Extremely low-frequency magnetic field induces manganese accumulation in brain, kidney and liver of rats.

The aim of the present study was to determine the effects of extremely low-frequency magnetic field (ELF-MF) on accumulation of manganese (Mn) in the kidney, liver and brain of rats. A total of 40 rats were randomly divided into eight groups. Four control groups received 0, 3.75, 15 and 60 mg Mn per kg body weight orally every 2 days for 45 days, respectively. The remaining four groups received same concentrations of Mn and were also exposed to ELF-MF (1.5 mT; 50 Hz) for 4 h for 5 days a week during 45 days. Following the last exposure, kidney, liver and brain were taken from all rats and they were analyzed for Mn accumulation levels using an inductively coupled plasma-optical emission spectrometer. In result of the current study, we observed that Mn levels in brain, kidney and liver were higher in Mn groups than in control groups. Mn levels in brain, kidney and liver were also higher in Mn plus ELF-MF groups than in Mn groups. In conclusion, result of the current study showed that the ELF-MF induced manganese accumulation in kidney, liver and brain of rats.

An evaluation of nitric oxide, folate, homocysteine levels and lipid peroxidation in postmenopausal osteoporosis.

OBJECTIVES: In the current study, the risk coefficients of nitric oxide (NO), folate, homocysteine levels and lipid peroxidation in postmenopausal osteoporotic women were determined. MATERIAL AND METHODS: Bone mineral density was determined by dual-energy X-ray absorptiometry. The levels of serum lipid peroxidation products such as the thiobarbituric acid adduct of malondialdehyde (MDA) were measured spectrophotometrically. Plasma folate and homocysteine (Hcy) levels were measured by enzyme chemiluminescence immunoassay. Plasma nitrite levels were measured with the Griess reaction RESULTS: The odds ratios and 95% Confidence Intervals (CI) of the variables MDA, folate, NO, body-mass index (BMI), menopause age and age were found significant. MDA, NO and folate variables were found statistically significant in the analysis of receiver operating charecteristic (ROCs). The areas under the curve (AUCs, 95% CI) of MDA, NO and folate were found to be statistically significant. CONCLUSIONS: The current study indicates that NO, MDA and folate are risk variables for postmenopausal osteoporosis.

Retentive force of three fiber-reinforced resin composite posts and a zirconia post cemented with two adhesive luting agents: in vitro study.

By means of a pull-out test, this study compared the retentive force of three fiber-reinforced resin composite posts and a zirconia post. These posts were cemented using two different dual-polymerizing adhesive resin luting agents. Forty freshly extracted canines were selected for the study. All tooth root were endodontically treated and the post spaces prepared. The posts were luted using luting agents according to the manufacturers' guidelines. A tensile force was applied, and all data were collected and analyzed statistically. Glass fiber posts that were luted with Panavia F (Group 3) had the highest median load (3.610 N), while zirconia posts that were luted with RelyX ARC (Group 8) had the lowest median load (0.926 N). Among the different post systems that were luted with Rely X ARC, significant differences were observed in their median tensile loads (p < 0.047). When comparing between Panavia F and RelyX ARC of each post system, a significantly higher tensile load was seen with zirconia posts luted with Panavia F (Group 7) (p < 0.032).