Valence Fluctuation of Uranium Ions in Uranium Sesquinitride Revealed by Dynamical Mean-field Theory Merged with Density Functional Theory.

The electronic properties, in particular, the occupation number of 5f electrons and the valence state of U ions in uranium sesquinitride (U2 N3 ) are studied by using density functional theory (DFT) calculations merged with dynamical mean-field theory (DMFT). The results demonstrate that j=5/2 and j=7/2 manifolds are in the weakly correlated metallic and weakly correlated insulating regimes, respectively. The quasi-particle weights indicate that LS coupling scheme is more feasible for 5f electrons, which are not in the orbital-selective localized state. The weighted summation of the occupation probabilities of 5fn (n=0,1,2,3,4) atomic configurations suggests that 5f electrons have the inter-configuration fluctuation, or the mixed-valence state for U ions, together with an average occupation number of 5f electrons n5f ∼2.234, which is in good agreement with the electron localization function (ELF) and occupation analysis based on other DFT-based calculations. The 5fn -mixing-driven inter-configuration fluctuation might originate from the dual nature of 5f electrons, and the flexible electronic configuration of U ions. Finally, the so-called quasiparticle band structure is also discussed.

Advanced glycation end products induce chemokine/cytokine production via activation of p38 pathway and inhibit proliferation and migration of bone marrow mesenchymal stem cells.

BACKGROUND: Advanced glycation products (AGEs), as endogenous inflammatory mediator, compromise the physiological function of mesenchymal stem cells (MSCs). MSCs have a potential role in cell replacement therapy in acute myocardial infarction and ischemic cardiomyopathy. However, mechanisms of AGEs on MSCs are still not unveiled. METHODS: Reactive oxygen species (ROS), genes regulation, cell proliferation and migration have been detected by AGE-BSA stimulated MSCs. RESULTS: We found that in vitro stimulation with AGE-BSA induced generation of reactive oxygen species (ROS), and inhibited dose-dependently proliferation and migration of MSCs. Microarray and molecular biological assessment displayed an increased expression and secretion of Ccl2, Ccl3, Ccl4 and Il1b in a dose- and time-dependent manner. These chemokines/cytokines of equivalent concentration to those in conditioned medium exerted an inhibitory effect on MSC proliferation and migration after stimulation for 24 h. Transient elevation of phospho-p38 in MSCs upon AGE-BSA stimulation was blocked with p38 inhibitor. CONCLUSIONS: The study indicates that AGE-BSA induces production of chemokines/cytokines in a dose- and time-dependent manner via activation of ROS-p38 mediated pathway. These chemokines/cytokines exert an inhibitory effect on MSC growth and migration, suggesting an amplified dysfunction of MSCs by AGEs.

Benefit of initial dual-therapy on stroke prevention in Chinese hypertensive patients: a real world cohort study.

AIMS: Studies have shown that combination anti-hypertensive therapy is superior to mono-therapy in blood pressure control and prevention of cardiovascular events. However, whether such advantage exists in the prevention of stroke in Chinese hypertensive patients remains unclear. This study aimed to compare the impact of initial combination versus mono-therapy on stroke events in a large cohort of Chinese hypertensive patients. METHODS AND RESULTS: Hypertensive patients with uncontrolled blood pressure and without a history of stroke were screened from the Shanghai Community-dwelling Hypertensive Population Follow-up Database. Based on the initial treatment, individuals were divided into an initial mono-therapy group and initial dual combination group. Patients were followed for 42 months. 32,682 and 4,926 patients were included in the initial mono- and dual-therapy group. The achieved target blood pressure control rates of mono vs. combination groups at 6, 12, 24, and 42 months of follow-up, were 59.47% vs. 60.05%, 78.23% vs. 77.06%, 85.51% vs. 84.02%, and 86.90% vs. 85.44%, respectively. Their corresponding incidence densities of stroke were 0.792 vs. 0.489, 1.49 vs. 1.15, 2.79 vs. 2.38, and 4.25 vs. 4.32 (cases per 100 person-year), respectively. The 6-month incidence of stroke in dual-therapy group was significantly lower than mono-therapy group (adjusted HR 0.64; 95% CI: 0.30-0.93). However, no significant group differences in the incidence density were observed at 12, 24, and 42 months. CONCLUSIONS: Our study demonstrates that, for patients with uncontrolled hypertension, initial dual therapy is more effective in the prevention of stroke during the first 6 months of treatment, but not thereafter. Combination antihypertensive therapy may be a beneficial initial strategy for early stroke prevention.

The prognostic value of long-term visit-to-visit blood pressure variability on stroke in real-world practice: a dynamic cohort study in a large representative sample of Chinese hypertensive population.

