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ABSTRACT
Background: Sodium arsenite (SA) recently has been recommended to be used in malignancy therapy. Our studies showed, SA in short and long period of treatment caused reduction of rats Bone Marrow Mesenchymal Stem Cells (MSCs) viability and induced caspase dependent apoptosis. The aim of this study was to investigate the effect of SA on osteogenic differentiation of MSCs.
Methods: MSCs were extracted and expanded to third passage, then cultured in DMEM supplemented with osteogenic media in presence of 1 and 25nM of SA for 21 days. The viability and the level of mineralization were determined using MTT assay and alizarin red respectively. In addition morphology and nuclear diameter of the cells were studied with the help of fluorescent dye. Furthermore, calcium content and alkalinphosphatase activity also were estimated using commercial kit. Data was statistically analyzed and the P<0.05 was taken as the level of significant.
Results: The viability and mineralization of the cells treated with SA reduced significantly (P<0.05) after tenth day in compare with control. Also, chromatin condensation, reduction of nuclei diameter and cytoplasm shrinkage were observed in the cell treated with 1 and 25 nM concentrations. The calcium and alkalinphosphatase activity of the cells decreased significantly with 1 and 25 nM concentrations of SA when compared with control.
Conclusion: Adverse effect of SA was observed on osteogenic differentiation of MSCs at 1 and 25 nM due to disruption of mineralization. We strongly suggest more investigation to be run on this chemical with respect to the therapy of the malignant patients.

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ABSTRACT Background: Occupational exposure studies indicate that formaldehyde exposure causes temporary and consistent effects on industrial workers exposed to formalin. Case: The case was a 36-year-old man who had developed intravascular hemolytic anemia caused by formalin after inhalation exposure. Formalin is a clear solution of 37% formaldehyde in water. The primary route of exposure to formaldehyde is inhalation. The case was presented with severe Coomb's negative hemolytic anemia with hemoglobinuria and was treated successfully with therapeutic red cell transfusion and exposure removal. Conclusion: All employers must provide a safe and healthy workplace for prevention of harmful effects of formalin. Elimination of formalin from workplace, implementation of local and general ventilation, and using proper protective equipments are the most effective methods in the workplace.

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Background: The aim of this study was to evaluate and compare the hepatotoxicity as well as antioxidants activities of hydromethanolic extract of six common traditional species (Origanum vulgar, Pterocarya fraxinifolia, Ferula assafoetida, Artemisia dracunculus, Rosmarinus officinalis, and Valerian officinalis) in order to find a safe antioxidant source.
Methods: This research project was performed at Toxicology and Animal Poisoning Research Center, University of Tehran (Tehran, Iran), in 2016. The HepG2 cells viability was examined by LDH and MTT techniques following treatment with different concentrations of selected herbal hydroethanolic extracts for 72 h. Furthermore, assessment of antioxidative properties of the extracts was carried out by various scavenging models including DPPH and FRAP.
Results: The highest cytotoxicity was displayed by F. asafoetida extract (IC50= 67.3 µg/ml). R. Officinalis and A. dracunculus extracts were noted as non-toxic due to the high effective dose. Interestingly, V. officinalis extract indicated stimulating effects on cell growth/ proliferation with ED50 values of 20.9 µ/ml. The highest and lowest antioxidant capacities refer to R. officinalis and V. officials. In DPPH assay, the IC50 value of R. officinalis and V. officinalis extracts was found to be 39.82 and 371.77 µg/ml, respectively. FRAP values of R. officinalis and V. officials were 2754.07 and 561.14 µM/g, respectively.
Conclusion: This study identified R. officinalis extract as a natural non-toxic agent with remarkable antioxidant potential in phytomedicine.