HSA-MIR-203/MyD88 axis mediates the protective effect of hispidulin on LPS-induced apoptosis in a human renal tubular epithelial line,HK-2

Acute kidney injury(AKI),commonly occurring as complications of sepsis,cardiac surgery,and liver or kidney transplantation,is a critical care syndrome.It is well known that lipopolysaccharide(LPS)shock is a common triggering factor for AKI.This study is aimed to examine the effect of flavonoid compound hispidulin on LPS-induced AKI.For this,renal tubular epithelial cell HK-2 was treated with LPS to establish an in vitro model of AKI.The effect of hispidulin on HK-2 cell viability was examined using CCK-8 assay.Cell apoptosis was determined by TUNEL and flow cytometry.Apoptosis marker proteins were determined by using western blot.The levels of pro-inflammatory cytokines were determined by ELISA assay and qRT-PCR.The translocation of NF-κB was determined by western blot.The effect of MyD88 on the cytoprotective activities of hispidulin was examined by overexpressing MyD88 in HK-2 cells.Our results showed that hispidulin was not able to produce a cytotoxic effect on HK-2 cells at tested concentrations.However,hispidulin could protect HK-2 cells from LPS-induced cell injury.Our results also showed that hispidulin was able to attenuate LPS-induced HK-2 cell apoptosis.In addition,LPS led to an inflammatory response in HK-2 cells,evidenced by NF-κB p65 activation as well as increased expression and release of inflammatory cytokine IL-6 and TNF-α,which could be reversed by pretreatment with hispidulin.Overexpression MyD88 was found to significantly dampen the cytoprotective activities of hispidulin against LPS insult.More importantly,MyD88 was identified as a direct target of hsa-miR-203,and hispidulin was found to regulate the expression of MyD88 via upregulating hsa-miR-203.Our results showed that hispidulin attenuates LPS-induced HK-2 damage via regulating hsa-miR-203/MyD88 axis.

High cerium content(Nd-Pr-Ce)_(2)Fe_(14)B melt-spun ribbons with high coercivity

The effects of wheel speeds on the magnetic properties and microstructures of[(Nd,Pr)_(1-x)Ce_(x)]-Fe-B meltspun ribbons were investigated.Compared to melt-spun ribbons with low cerium(Ce)content(x=0.2),amorphous formation can be suppressed at high wheel speed in the ribbons with a relatively high Ce content(x=0.8),and with the increase of the wheel speed,the magnetic properties of the ribbons with high Ce content raise continuously.At high wheel speed,the coercivity mechanism of melt-spun ribbons is mainly pinning field,and the high wheel speed introduces a large number of defects into the matrix as pinning sites.Furthermore,ribbons with high Ce content form a fine and uniform grain structure,so the grain boundary area enlarges,which further hinders the movement of domain walls.The combined effects of the above factors enable ribbons with high Ce content to have excellent magnetic properties(Hcj=0.977 T,Mr=64 m^(2) A/kg)at the wheel speed of 35 m/s.

Flat-band ferromagnetism of SU(N) Hubbard model on Tasaki lattices

We investigate the para-ferro magnetic transition of the repulsive SU(N) Hubbard model on a type of oneand two-dimensional decorated cubic lattices, referred as Tasaki lattices, which feature massive singleparticle ground state degeneracy. Under certain restrictions for constructing localized many-particle ground states of flat-band ferromagnetism, the quantum model of strongly correlated electrons is mapped to a classical statistical geometric site-percolation problem, where the nontrivial weights of different configurations must be considered. We prove rigorously the existence of para-ferro transition for the SU(N) Hubbard model on one-dimensional Tasaki lattice and determine the critical density by the transfer-matrix method. In two dimensions, we numerically investigate the phase transition of SU(3),SU(4) and SU(10) Hubbard models by Metropolis Monte Carlo simulation. We find that the critical density exceeds that of standard percolation, and increases with spin degrees of freedom, implying that the effective repulsive interaction becomes stronger for larger N. We further rigorously prove the existence of flat-band ferromagnetism of the SUeNT Hubbard model when the number of particles equals to the degeneracy of the lowest band in the single-particle energy spectrum.