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Background and Objective: Fish as well as other aquatic animals have become an important source of protein diets. Heavy metals due to their specific physical and chemical characteristics as well as their side effects on various ecosystems are considered as a major contaminator of marine environments. Therefore determine determination of Zinc (Zn), Copper (Cu), Cobalt (Co) and Manganese (Mn) intensity in Rutilus frisii kutum and Cyprinus carpio fishes of Caspian sea. Materials and Methods: In this descriptive study, levels of Zinc, Copper, Cobalt and Manganese were evaluated, using flame atomic absorption spectroscopy (A.S.S) technique, in tissues of two commonly consumed fish in Iran, namely Rutilus frisii kutum and Cyprinus carpio, collected from the southern coastline of the Caspian sea. Results: The mean±SD average concentration of Zn, Cu, Co and Mn were detected as (μg g-1) dry weight of Rutilus frisii kutum’s tissues were 29.97±0.57, 9.45±0.09, 0.30±0.01 and 0.20±0.01, respectively. These values for Cyprinus carpio were detected as: 30.20±0.14, 9.14±0.07, 1.08±0.03 and 0.71±0.02, respectively. Conclusion: This study showed that, the concentration of Zn, Cu and Co in Rutilus frisii kutum, Cyprinus carpio fish tissues were higher than standard base of Brian.

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Background and Objective: Some problems such as low viability and apoptosis after injection to the body because of exposure to toxic factors such as hypoxia, thermal stress, oxidative stress and food deprivation are encountered with stem cell application. It is suggested that preconditioning of the cells with cytotoxic factors before injection could enhance their efficiency. This study was done to determine the mesenchymal stem cell proliferation exposed to hypoxia by cobalt chloride. Methods: In this experimental study, Mesenchymal stem cells were isolated from rat bone marrow and cultured at least for four times. The cells were cultured in 96 well plates and treated with different concentration (0, 5, 10, 20, 50, 70, 90, 100, 120, 150 and 200 µM) of cobalt chloride for 6, 12, 24 and 46 hours. Cell proliferation was detected by MTT assay [3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide]. Results: The cells isolated from bone marrow were propagated easily in culture condition. The cells morphology was not altered after exposure to cobalt chloride. Preconditioning of mesenchymal stem cells with 120 µM for 6 hours, 20µM for 12 and 24 hours and 5µM for 48 hours significantly improved cell proliferation after hypoxia in cell culture (P<0.05). Conclusion: Hypoxia preconditioning increases proliferation of mesenchymal stem cell.

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Background and Objective: The application of different nanoparticles using green synthesis is increasing due to fewer complications. This study was conducted to identify the effect of cobalt ferrite nanoparticles synthesized with sumac extract on changes in biochemical and histological factors in rats.
Methods: In this experimental study, 30 five-month-old male Wistar rats with an approximate weight of 250-300 mg/kg of body weight were divided into three groups: The control group (saline receiving), the experimental groups receiving intraperitoneal cobalt ferrite nanoparticles synthesized with sumac extract at a dose of 10 and 20 mg/kg of body weight. Serum and tissue samples (liver, kidney, and spleen) were isolated. Serum concentrations of urea, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatinine were determined. The photometric method was used to measure liver enzymes, the calorimetric method without omitting proteins based on the Jaffe method was used to measure creatinine, and the urease-glutamate dehydrogenase (GLDH) method was used to measure urea. Tissue samples were assessed by hematoxylin-eosin staining. Transmission electron microscopy (TEM) and scanning electron microscope (SEM) microscopic studies were used for microscopic investigations.
Results: No statistical significance was observed in blood samples and factors (urea, creatinine, ALT, and AST) in the experimental groups compared to the control group. Similarly, in the morphological investigation, the size of the liver, kidney, and spleen of the groups receiving cobalt ferrite nanoparticles synthesized with sumac extract was normal compared to the control group.
Conclusion: Cobalt ferrite nanoparticles synthesized with sumac had no toxic effect on the rats’ liver, spleen, and kidney tissues.