterococcus faecalis and then dried. The contaminated roots were divided into four experimental groups of 15 teeth each and one control group of 10 teeth. G1. RaCe group: the root canals were instrumented using RaCe instruments. G2. K3 group: the root canals were instrumented using K3 instruments. G3. FlexMaster group: the root canals were instrumented using FlexMaster instruments. G4. Manual technique group: the root canals were instrumented using K-type stainless steel instruments. G5. CONTROL GROUP: no instrumentation was attempted. Bacteria extruded from the apical foramen during instrumentation were collected into vials. The resultant microbiological samples were removed from the vials and then incubated in culture media for 24 h. The number of colony-forming units (CFU) was determined for each sample. The data obtained were analysed using the Kruskal-Wallis one-way analysis of variance and Mann-Whitney U-tests, with alpha = 0.05 as the level for statistical significance. RESULTS: There was a significant difference between experimental-control and engine-driven-manual technique groups (P < 0.05). The manual technique was associated with the greatest extrusion of microorganism. CONCLUSIONS: All instrumentation techniques extruded intracanal bacteria apically. No significant difference was found in the number of CFU among the engine-driven techniques; manual techniques extruded significantly more microorganisms.

Apical extrusion of intracanal bacteria following use of two engine-driven instrumentation techniques.

AIM: To evaluate the number of bacteria extruded apically from extracted teeth ex vivo after canal instrumentation using the two engine-driven techniques utilizing nickel-titanium instruments (ProTaper and System GT). METHODOLOGY: Forty extracted single-rooted human mandibular premolar teeth were used. Access cavities were prepared and root canals were then contaminated with a suspension of Enterococcus faecalis and dried. The contaminated roots were divided into two experimental groups of 15 teeth each and one control group of 10 teeth. Group 1, ProTaper group: the root canals were instrumented using ProTaper instruments. Group 2, System GT group: the root canals were instrumented using System GT instruments. Group 3, control group: no instrumentation was attempted. Bacteria extruded from the apical foramen during instrumentation were collected into vials. The microbiological samples from the vials were incubated in culture media for 24 h. Colonies of bacteria were counted and the results were given as number of colony-forming units. The data obtained were analysed using the Kruskal-Wallis one-way analysis of variance and Mann-Whitney U-tests, with alpha = 0.05 as the level for statistical significance. RESULTS: There was no significant difference as to the number of extruded bacteria between the ProTaper and System GT engine-driven systems (P > 0.05). CONCLUSIONS: Both engine-driven nickel-titanium systems extruded bacteria through the apical foramen.

In vitro potency and stability of fortified ophthalmic antibiotics.

PURPOSE: This study evaluates the in vitro potency, stability and contamination of the fortified ophthalmic antibiotic preparations of cefazolin, vancomycin, gentamicin and tobramycin stored for 4 weeks. The effects of the different solvents and storage temperatures on the antimicrobial potency and stability were also examined. METHODS: The fortified stock solution of cefazolin and vancomycin were prepared by reconstituting with 0.9% sodium chloride and with artificial tears. Gentamicin and tobramycin were prepared by adding parenteral forms into their commercial ophthalmic solutions. The antimicrobial potency was measured by the minimum bactericidal concentration for cefazolin (33.3 mg/mL) and vancomycin (31 mg/mL) against Staphylococcus aureus, and for tobramycin (13.5 mg/mL) and gentamicin (13.5 mg/mL) against Pseudomonas aeruginosa. The stability of solution was evaluated by measuring absorbance spectra and pH. During the study period the levels of contamination of the stock solutions were examined by culturing on blood and on Sabouraud-dextrose media. RESULTS: There were no differences in the antimicrobial potency of the cefazolin, vancomycin and tobramycin within the 4-week period; however, the potency of gentamicin was decreased at both temperatures after 21 days. It was found that different solvents or storage temperatures had no effect on the potency. Throughout the 4-week period, no change was found in the absorbance spectra of gentamicin and tobramycin, whereas the absorbance spectra of cefazolin and vancomycin stored at 24 degrees C increased in both of the solvents used (P<0.05). In all of the antibiotics, pH changed at 24 degrees C after 7-10 days; however, at 4 degrees C, only the pH of tobramycin exhibited changes after 14 days (P<0.05). No contamination was detected in the stock solutions during the study period. CONCLUSION: Topical fortified antibiotic solutions used for longer than 7 days should be stored at < or =4 degrees C, those stored at 24 degrees C should be discarded after 7 days.

Sources of self-identity among Turkish adolescents.

As part of the International Self-Identity Research Project, this study explored sources of identity among Turkish adolescents. The interview sample consisted of three male and three female high school students in Ankara, Turkey. The results indicated that social, familial, personal, physical, and moral-ethical dimensions contributed to adolescents' definitions of self, but to different degrees. Social and familial dimensions were very influential and were used as reference points for defining self in other areas. Physical and personal aspects of identity were also apparent, but were not as salient as social and familial dimensions. Patriotism and religion played a role in moral-ethical identity. Overall, self-identity influenced emotional state, cognitive and behavioral functioning, and social relations to a significant degree.