In this study, the corrosion behavior of Ni47Ti49Co4 shape memory alloy（SMA） was investigated in simulated saliva solution with the binary alloy Ni（51）Ti49 as a reference. The surface morphology and the chemical c...In this study, the corrosion behavior of Ni47Ti49Co4 shape memory alloy（SMA） was investigated in simulated saliva solution with the binary alloy Ni（51）Ti49 as a reference. The surface morphology and the chemical composition of the oxide films were characterized by scanning electron microscopy and X-ray photoelectron spectroscopy before and after immersion in the test solutions, respectively. The results showed that the ternary alloy was less affected by the test solution,owning to the formation of passive layer composed mainly of the oxides of titanium and cobalt in several oxidation states.Cyclic voltammetry, electrochemical impedance spectroscopy and potentiodynamic polarization measurements affirmed that the passive oxide film significantly improved the corrosion resistance of Ni47Ti49Co4 SMAs as demonstrated by the smaller corrosion current density, larger resistance and smaller capacitance. Consequently, alloying with cobalt, which has paramount importance in enhancing the passive layer, expands the use of Ni47Ti49Co4 SMAs in dental work as new nitinol alloys with high corrosion resistances.展开更多
Background:The breast cancer has been the most common form of cancer among women.The triple negative subtype represents 20%of all breast cancer cases in the world and is standing out by affecting young women and being...Background:The breast cancer has been the most common form of cancer among women.The triple negative subtype represents 20%of all breast cancer cases in the world and is standing out by affecting young women and being aggressive.The main cause of death of patients with cancer is due to metastasis,which can reach the liver and lungs.Objective:The activities of ID7 fraction of the stems of Bauhinia variegata L.on breast cancer,lung metastasis and liver inflammatory process were evaluated.Method:ID7 was characterized by mass-spectrometry.The viability of murine mammary cells(4T1)treated with ID7 was assessed by MTT,trypan blue and fluorescence assay and viability of BT-20,MDA-MB-231 and MCF-7 human breast cancer tumor lines by MTS.The cell migration,invasion using matrigel and adhesion were performed.The expression of cell death proteins was quanitified by western blot and the gelatinases by zimogram.The ID7 activity of the tumor(4T1)and metastatic progession in vivo was evaluated.Results:ID7 reduced the 4T1 and MDA-MB-231viability and increased the late apoptosis,inhibited the 4T1 migration and invasion,increased the 4T1 adhesion and decreased the secreted active gelatinases.ID7 also increased the expression of PARP,caspase-7 and caspase-8,RIP and TNF-R1.In vivo,the ID7 decreased the volume and weight of the tumors and decreased lung metastasis and inflammation in the liver.The characterization showed mainly the presence of oleic acid,myricetin,quercetin and kaempferol in ID7.Conclusion:Thus,it was found that ID7 fraction exhibits selective antitumor and on the mechanisms of breast cancer metastasis activity,preventing lung metastasis and inflammation in the liver.It is suggested that fatty acids and flavonoids are correlated with such activities.展开更多
基金the financial support of Chemistry Department (Taif University, Saudi Arabia)
文摘In this study, the corrosion behavior of Ni47Ti49Co4 shape memory alloy（SMA） was investigated in simulated saliva solution with the binary alloy Ni（51）Ti49 as a reference. The surface morphology and the chemical composition of the oxide films were characterized by scanning electron microscopy and X-ray photoelectron spectroscopy before and after immersion in the test solutions, respectively. The results showed that the ternary alloy was less affected by the test solution,owning to the formation of passive layer composed mainly of the oxides of titanium and cobalt in several oxidation states.Cyclic voltammetry, electrochemical impedance spectroscopy and potentiodynamic polarization measurements affirmed that the passive oxide film significantly improved the corrosion resistance of Ni47Ti49Co4 SMAs as demonstrated by the smaller corrosion current density, larger resistance and smaller capacitance. Consequently, alloying with cobalt, which has paramount importance in enhancing the passive layer, expands the use of Ni47Ti49Co4 SMAs in dental work as new nitinol alloys with high corrosion resistances.
文摘Background:The breast cancer has been the most common form of cancer among women.The triple negative subtype represents 20%of all breast cancer cases in the world and is standing out by affecting young women and being aggressive.The main cause of death of patients with cancer is due to metastasis,which can reach the liver and lungs.Objective:The activities of ID7 fraction of the stems of Bauhinia variegata L.on breast cancer,lung metastasis and liver inflammatory process were evaluated.Method:ID7 was characterized by mass-spectrometry.The viability of murine mammary cells(4T1)treated with ID7 was assessed by MTT,trypan blue and fluorescence assay and viability of BT-20,MDA-MB-231 and MCF-7 human breast cancer tumor lines by MTS.The cell migration,invasion using matrigel and adhesion were performed.The expression of cell death proteins was quanitified by western blot and the gelatinases by zimogram.The ID7 activity of the tumor(4T1)and metastatic progession in vivo was evaluated.Results:ID7 reduced the 4T1 and MDA-MB-231viability and increased the late apoptosis,inhibited the 4T1 migration and invasion,increased the 4T1 adhesion and decreased the secreted active gelatinases.ID7 also increased the expression of PARP,caspase-7 and caspase-8,RIP and TNF-R1.In vivo,the ID7 decreased the volume and weight of the tumors and decreased lung metastasis and inflammation in the liver.The characterization showed mainly the presence of oleic acid,myricetin,quercetin and kaempferol in ID7.Conclusion:Thus,it was found that ID7 fraction exhibits selective antitumor and on the mechanisms of breast cancer metastasis activity,preventing lung metastasis and inflammation in the liver.It is suggested that fatty acids and flavonoids are correlated with such activities.
