Phase transition and critical properties of spin-orbital interacting systems

Phase transition and critical properties of Ising-like spin-orbital interacting systems in 2-dimensional triangular lattice are investigated. We first show that the ground state of the system is a composite spin-orbital ferro-ordered phase. Though Landau effective field theory predicts the second-order phase transition of the composite spin-orbital order, however, the critical exponents obtained by the renormalization group approach demonstrate that the spin-orbital order-disorder transition is far from the second-order, rather, it is more close to the first-order, implying that the widely observed first-order transition in many transition-metal oxides may be intrinsic. The unusual critical behavior near the transition point is attributed to the fractionalization of the composite order parameter.Comment: Accepted to Phys. Lett.

NF-κB-Regulated miR-99a Modulates Endothelial Cell Inflammation

Objective. The present study was performed to investigate the effects and mechanisms of miR-99a on LPS-induced endothelial cell inflammation, as well as the regulation of NF-κB on miR-99a production. Methods and Results. ELISA showed that LPS treatment significantly promoted the secretion of inflammatory factors (TNF-α, IL-6, IL-1β, and MCP-1). LPS treatment also inhibited miR-99a production and promoted mTOR expression and NF-κB nuclear translocation. Overexpression of miR-99a suppressed the LPS-induced TNF-α, IL-6, IL-1β, and MCP-1 overproduction, mTOR upregulation, and NF-κB nuclear translocation. The PROMO software analysis indicated NF-κB binding site in the −1643 to −1652 region of miR-99a promoter. Dual luciferase reporter analysis, electrophoretic mobility shift assays (EMSA), and chromosome immunoprecipitation (ChIP) assays demonstrated that NF-κB promoted the transcription of miR-99a by binding to the −1643 to −1652 region of miR-99a promoter. Further studies on HUVECs verified the regulatory effects of NF-κB on miR-99a production. Conclusion. MiR-99a inhibited the LPS-induced HUVECs inflammation via inhibition of the mTOR/NF-κB signal. NF-κB promoted miR-99a production by binding to the −1643 to −1652 region of miR-99a promoter. Considering the importance of endothelial inflammation on cardiovascular diseases, such as atherosclerosis, our results may provide a new insight into the pathogenesis and therapy of atherosclerosis

Meta-Analysis for the Association between Polymorphisms in Interleukin-17A and Risk of Coronary Artery Disease

Coronary artery disease (CAD) is a disease which has become a leading cause of death worldwide. The polymorphisms in Interleukin-17 (IL-17A), including rs2275913, rs3819024, rs3819025, rs3748067, rs8193037, rs4711998, and rs8193036, have been found to be probably associated with the risk of CAD. However, the results were inconsistent and inconclusive. The present study performed a meta-analysis to get a more precise and comprehensive estimation of the association between the IL-17A polymorphisms and CAD risk. The Pubmed, Embase, Cochrane Central Register of Controlled Trials, Chinese National Knowledge Infrastructure, and Chinese Biomedical Literature Databases were searched for related studies. A total of six studies, including 3542 cases and 3212 controls, were identified for the meta-analysis. The main findings of the present meta-analysis show that the TT genotype of IL-17A rs3748067 is associated with a significant lower risk of CAD in the homozygous model odds ratio (OR) (OR = 0.37) in Asians. No significant association was found for rs2275913, rs3819024, rs3819025, rs8193037, rs4711998, and rs8193036 with CAD susceptibility in the overall analysis. However, subgroup analysis indicated a significant decreased risk of CAD for the GG genotype and G allele of rs2275913 in a small sample size group, and a higher risk of CAD for the GG genotype and G allele of rs8193037 in a heterozygous model (OR = 1.56), dominant model (OR = 1.54), and allelic model (OR = 1.47) in Asians. In conclusion, the current meta-analysis suggests a significant relationship between rs3748067, rs8193037, and CAD in Asians, while for rs2275913, rs3819024, rs3819025, rs4711998, rs8193036, no such relations were found. Thus, IL-17A rs3748067 and rs8193037 might be recommended as a predictor for susceptibility of CAD for Asians. However, the results of this meta-analysis are hypothesis-generating results which should be interpreted with caution because of the heterogeneity and publication bias among study designs

Neurogenin 2 Converts Mesenchymal Stem Cells into a Neural Precursor Fate and Improves Functional Recovery after Experimental Stroke

Background: Neurogenin2 (Ngn2) is a proneural gene that directs neuronal differentiation of progenitor cells during development. Here, we investigated whether Ngn2 can reprogram MSCs to adopt a neural precursor fate and enhance the therapeutic effects of MSCs after experimental stroke. Methods: In vitro, MSCs were transfected with lenti-GFP or lenti-Ngn2. Following neuronal induction, cells were identified by immunocytochemistry, Western blot and electrophysiological analyses. In a stroke model induced by transient right middle cerebral artery occlusion (MCAO), PBS, GFP-MSCs or Ngn2-MSCs were injected 1 day after MCAO. Behavioral tests, neurological and immunohistochemical assessments were performed. Results: In vitro, Ngn2-MSCs expressed neural stem cells markers (Pax6 and nestin) and lost the potential to differentiate into mesodermal cell types. Following neural induction, Ngn2-MSCs expressed higher levels of neuron-specific proteins MAP2, Tuj1 and NeuN, and also expressed voltage-gated Na+ channel, which was absent in GFP-MSCs. In vivo, after transplantation, Ngn2-MSCs significantly reduced apoptotic cells, decreased infarct volume, and increased the expression of VEGF and BDNF. Finally, Ngn2-MSCs treated animals showed the highest functional recovery among the three groups. Conclusions: Ngn2 was sufficient to convert MSCs into a neural precursor fate and transplantation of Ngn2-MSCs was advantageous for the treatment of stroke rats