Journal of

---

Introduction: Organic antibacterial materials have been used as insecticides and bactericides for many years. Unfortunately, high temperatures in manufacturing process reduce their antibacterial properties. However, inorganic materials of antibacterial agents have excellent bacterial resistance and thermal stability. Over the past few decades, inorganic nanoparticles whose structures exhibit significantly novel and improved physical, chemical and biological properties and functionality due to their nano-scale size have elicited much interest. methods:The aim of this study was to investigate the antibacterial properties of one kind of nano-specimen (TiO2 nanoparticle) against Escherichia coli and Streptococcus aureus. Our study was research perusal. In the first study, the optical density of E. coli and S. aureus cultures were observed in the presence of 0.01%, 0.75% and 1.5% of TiO2. In the second study, 6.3 log CFU/ml of E. coli and S. areus were separately exposed to 1.5% TiO2 at 37 ºC in water. In third study, we studied thew growth of E.coli in solid medium with and without nanoparticles. Results: The presence of 0.01% TiO2 nanoparticles didn’t have a statistically significant effect, but in the presence of 0.75% and 1.5% nanoparticles, the bacterial colonies decreased significantly. In the control group, bacterial cells survival was nearly 13 days, while complete cell death of E. coli was seen when 1.5% TiO2 was applied for 24 hours. The same experiment for S. aureu, showed that complete cell death occured when the bacterial culture was exposed to 1.5% TiO2 for 16 hours.. It was shown that presence of 1.5% TiO2 in the solid medium suppressed the growth of E. coli 5.6 times more (p < 0.001). Discussion: Our findings showed antibacterial effects of TiO2 nanoparticles against both bacteria, but S. areus bacteria were more sensitive to nanoparticles as compared to E. coli bacteria

---

Introdution: The aim of this study was to investigate the physico-chemical properties, surface charge and cytotoxicity of nanocomposite formulations for the design of lipid nano-systems with maximum loading for nucleic acids in bone marrow cancer.
Methods For this study, six types of liposomes with different compositions were synthesized using DPPC, cholesterol, DSPE-mPEG (2000) and DOTAP. Then, nanosystems were evaluated for particle size, surface charge, cytotoxicity and loading rate of miRNA in two MG-63 and SaOs2 cell lines, which are human cell bone marrow cell lines.
Results: All nano-systems were monodisperse. Among the systems, the F6 formula has the lowest toxicity and the highest load of miRNA-143, due to the presence of a suitable amount of DOTAP and PEG phospholipid in the liposome structure.
Conclusion: Liposomal formulation with a suitable percentage of DOTAP cationic phospholipid can be used as a successful carrier for the transport of miRNA in the gene therapy process for the treatment of various cancers, especially metastatic types.

---

Introdution: The present study was conducted to evaluate the effect of miR-143 on the expression of Bcl2 gene at the level of mRNA, cell cytotoxicity in the SaOs-2 cell line (Osteosarcoma) and Hum 63 (Human primary bone cells).
Methods: In this experimental study, miR-143 was introduced into the SaOs-2  and Hum 63 cell by the lipofectam 2000 system. Then, the effects of miR-143 on cytotoxicity (72 hours) and expression of Bcl2 gene were measured by the MTT tests and Real Time Pcr protocols, respectively.
Results: The results showed that the lipofectamine 2000 system had no toxicity in both Hum63 and SaOs2 cell lines by itself. SaOs2 cancer cells were more susceptible to miR-143 and Lipo / miR-143 compared to Hum63 cells. The highest reduction in SaOs2 cells was observed after the treatment with Lipo / miR-143 (p <0.05). Furthermore, according to the results, transfection of miR-143 by lipofectamine 2000 into the cell, compared to cell-treated alone by miR-143, significantly reduced Bcl2 expression (p <0.05).
Conclusion: The lipoprotein 2000 system can be effective in absorbing miR-143 into the cells. By targeting various cellular pathways, including the expression level of the Bcl2 gene, miR-143 can be effective in the treatment of bone cancer (Osteosarcoma).