The ultimate goal of tissue engineering is to design and fabricate functional human tissues that are similar to natural cells and are capable of regeneration.Preparation of cell aggregates is one of the important step...The ultimate goal of tissue engineering is to design and fabricate functional human tissues that are similar to natural cells and are capable of regeneration.Preparation of cell aggregates is one of the important steps in 3D tissue engineering technology,particularly in organ printing.Two simple methods,hanging drop(HD)and conical tube(CT)were utilized to prepare cell aggregates.The size and viability of the aggregates obtained at different initial cell densities and pre-culture duration were compared.The proliferative ability of the cell aggregates and their ability to spread in culture plates were also investigated.In both methods,the optimum average size of the aggregates was less than 500μm.CT aggregates were smaller than HD aggregates.5,000 cells per drop HD aggregates showed a marked ability to attach and spread on the culture surface.The proliferative ability reduced when the initial cell density was increased.Comparing these methods,we found that the HD method having better size controlling ability as well as enhanced ability to maintain higher rates of viability,spreading,and proliferation.In conclusion,smaller HD aggregates might be a suitable choice as building blocks for making bioink particles in bioprinting technique.展开更多
AIM: To study the combinative effects of nanocerium and selenium in a murine model of diabetes. METHODS: Cerium oxide (CeO2) nanoparticles (60 mg/kg per day) and sodium selenite (5 μmol/kg per day) aloneor in combina...AIM: To study the combinative effects of nanocerium and selenium in a murine model of diabetes. METHODS: Cerium oxide (CeO2) nanoparticles (60 mg/kg per day) and sodium selenite (5 μmol/kg per day) aloneor in combination, or the metal form of CeO2 (60 mg/kg) were administered for 2 wk by intraperitoneal injection to streptozotocin-induced diabetic rats. At the end of treatment blood was collected, liver tissue dissected and then oxidative stress markers, extent of energy depletion and lipid prof ile were evaluated.RESULTS: Antioxidant enzymes and high density lipoprotein decreased whereas oxidative stress, adenosine diphosphate/adenosine triphospahte levels, cholesterol, triglyceride and low density lipoprotein increased on induction of diabetes. All were improved by a combination of nanocerium and sodium selenite. There was a relative amelioration by CeO2 nanoparticles or sodium selenite alone, but the metal form of CeO2 showed no signif icant improvement. CONCLUSION: The combination of nanocerium and sodium selenite is more effective than either alone in improving diabetes-induced oxidative stress.展开更多
基金funded by a grant provided from Endocrinology and Metabolism Research Center,Tehran University of Medical Sciences.
文摘The ultimate goal of tissue engineering is to design and fabricate functional human tissues that are similar to natural cells and are capable of regeneration.Preparation of cell aggregates is one of the important steps in 3D tissue engineering technology,particularly in organ printing.Two simple methods,hanging drop(HD)and conical tube(CT)were utilized to prepare cell aggregates.The size and viability of the aggregates obtained at different initial cell densities and pre-culture duration were compared.The proliferative ability of the cell aggregates and their ability to spread in culture plates were also investigated.In both methods,the optimum average size of the aggregates was less than 500μm.CT aggregates were smaller than HD aggregates.5,000 cells per drop HD aggregates showed a marked ability to attach and spread on the culture surface.The proliferative ability reduced when the initial cell density was increased.Comparing these methods,we found that the HD method having better size controlling ability as well as enhanced ability to maintain higher rates of viability,spreading,and proliferation.In conclusion,smaller HD aggregates might be a suitable choice as building blocks for making bioink particles in bioprinting technique.
基金Supported by a grant from Tehran University of Medical Science, No. 11250 (in part)
文摘AIM: To study the combinative effects of nanocerium and selenium in a murine model of diabetes. METHODS: Cerium oxide (CeO2) nanoparticles (60 mg/kg per day) and sodium selenite (5 μmol/kg per day) aloneor in combination, or the metal form of CeO2 (60 mg/kg) were administered for 2 wk by intraperitoneal injection to streptozotocin-induced diabetic rats. At the end of treatment blood was collected, liver tissue dissected and then oxidative stress markers, extent of energy depletion and lipid prof ile were evaluated.RESULTS: Antioxidant enzymes and high density lipoprotein decreased whereas oxidative stress, adenosine diphosphate/adenosine triphospahte levels, cholesterol, triglyceride and low density lipoprotein increased on induction of diabetes. All were improved by a combination of nanocerium and sodium selenite. There was a relative amelioration by CeO2 nanoparticles or sodium selenite alone, but the metal form of CeO2 showed no signif icant improvement. CONCLUSION: The combination of nanocerium and sodium selenite is more effective than either alone in improving diabetes-induced oxidative stress.