BACKGROUND: The prognostic significance of long-term visit-to-visit blood pressure variability (BPV) has not yet been validated in "real world" hypertensive patients. The aim of the current study is to explore the prognostic value of BPV on stroke in hypertensive patients. METHODS: This was a dynamic prospective cohort study based on electronic medical records in Shanghai, China. Hypertensive patients (N=122,636) without history of stroke at baseline, were followed up from 2005 to 2011. The cohort comprised of 4522 stroke patients and 118,114 non-stroke patients during a mean follow-up duration of 48 months. BPV was measured by standard deviation (SD) and the coefficient of variation (CV) of blood pressure. RESULTS: The visit-to-visit variability of both systolic blood pressure (SBP) and diastolic blood pressure (DBP) was independently associated with the occurrence of stroke [SD: the hazard ratios (95% confidence intervals) of SBP and DBP were 1.042 (1.021 to 1.064) and 1.052 (1.040 to 1.065); CV: the hazard ratios (95% confidence intervals) of SBP and DBP were 1.183 (1.010 to 1.356) and 1.151 (1.005 to 1.317), respectively]. The hazard ratio values increased along with an increase of the BPV levels of SBP and DBP. The increment effect remained significant after controlling the blood pressure control status of subjects. CONCLUSIONS: Increased BPV of both SBP and DBP, independent of the average blood pressure, is a predictor of stroke among community hypertensive patients in real-world clinical practice. The risk of stroke increased along with increased BPV. Stabilizing BPV might be a therapeutic target in hypertension.

Valsartan/amlodipine compared to nifedipine GITS in patients with hypertension inadequately controlled by monotherapy.

INTRODUCTION: Current hypertension guidelines recommend single-pill combinations because they not only improve convenience and compliance to therapy and thus blood pressure (BP) control, but also reduce health-care costs. This study compared the efficacy and safety of valsartan/amlodipine single-pill combination with nifedipine gastrointestinal therapeutic system (GITS) in Chinese patients with hypertension who were inadequately controlled with monotherapy. METHODS: In this multicenter, open-label, active-controlled, parallel-group study, 564 patients with hypertension not adequately controlled by prior monotherapy were randomized to receive valsartan/amlodipine 80/5 mg or nifedipine GITS 30 mg once daily for 12 weeks. RESULTS: In the intention-to-treat analysis (n = 540), valsartan/amlodipine (n = 272) showed a least-square mean reduction of -16.6 versus -10.8 mmHg by nifedipine GITS (n = 268; mean between-treatment difference: -5.8 mmHg; P < 0.0001) from baseline to week 12. The corresponding results for mean sitting diastolic BP were -8.6 and -4.6 mmHg, respectively (difference: -4.0 mmHg; P < 0.0001). The percentage of patients achieving the BP target (<140/90 or <130/80 mmHg in the absence or presence of diabetes mellitus, respectively) was significantly higher with valsartan/amlodipine (79.0%) versus nifedipine GITS (57.4%; P < 0.0001). The overall incidence rate of adverse events was lower with valsartan/amlodipine (19.2%) than with nifedipine GITS (29.4%; P = 0.004). CONCLUSION: The valsartan/amlodipine 80/5 mg single-pill combination is well tolerated and more effective than nifedipine GITS 30 mg for BP control in Chinese patients with hypertension.

Receptor mediated elevation in FABP4 levels by advanced glycation end products induces cholesterol and triacylglycerol accumulation in THP-1 macrophages.

Excessive formation of advanced glycation end products (AGE) and lipid accumulation in macrophages play a pivotal role in the progression of atherosclerosis in diabetes mellitus. This study aimed to determine the molecular link between AGE-induced fatty acid binding protein 4 (FABP4) expression and macrophage lipid accumulation. AGE-BSA markedly increased macrophage FABP4 expression via engagement of RAGE, a 35-kDa transmembrane receptor that is able to bind extracellular AGE and responsible for the corresponding signal transduction, whereas knockdown of RAGE significantly reversed the FABP4 up-regulation. This effect was further paralleled with elevated intracellular total cholesterol and triacylglycerol levels. Finally, administration of FABP4 inhibitor totally abolished the increased lipid contents in response to AGE-BSA. These results indicate that FABP4 up-regulation is responsible for the enhanced macrophage lipid accumulation by AGE, which may underlie the accelerated formation of foam cells and development of atherosclerotic cardiovascular diseases in diabetic patients.

MiR-146a inhibits oxidized low-density lipoprotein-induced lipid accumulation and inflammatory response via targeting toll-like receptor 4.

Atherosclerosis is an inflammatory process due to oxidized low-density lipoprotein (oxLDL) accumulation in macrophages. We investigated the involvement of microRNAs in oxLDL accumulation and inflammatory response in macrophages. The expression of miR-146a decreases under oxLDL stimulation. MiR-146a significantly reduces intracellular LDL cholesterol content and secretion of interleukin 6, interleukin 8, chemokine (C-C motif) ligand 2 and matrix metallopeptidase 9. Toll-like receptor 4 (TLR4) is a relevant target of miR-146a, and miR-146a inhibits the activation of TLR4-dependent intracellular signaling pathways involved in cytoskeleton rearrangement, lipid uptake, and inflammatory cytokine secretion. These results indicate that miR-146a contributes to the regulation of both oxLDL accumulation and inflammatory response by negatively regulating TLR4 and thereby inhibiting the activation of TLR4-dependent signaling pathways. Over-expression of miR-146a may be useful in the prevention and treatment of atherosclerosis.