The role of lead and cadmium in deciduous teeth and saliva on dental caries in children residing in Tehran, Iran.

BACKGROUND: Lead (Pb) and Cadmium (Cd) are important environmental contaminants. There is no biological monitoring of exposure to these heavy metals and their potential effect on dental caries in children in Tehran, Iran, a polluted megacity. Therefore, the present study investigated the potential association between Pb and Cd levels in primary teeth and saliva and dental caries. METHODS: In a cross-sectional design, 211 children aged 6-11 years referred to Tehran University of Medical Sciences, School of Dentistry and residing in Tehran were examined. Pb and Cd levels of exfoliated primary teeth and stimulated saliva were determined by atomic absorption spectrophotometry (AAS). Dental caries prevalence was evaluated according to WHO criteria. Socioeconomic status, oral hygiene behavior, snacking frequency and salivary pH data were acquired as confounding factors. Frequency and percentages were reported for categorical variables, mean and standard deviation (SD) for continuous variables, and geometric mean for skewed continuous variables. A simple linear regression and Pearson correlation tests were used for statistical analyses. P-values < 0.05 were considered as significant. RESULT: The mean (95 % confidence interval) Pb and Cd levels in teeth were 213.26 ppb (164.29-274.84) and 23.75 ppb (20.86-27.05), respectively. The mean Pb and Cd levels in saliva were 11.83 ppb (10.71-13.06) and 3.18 ppb (2.69-3.75), respectively. Furthermore, Pb and Cd in primary teeth and saliva were not associated (p > 0.05) with socioeconomic status, oral hygiene behavior and snacking frequency CONCLUSION: This study showed no association between Pb and Cd concentrations in primary teeth and in saliva with dental caries prevalence.

Preparation and Characterization of Nanoparticle ß-Cyclodextrin:Geraniol Inclusion Complexes.

The aim of the present study was to formulate ß-cyclodextrin (ß-CD) nanoparticles loaded with geraniol (GR) essential oil (EO) with appropriate physicochemical properties. Complexation of GR with ß-CD was optimized by evaluation of four formulations, using the co-precipitation method, and the encapsulation efficiency (EE), loading, size, particle size distribution (PDI) and zeta potential were investigated. Further characterization was performed with nuclear magnetic resonance spectroscopy (1H NMR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and infra-red (IR) spectroscopy analysis. Results showed that the physicochemical properties of the nanoparticles were affected by GR content in formulations that yielded nanoscale-size particles ranging from 111 to 258 nm. The highest encapsulation efficiency (79.4 ± 5.4%) was obtained when the molar ratio of EO to ß-CD was 0.44: 0.13 with negative zeta potential (-21.1 ± 0.5 mV). The 1H-NMR spectrum confirmed the formation structure of the EO and ß-CD nanoparticle complex. Complexation with geraniol resulted in changes of IR profile, NMR chemical shifts, DSC properties, and SEM of ß-cyclodextrin. Inclusion complex of essential oil with ß-cyclodextrin was considered as promising bioactive materials for designing functional food.

The influence of feeding linoleic, gamma-linolenic and docosahexaenoic acid rich oils on rat brain tumor fatty acids composition and fatty acid binding protein 7 mRNA expression.

BACKGROUND: Experimental studies indicate that gamma linolenic acid (GLA) and docosahexaenoic acid (DHA) may inhibit glioma cells growth but effects of oral consumption of these fatty acids on brain tumor fatty acid composition have not been determined in vivo. METHODS: GLA oil (GLAO; 72% GLA), DHA oil (DHAO; 73% DHA) were fed to adult wistar rats (1 mL/rat/day) starting one week prior to C6 glioma cells implantation and continued for two weeks after implantation. Control group were fed same amount of high linoleic acid safflower oil (74-77% linoleic acid). Fatty acid composition of tumor samples was determined in a set of 8-12 animals in each group and serum fatty acid in 6 animals per each group. Gene expression of tumor fatty acid binding protein 7 (FABP7), epidermal growth factor receptor (EGFR), peroxisome proliferator activated receptor gamma (PPAR-gamma) and retinoid x receptor-alpha (RXR-alpha) were determined in a set of 18 animals per group. RESULTS: DHAO feeding increased EPA of brain tumors and decreased ratio of n-6/n-3 fatty acids. Serum levels of EPA were also increased in DHAO group. A similar trend in serum and tumor levels of DHA were observed in DHAO group but it did not achieve statistical significance. GLAO increased serum concentration of GLA but had no significant effect on tumor GLA or dihomo-gamma linolenic acid (DGLA) concentrations. Gene expression of FABP7 was up-regulated in tumors of DHAO group but no other significant effects were observed on EGFR, PPAR-gamma or RXR-alpha expression, and expression of these genes in tumors of GLAO were not different from SFO group. CONCLUSION: Dietary supplementation of DHA containing oil could be an effective way to increase levels of long chain n-3 fatty acids in brain tumors and this increase may be mediated partly by up-regulation of FABP7 expression.