Poly(Dibenzothiophene-Terphenyl Piperidinium) for High-performance Anion Exchange Membrane Water Electrolysis.

The anion exchange membrane water electrolysis is widely regarded as the next-generation technology for producing green hydrogen. The OH- conductivity of the anion exchange membrane plays a key role in the practical implementation of this device. Here, we present a series of Z-S-x membranes with dibenzothiophene groups. These membranes contain sulfur-enhanced hydrogen bond networks that link surrounding surface site hopping regions, forming continuous OH- conducting highways. Z-S-20 has a high through-plane OH- conductivity of 182 ± 28 mS cm-1 and ultralong stability of 2650 h in KOH solution at 80 °C. Based on rational design, we achieved a high PGM-free alkaline water electrolysis performance of 7.12 A cm-2 at 2.0 V in a flow cell and demonstrated durability of 650 h at 2 A cm-2 at 40 °C with a cell voltage increase of 0.65 mV/h.

Elevated D-dimer levels predict adverse outcomes in hospitalised elderly patients with chronic heart failure.

BACKGROUND: Elevated D-dimer levels have been associated with poor outcomes in patients with cardiovascular disease. AIM: To study this association in elderly patients with chronic heart failure (CHF). METHODS: We analysed 1355 elderly patients who were admitted with CHF. All patients had D-dimer levels measured within the first 24 h following admission. A multivariate logistic regression model was used to assess the variables associated with chronic kidney disease. We used Cox regression analysis to assess the multivariable relationship between the D-dimer and subsequent all-cause death. RESULTS: In the multiple logistic regression analysis, the D-dimer was identified as a risk factor for chronic kidney disease (odds ratio = 1.278, 95% confidence interval 1.138 to 1.436, P < 0.001). The optimal cut-off level for D-dimer to predict all-cause death was found to be >885 ng/mL. In the multivariate Cox proportional-hazards model, a D-dimer level >885 ng/mL remained significantly associated with all-cause death (hazard ratio = 2.003, 95% confidence interval 1.334 to 3.010, P = 0.001). Additional analyses revealed that higher D-dimer levels were associated with an increased risk of all-cause death irrespective of the subtype of heart failure (including heart failure with reduced ejection fraction and heart failure with preserved ejection fraction). CONCLUSION: In elderly patients with CHF, measurement of D-dimer levels may help to risk stratify these patients, and high D-dimer levels might be regarded as a warning sign to intensify therapy.

Hemoglobin A1c and risk of left atrial thrombus and spontaneous echo contrast in non-valvular atrial fibrillation patients.

OBJECTIVES: To evaluate the relationship between hemoglobin A1c (HbA1c) and risk of left atrial thrombus/spontaneous echo contrast (LAT/SEC) in non-valvular atrial fibrillation (AF) patients. METHODS: In this retrospective study, 1158 consecutive non-valvular AF patients undergoing transesophageal echocardiography prior to radiofrequency catheter ablation or electric cardioversion were enrolled. Baseline characteristics were collected and analyzed. RESULTS: There were 87 (7.5%) patients with LAT/SEC. The HbA1c levels in the patients with LAT/SEC were significantly higher than that in patients without LAT/SEC (6.13 ± 0.41 vs. 5.89 ± 0.45 µmol/L, P < 0.001). The optimal cut-off point for HbA1c predicting LAT/SEC was 6.1% determined by receiver-operating characteristic curve. The area under the curve is 0.788 (95% confidence interval: 0.764-0.812). HbA1c ≥6.1% was an independent risk factor for LAT/SEC (odds ratio, 1.74; 95% confidence interval, 1.01-2.98; P = 0.045). CONCLUSIONS: Elevated HbA1c indicated a significantly increased risk for LAT/SEC in non-valvular AF patients. HbA1c might have significance in predicting the risk for prothrombotic state in non-valvular AF patients.

Sulforaphane prevents rat cardiomyocytes from hypoxia/reoxygenation injury in vitro via activating SIRT1 and subsequently inhibiting ER stress.

AIM: Sulforaphane (SFN), a natural dietary isothiocyanate, is found to exert beneficial effects for cardiovascular diseases. This study aimed to investigate the mechanisms underlying the protective effects of SFN in a model of myocardial hypoxia/reoxygenation (H/R) injury in vitro. METHODS: Cultured neonatal rat cardiomyocytes pretreated with SFN were subjected to 3-h hypoxia followed by 3-h reoxygenation. Cell viability and apoptosis were detected. Caspase-3 activity and mitochondrial membrane potential (ΔΨm) was measured. The expression of ER stress-related apoptotic proteins were analyzed with Western blot analyses. Silent information regulator 1 (SIRT1) activity was determined with SIRT1 deacetylase fluorometric assay kit. RESULTS: SFN (0.1-5 µmol/L) dose-dependently improved the viability of cardiomyocytes, diminished apoptotic cells and suppressed caspase-3 activity. Meanwhile, SFN significantly alleviated the damage of ΔΨm and decreased the expression of ER stress-related apoptosis proteins (GRP78, CHOP and caspase-12), elevating the expression of SIRT1 and Bcl-2/Bax ratio in the cardiomyocytes. Co-treatment of the cardiomyocytes with the SIRT1-specific inhibitor Ex-527 (1 µmol/L) blocked the SFN-induced cardioprotective effects. CONCLUSION: SFN prevents cardiomyocytes from H/R injury in vitro most likely via activating SIRT1 pathway and subsequently inhibiting the ER stress-dependent apoptosis.

