Background:The JAK2^(V617F)mutation plays a crucial part in the pathogenesis of myeloproliferative neoplasms(MPN),which includes polycythemia vera(PV),essential thrombocythemia(ET),and primary myelofibrosis(PMF)leadin...Background:The JAK2^(V617F)mutation plays a crucial part in the pathogenesis of myeloproliferative neoplasms(MPN),which includes polycythemia vera(PV),essential thrombocythemia(ET),and primary myelofibrosis(PMF)leading to aberrant proliferation and survival of hematopoietic cells.Alongside the challenges of drug resistance and side effects,identifying novel compounds that selectively target JAK2^(V617F)could provide more effective and safer therapeutic options for patients with MPNs.Materials and Methods:We employed computational approaches like high-throughput virtual screening,molecular dynamics simulations(MDS),and binding free energy calculations to identify inhibitors targeting wild and mutant JAK2 kinases.JAK2^(V617F)positive HEL,wild type JAK2 positive TF-1,and non-cancerous Vero cells were used for in vitro validations.Results:SBLJ23 emerged as a top candidate inhibitor with specificity for JAK2^(V617F).Protein-ligand interaction studies and MDS revealed stable interactions and binding of SBLJ23 over the simulation period,with Root Mean Square Deviation(RMSD)indicating consistent binding after 1t15ns.SBLJ23 displayed a half maximal inhibitory concentration(IC_(50))value of 522.4 nM against the JAK2 enzyme.The compound exhibited inhibition of cell proliferation in HEL and TF-1 cells,with half maximal cell growth inhibitory concentration(GI 50)values of 2.51 and 15.87μM,respectively.Moreover,SBLJ23 induced G 2/M cell cycle arrest in HEL cells to facilitate apoptosis in these cell lines.The compound significantly reduced the percentage of phospho JAK2 and phospho STAT3 in HEL cells.Conclusion:High binding affinity,stable interaction profile,favorable binding free energy,and in vitro validations claim SBLJ23 as a potential lead compound against JAK2^(V617F)and suggest further development and optimization towards clinical application in managing myeloproliferative neoplasms.展开更多
The microstructure and mechanical properties of alloy 617 B in the process of 5000 h aging at 750 °C were systematically investigated by means of SEM, TEM and mechanical analysis. M23C6 particles were dispersed i...The microstructure and mechanical properties of alloy 617 B in the process of 5000 h aging at 750 °C were systematically investigated by means of SEM, TEM and mechanical analysis. M23C6 particles were dispersed inside grains and distributed discontinuously along grain boundaries and γ′ phases were situated at intragranular sites in the process of aging. The size of precipitates increased with increasing aging time. Inter- and intra-granular carbide and γ′ phase particles inside grains resulted in the precipitation strengthening of this aged alloy, enhancing the strength and hardness. The aged alloy possessed good stabilities of hardness and strength during aging. An obvious decrease of the toughness of this aged alloy was due to γ′ phase particles limiting plastic deformation to the area nearby grain boundaries, resulting in the occurrence of crack along grain boundaries. Additionally, the intergranular cracks apparently led to a decrease in the toughness for this aged alloy due to carbide particles at grain boundaries. The toughness of this aged alloy was fairly stable possibly due to the unchanged distribution of the precipitates during aging.展开更多
文摘Background:The JAK2^(V617F)mutation plays a crucial part in the pathogenesis of myeloproliferative neoplasms(MPN),which includes polycythemia vera(PV),essential thrombocythemia(ET),and primary myelofibrosis(PMF)leading to aberrant proliferation and survival of hematopoietic cells.Alongside the challenges of drug resistance and side effects,identifying novel compounds that selectively target JAK2^(V617F)could provide more effective and safer therapeutic options for patients with MPNs.Materials and Methods:We employed computational approaches like high-throughput virtual screening,molecular dynamics simulations(MDS),and binding free energy calculations to identify inhibitors targeting wild and mutant JAK2 kinases.JAK2^(V617F)positive HEL,wild type JAK2 positive TF-1,and non-cancerous Vero cells were used for in vitro validations.Results:SBLJ23 emerged as a top candidate inhibitor with specificity for JAK2^(V617F).Protein-ligand interaction studies and MDS revealed stable interactions and binding of SBLJ23 over the simulation period,with Root Mean Square Deviation(RMSD)indicating consistent binding after 1t15ns.SBLJ23 displayed a half maximal inhibitory concentration(IC_(50))value of 522.4 nM against the JAK2 enzyme.The compound exhibited inhibition of cell proliferation in HEL and TF-1 cells,with half maximal cell growth inhibitory concentration(GI 50)values of 2.51 and 15.87μM,respectively.Moreover,SBLJ23 induced G 2/M cell cycle arrest in HEL cells to facilitate apoptosis in these cell lines.The compound significantly reduced the percentage of phospho JAK2 and phospho STAT3 in HEL cells.Conclusion:High binding affinity,stable interaction profile,favorable binding free energy,and in vitro validations claim SBLJ23 as a potential lead compound against JAK2^(V617F)and suggest further development and optimization towards clinical application in managing myeloproliferative neoplasms.
基金Project(2012AA050501)supported by the National High-tech Research and Development Program of ChinaProject(NY20110102)supported by the National Energy Applied Technology and Engineering Demonstration Program,China+1 种基金Project(2012CB724401)supported by the National Basic Research Program of ChinaProject(003)supported by CSEE Youth Science & Technology Innovation,China
文摘The microstructure and mechanical properties of alloy 617 B in the process of 5000 h aging at 750 °C were systematically investigated by means of SEM, TEM and mechanical analysis. M23C6 particles were dispersed inside grains and distributed discontinuously along grain boundaries and γ′ phases were situated at intragranular sites in the process of aging. The size of precipitates increased with increasing aging time. Inter- and intra-granular carbide and γ′ phase particles inside grains resulted in the precipitation strengthening of this aged alloy, enhancing the strength and hardness. The aged alloy possessed good stabilities of hardness and strength during aging. An obvious decrease of the toughness of this aged alloy was due to γ′ phase particles limiting plastic deformation to the area nearby grain boundaries, resulting in the occurrence of crack along grain boundaries. Additionally, the intergranular cracks apparently led to a decrease in the toughness for this aged alloy due to carbide particles at grain boundaries. The toughness of this aged alloy was fairly stable possibly due to the unchanged distribution of the precipitates during aging.