The effect of silver nanoparticles on composite shear bond strength to dentin with different adhesion protocols

Abstract In Dentistry, restorative materials and oral bacteria are believed to be responsible for restoration failure. To make long-lasting restorations, antibacterial agents should be made. Inorganic nanoparticles and their nano composites are applied as good antibacterial agents. Objective The purpose of this study was to investigate the effect of silver nanoparticles on composite shear bond strength using one etch and rinse and one self-etch adhesive systems. Material and Methods Silver nanoparticles were prepared. Transmission electron microscope and X-ray diffraction were used to characterize the structure of the particles. Nanoparticles were applied on exposed dentin and then different adhesives and composites were applied. All samples were tested by universal testing machine and shear bond strength was assesed. Results Particles with average diameter of about 20 nm and spherical shape were found. Moreover, it was shown that pretreatment by silver nanoparticles enhanced shear bond strength in both etch and rinse, and in self-etch adhesive systems (p≤0.05). Conclusions Considering the positive antibacterial effects of silver nanoparticles, using them is recommended in restorative dentistry. It seems that silver nanoparticles could have positive effects on bond strength of both etch-and-rinse and self-etch adhesive systems. The best results of silver nanoparticles have been achieved with Adper Single Bond and before acid etching.

Evaluation of cisplatin and cisplatin-loaded magnetic iron oxide nanoparticles on BCL2 and BAX genes in the breast cancer T47D cell line

Breast cancer is the second leading cause of cancer death in women. Cisplatin is a traditional cancer drug commonly used in chemotherapy for killing cancer cells. Modulation at the mRNA levels of apoptotic related genes often correlate with the sensitivity of various types of cancer cells to chemotherapeutic agents. Nanoparticulate drug delivery systems are being developed to effectively deliver smaller doses of chemotherapeutic agents and control drug distribution in the body. In this study, we evaluate the expressions of BCL2 and BAX genes in T47D treated with cisplatin and cisplatin nanoparticles, which can result in a new approach to breast cancer therapy. In this study, we treated T47D cells with different concentrations of cisplatin and cisplatin nanoparticles at 48 h. The IC50 was determined. We extracted RNA by using RNX solution, after which cDNA was synthesized. The precise primers for the BCL2, BAX and TBP genes were designed by specific software. The quantity of BCL2 and BAX gene expression compared to TBP gene [reference gene] was analyzed using real-time PCR. BCL2 and BAX gene expression levels in T47D cells treated by cisplatin were 0.7 [BCL2] and 1.48 [BAX], in T47D cells treated with cisplatin-loaded nanoparticles, the gene expressions were 0.03 [BCL2] and 2.41 [BAX]. In this study, the results have shown that cisplatin-loaded nanoparticles are effective anticancer agents. Cisplatin nanoparticles induce apoptosis in human breast cancer cell lines. We have shown that cisplatin nanoparticles strongly increased cytotoxicity in comparison to the free drug in the T47D cell line

[Up regulation of CD82 gene in prostate cancer PC-3 cell line treated with silibinin]

Prostate cancer is one of the most common cancer in the developed countries. Most of cancer deaths are due to development of metastasis. Hence, prevention of metastasis is critical. Silibinin is a flavonoid component that inhibits cell proliferation and causes cell death of human prostate cancer. In this study, the expression of CD82 gene in PC-3 cells treated with escalating concentrations of silibinin was evaluated which can result in new view for prostate cancer therapy. In this study, PC-3 cells were treated with different concentrations of silibinin for 24h. The LD50 was determined. RNA was extracted by trizol, then cDNA was synthesized. Precise primers were designed for CD82 and GAPDH genes by specific software. Quantity of CD82 gene expression compare to GAPDH gene in different concentrations of silibilin was analyzed using very sensitive quantitative Real-time PCR. CD82 gene expression in PC-3 cells treated with 100, 150 and 200?g/ml of silibinin at 24h was increased by 1.97 +/- 0.26 [P<0.05], 3.00 +/- 0.26 and 3.43 +/- 0.43 [P<0.01], respectively. The results of quantitative Real-time PCR indicated that silibinin can probably decrease metastasis, by up-regulation of CD82 metastasis suppressor gene in PC-3 cells