Erythropoietin pretreatment suppresses inflammation by activating the PI3K/Akt signaling pathway in myocardial ischemia-reperfusion injury.

Erythropoietin (EPO), a glycoprotein originally known for its important role in the stimulation of erythropoiesis, has recently been shown to have significant protective effects in animal models of kidney and intestinal ischemia-reperfusion injury (IRI). However, the mechanism underlying these protective effects remains unclear. The aim of the current study was to evaluate the effects of EPO on myocardial IRI and to investigate the mechanism underlying these effects. A total of 18 male Sprague Dawley rats were randomly divided into three groups, namely the sham, IRI-saline and IRI-EPO groups. Rats in the IRI-EPO group were administered 5,000 U/kg EPO intraperitoneally 24 h prior to the induction of IRI. IRI was induced by ligating the left descending coronary artery for 30 min, followed by reperfusion for 3 h. Pathological changes in the myocardial tissue were observed and scored. The levels of the proinflammatory cytokines, interleukin (IL)-6, IL-1ß and tumor necrosis factor (TNF)-α, were evaluated in the serum and myocardial tissue. Furthermore, the effects of EPO on phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signaling and EPO receptor (EPOR) phosphorylation were measured. Pathological changes in the myocardial tissue, increased expression levels of TNF-α, IL-6 and IL-1ß in the myocardium, and increased serum levels of these mediators, as a result of IRI, were significantly decreased by EPO pretreatment. The effects of EPO were found to be associated with the activation of PI3K/Akt signaling, which suppressed the inflammatory responses, following the initiation of EPOR activation by EPO. Therefore, EPO pretreatment was demonstrated to decrease myocardial IRI, which was associated with activation of EPOR, subsequently increasing PI3K/Akt signaling to inhibit the production and release of inflammatory mediators. Thus, the results of the present study indicated that EPO may be useful for preventing myocardial IRI.

Reactions of 3-benzoyl-7-dimethylamino-4-hydroxycoumarin and their potential applications in solution- and solid-phase synthesis.

3-Benzoyl-7-dimethylamino-4-hydroxycoumarin was synthesized and its UV-vis spectra in various mixtures of MeOH and CH(2)Cl(2) were measured. The diketone lactone exists mainly in the exocyclic-enol form in protic solvents and the endocyclic-enol form in nonpolar solvents. Acetylation, amination and methylation products of the diketone lactone were characterized by X-ray crystallography. The results indicated that acetylation of coumarin-based diketone lactones occurs exclusively at the 4-hydroxy group, but that amination takes place specifically at the C-3 carbonyl group. Among the prepared compounds, amination products were found to exhibit photochromic property and colorimetric ion-sensing ability, and methylation product has the potential to function as a primary amine protection group.

A new anti-HIV lupane acid from Gleditsia sinensis Lam.

A new lupane acid, 2beta-carboxyl,3beta-hydroxyl-norlupA (1)-20 (29)-en-28-oic acid (1), together with five known lupane acid derivatives (2-6), were isolated from the stings of Gleditsia sinensis Lam.. Their structures were elucidated on the basis of 1D and 2D NMR techniques. All these known compounds were isolated from this genus for the first time. The new compound 1 showed strong anti-HIV activity.

Study on improving the selectivity of compounds that inhibit two PI3Ks (gamma and delta).

A desirable characteristic of PI3K inhibitors is their selectivity. Up to now, there has been no report that describes the 3 D-structure differences between two PI3Ks (delta and gamma) and applies them to designing selective compounds. In the present study, we used an approach combining protein-structure modeling, GRID/PCA (Principal Component Analysis) and docking methods to investigate the detail interactions of the two PI3Ks with various chemical groups. At first, we constructed a 3 D-model of the PI3Kdelta catalytic subunit with the program Modeller7.0 based on the high resolution X-ray structure of the PI3Kgamma catalytic subunit, and then employed GRID and PCA to reveal the most relevant structural and physicochemical differences between the two PI3Ks related to their selectivity. As a result, the analysis unveiled the most important regions on the two PI3Ks that should be taken into account for the design of selective inhibitors. Finally, based on activity data of 10 PI3Kdelta-selective compounds, a docking study validated the results of the GRID/PCA method, which suggested that the approach could provide clear guidelines for selective drug design.