Aims T-type Ca<sup>2+</sup> current(I<sub>CaT</sub>)plays an important role in the pathogenesis of atrial fibrillation（AF）.The present study sought to investigate the role of Macrophage migra...Aims T-type Ca<sup>2+</sup> current(I<sub>CaT</sub>)plays an important role in the pathogenesis of atrial fibrillation（AF）.The present study sought to investigate the role of Macrophage migration inhibitory factor（MIF）,a pleiotropic cytokine,in the regulation of T-type Ca<sup>2+</sup> channel in atrium myocytes.Methods We used whole-cell voltage-clamp technique and biochemical assays to study the regulation and expression of I<sub>Ca</sub>,T in mouse atrium myocytes（HL-1 cells）.Results Serum MIF concentrations was slightly increased in patients with AF compared to sinus rhythm（SR） controls.In cultured HL-1 cells, significant amounts of MIF were produced in response to hydrogen peroxide（H<sub>2</sub>O<sub>2</sub>）,but not AngiotensinⅡ（AngⅡ）. Mouse recombinant MIF（rMIF）（20 or 40 nM,24 h） suppressed peak ICa,T by-38%and-60%in a concentration-dependent manner,impaired the voltage-dependent activation of I<sub>Ca</sub>,T,and down-regulated of TCC alG mRNA.Src inhibitors genistein and PPl significantly enhanced ICaT.The depression of ICa,T induced by rMIF could be reversed by genistein and PP1.Conclusions MIFis involved in the pathogenesis of AF,probably by decreasing ICa,T through impairment of the channel function and activation of c-Src kinases in atrium myocytes.展开更多
The honey badger algorithm(HBA),as a new swarm intelligence(SI)optimization algorithm,has shown certain effectiveness in its applications.Aiming at the problems of unsatisfactory initial population distribution of HBA...The honey badger algorithm(HBA),as a new swarm intelligence(SI)optimization algorithm,has shown certain effectiveness in its applications.Aiming at the problems of unsatisfactory initial population distribution of HBA,poor ability to avoid local optimum,and slow convergence speed,this paper proposes a multi-strategy improved HBA based on periodical mutation and t-distribution perturbation,called MHBA.Firstly,a good point set population initialization is introduced to get a uniform initial population.Secondly,periodic mutation and t-distribution perturbation are successively used to improve the algorithm’s ability to avoid local optimum.Finally,the density factor is improved for balancing exploration and exploitation.By comparing MHBA with HBA and 7 other SIs on 6 benchmark functions,it is evident that the performance of MHBA is far superior to HBA.In addition,by applying MHBA to robot path planning,MHBA can identify the shortest path more quickly and consistently compared with competitors.展开更多
文摘Aims T-type Ca<sup>2+</sup> current(I<sub>CaT</sub>)plays an important role in the pathogenesis of atrial fibrillation（AF）.The present study sought to investigate the role of Macrophage migration inhibitory factor（MIF）,a pleiotropic cytokine,in the regulation of T-type Ca<sup>2+</sup> channel in atrium myocytes.Methods We used whole-cell voltage-clamp technique and biochemical assays to study the regulation and expression of I<sub>Ca</sub>,T in mouse atrium myocytes（HL-1 cells）.Results Serum MIF concentrations was slightly increased in patients with AF compared to sinus rhythm（SR） controls.In cultured HL-1 cells, significant amounts of MIF were produced in response to hydrogen peroxide（H<sub>2</sub>O<sub>2</sub>）,but not AngiotensinⅡ（AngⅡ）. Mouse recombinant MIF（rMIF）（20 or 40 nM,24 h） suppressed peak ICa,T by-38%and-60%in a concentration-dependent manner,impaired the voltage-dependent activation of I<sub>Ca</sub>,T,and down-regulated of TCC alG mRNA.Src inhibitors genistein and PPl significantly enhanced ICaT.The depression of ICa,T induced by rMIF could be reversed by genistein and PP1.Conclusions MIFis involved in the pathogenesis of AF,probably by decreasing ICa,T through impairment of the channel function and activation of c-Src kinases in atrium myocytes.
基金Supported by the National Key Research and Development Program of China(No.2022ZD0119001)。
文摘The honey badger algorithm(HBA),as a new swarm intelligence(SI)optimization algorithm,has shown certain effectiveness in its applications.Aiming at the problems of unsatisfactory initial population distribution of HBA,poor ability to avoid local optimum,and slow convergence speed,this paper proposes a multi-strategy improved HBA based on periodical mutation and t-distribution perturbation,called MHBA.Firstly,a good point set population initialization is introduced to get a uniform initial population.Secondly,periodic mutation and t-distribution perturbation are successively used to improve the algorithm’s ability to avoid local optimum.Finally,the density factor is improved for balancing exploration and exploitation.By comparing MHBA with HBA and 7 other SIs on 6 benchmark functions,it is evident that the performance of MHBA is far superior to HBA.In addition,by applying MHBA to robot path planning,MHBA can identify the shortest path more quickly and consistently compared with competitors.
