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Background: Bacterial cellulose synthesized by acetobacter xylinum is a harmless microbial product with unique characteristics as an ideal dress that many studies have been done on. The aim of this study was to consider the capability of this product in absorption and release of tetracycline hydrochloride. Indication of this capability can pave the way for supplying a new dressing containing antibiotic from bacterial cellulose. Materials and Methods: In this experimental study, cellulose sheet was initially impregnated on aqueous solution of tetracycline hydrochloride. Then the release process was considered in diluted water and normal saline. Ultra violet spectrophotometry method was applied to the detection of the antibiotic during absorption and release processes. Results: The results of data analysis demonstrated that bacterial cellulose has a great potential in absorption of tetracycline hydrochloride and can release it in a wet environment. Conclusion: Considering the advantages of bacterial cellulose over traditional dressings, the results of this study can provide the ground for further research on supplying an ideal dressing containing antibiotic from this microbial product.

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Background: Biochemical studies have shown that iron produces reactive oxygen species via Haber-Weiss and Fenton reactions. The goal of this study is to examine the role of iron in oxidation of human hemoglobin and its structural changes in erythrocytes. Materials and Methods: In this experimental study, blood samples from healthy subjects were incubated aerobically with the iron containing metal catalyzed oxidation (MCO) system in the presence of 0.036, 0.7, 0.14, 0.28, 0.57, 1.14, 2.28, 4.55, 9.09, and 18.18 micromole of iron. Structural changes in Hb were followed by spectrophotometric analysis from 300 to 650 nm. In addition, carbonyl assay was performed for estimation of protein oxidation in globin chains. Results: Based on the results, oxy-Hb decreased up to 68% in iron-treated erythrocytes. Decrease in the absorbance ratio (A577, A542 wavelength) indicated the conversion of oxy-Hb to met-Hb. Also, met-Hb concentration was 4.7 fold of hemichrome. After 24 hours of incubation, oxyHb concentration decreased up to 50% and metHb concentration increased up to 85%. Moreover, increase in iron concentration resulted in significant carbonyl formation in hemoglobin. Conclusion: These findings indicate that Hb oxidation instead of its oxygenation leads to anemia and hypoxia. The findings of this study may be directly applicable to oxidation states during hemolytic diseases and iron treatment.

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Background: The presence of nitrate in drinking water causes various health and environmental problems. The aim of this study was to evaluate the efficacy of nitrate reduction by Fe/H2O2 process and adsorption on activated carbon. Materials and Methods: This experimental study investigated nitrate oxidation by advanced oxidation process of Fe°/FeІІ/FeШ/H2O2 at pH 2-10, nitrate concentrations of 50-300 mg/L. After adjusting the pH, 0.5, 1, 2, 5, and 10 g/L values of GAC, PAC, H2O2/GAC, and Fe/H2O2/GAC together with H2O2 at retention times of 15, 30, 45, 60, and 90 minutes, respectively, were added and mixed. Results: At retention time of 10 minutes and 0.5 mL H2O2 and 1 g/L from Fe°, FeІІ, and FeІІІ, the removal efficacy was 88.5, 84 and 78%, respectively. At 50 mg/L nitrate and 0.5, 1, and 10 mg/L GAC concentrations, the removal efficacy was 56.5, 93.6, and 82.6%, respectively. The nitrate removal efficiency at pH=4 was approximately 50%, whereas at pH=3 with 30% efficacy, it increased to 80%. Conclusion: Modified Fe/H2O2 process with iron nano-particles and activated carbon adsorption can effectively reduce nitrate under optimal conditions. The use of activated carbon at a concentration of 1 g/L increased the removal efficiency of nitrate to 90%.