The grain refinement of the as-cast AZ31 alloys by limestone particles was investigated by grain refining tests and microstructure observations. The results show that the limestone particles have a good grain refining...The grain refinement of the as-cast AZ31 alloys by limestone particles was investigated by grain refining tests and microstructure observations. The results show that the limestone particles have a good grain refining potency, which is deeply related to the addition level of limestone and melting temperature. The optimal addition level and melting temperature are 2.0%(mass fraction) and 720 ℃, respectively. The average grain size of AZ31 alloy is reduced from(556±60) to(236±22) μm. The sound grain refining by raw limestone particles has a good anti-fading capacity without any significant grain coarsening in a 40 min holding time. The concerned grain refining mechanism should be attributed to the inoculated Al-C and Al-C/Al-Mn-(Fe) nuclei. Ultrasonic treatment can enhance the grain refining efficiency of limestone particles through cavitation-enhanced nucleation mechanism.展开更多
Objective:To investigate the role of macrophages in regulating breast cancer cell migration and its related mechanisms.Methods:Human leukemia monocytic cell line THP-1-secreted exosomes were isolated using multi-step ...Objective:To investigate the role of macrophages in regulating breast cancer cell migration and its related mechanisms.Methods:Human leukemia monocytic cell line THP-1-secreted exosomes were isolated using multi-step ultracentrifugation and verified using nanoparticle tracking analysis.Differentially expressed miRNAs were identified using RNA sequencing.Overexpression of inhibitors of hsa-miR-101-3p in breast cancer MDA-MB-231 cells was performed by infecting their lentiviral constructs.The luciferase reporter assay was used to evaluate the interaction of DLG5 and miR-101.DGL5 expression was detected using qRT-PCR and Western blot analyses.Results:The migration of breast cancer cells was significantly inhibited after addition of exosomes.RNA sequencing results showed that miR-101-3p expression was significantly upregulated.Targetscan analysis predicted that miR-101-3p could target DLG5,and this prediction was verified using the luciferase assay.The addition of the miR-101-3p precursor significantly increased the expression of miR-101-3p,and the mRNA and protein levels of DLG5 were suppressed.In contrast,inhibiting the expression of miR-101-3p increased the mRNA and protein levels of DLG5.Furthermore,the scratch assay showed that inhibiting miR-101-3p could promote the migration of MDA-MB-231 cells.Conclusions:Macrophage exosomes can inhibit the migration of breast cancer cells,and increasing the expression of miR-101-3p to inhibit DLG5 expression may play an important role in this process,which needs further investigation.展开更多
基金Project(2016YFB0301104)supported by National Key Research and Development Program of China
文摘The grain refinement of the as-cast AZ31 alloys by limestone particles was investigated by grain refining tests and microstructure observations. The results show that the limestone particles have a good grain refining potency, which is deeply related to the addition level of limestone and melting temperature. The optimal addition level and melting temperature are 2.0%(mass fraction) and 720 ℃, respectively. The average grain size of AZ31 alloy is reduced from(556±60) to(236±22) μm. The sound grain refining by raw limestone particles has a good anti-fading capacity without any significant grain coarsening in a 40 min holding time. The concerned grain refining mechanism should be attributed to the inoculated Al-C and Al-C/Al-Mn-(Fe) nuclei. Ultrasonic treatment can enhance the grain refining efficiency of limestone particles through cavitation-enhanced nucleation mechanism.
基金supported by the Key Research and Development Program of Hainan Province(ZDYF2020139,ZDYF2018158)the Science and Technology Funding Project of Hainan Province(821MS129).
文摘Objective:To investigate the role of macrophages in regulating breast cancer cell migration and its related mechanisms.Methods:Human leukemia monocytic cell line THP-1-secreted exosomes were isolated using multi-step ultracentrifugation and verified using nanoparticle tracking analysis.Differentially expressed miRNAs were identified using RNA sequencing.Overexpression of inhibitors of hsa-miR-101-3p in breast cancer MDA-MB-231 cells was performed by infecting their lentiviral constructs.The luciferase reporter assay was used to evaluate the interaction of DLG5 and miR-101.DGL5 expression was detected using qRT-PCR and Western blot analyses.Results:The migration of breast cancer cells was significantly inhibited after addition of exosomes.RNA sequencing results showed that miR-101-3p expression was significantly upregulated.Targetscan analysis predicted that miR-101-3p could target DLG5,and this prediction was verified using the luciferase assay.The addition of the miR-101-3p precursor significantly increased the expression of miR-101-3p,and the mRNA and protein levels of DLG5 were suppressed.In contrast,inhibiting the expression of miR-101-3p increased the mRNA and protein levels of DLG5.Furthermore,the scratch assay showed that inhibiting miR-101-3p could promote the migration of MDA-MB-231 cells.Conclusions:Macrophage exosomes can inhibit the migration of breast cancer cells,and increasing the expression of miR-101-3p to inhibit DLG5 expression may play an important role in this process,which needs further investigation.