AimsGiven the importance of inflammation in the onset and progression of diabetic cardiomyopathy, we investigated the potential protective effects of triptolide, an anti-inflammatory agent, in streptozotocin-induced diabetic rat model and in H9c2 rat cardiac cells exposed to high glucose.Methods and resultsDiabetic rats were treated with triptolide (100, 200, or 400 μg/kg/day respectively) for 6 weeks. At the end of this study, after cardiac function measurements were performed, rats were sacrificed and their hearts were harvested for further histologic and molecular biologic analysis. Enhanced activity and expression of nuclear factor-kappaB (NF-κB) p65 in diabetic hearts were associated with increased inflammatory response, as demonstrated by increased pro-inflammatory cytokines, cell adhesion molecules and invading inflammatory cells, as well as increased fibrosis, in line with impaired left ventricular function. Triptolide attenuated these morpho-functional alterations. Furthermore, triptolide (20 ng/ml) also attenuated high glucose-induced inflammation in H9c2 rat cardiac cells.ConclusionOur data demonstrate that anti-inflammatory effects of triptolide involving the NF-κB signaling pathway can improve left ventricular function under diabetic conditions, suggesting triptolide treatment might be beneficial in diabetic cardiomyopathy.

Global AS is a sensitive and reproducible parameter to detect early and subtle LV systolic dysfunction, showing greater feasibility than other conventional strain parameters.

A series of substituted poly(p-phenyleneethynylene)s, PPE, were synthesized by alkyne metathesis. The substituents dibutyl 4a, dioctyl 4b, ditetradecyl 4c, di-2-ethylhexyl 4d, and di-2cyclohexylethyl 4e were placed on the 2,5-positions of the phenyl rings. X-ray diffraction studies indicated that the main chains of each polymer were arranged in regular, layered arrays. Liquid crystalline structures were obtained by polarized optical microscopy in PPE 4b, 4c, and 4d. The temperatures of isotropization of the liquid crystalline structures coincided with the disordering temperatures determined by differential scanning calorimetry. The UV absorption spectra showed a gradual blue shift of the λ max from 4a to 4e, suggesting a decrease in the electronic delocalization along the chain as the size and geometry of the side group changed. The photoluminescence spectra in dilute toluene solutions are consistent with vibronic coupling and emission from localized excited states. The emission spectra of thin films show characteristics typical excimer or aggregate formation in the solid state. Last, an improved method of molecular weight determination by end group analysis was devised.

Novel sulfonated poly(arylene ether)s, characterized as being highly sterically encumbered, were synthesized for investigation as the ionomer in proton exchange membrane fuel cell (PEMFC) catalyst layers. Catalyst-coated membranes were prepared via their incorporation into alcohol-based catalyst inks, devoid of the high-boiling, polar aprotic solvents typically required for hydrocarbonbased ionomer inks. Catalyst layers thicknesses increased from 8.5 to 9.1 μm when the hydrocarbon ionomer loading was increased from 20 to 40 wt%, but resulted in a 77% loss in pore volume for fully hydrated electrodes. The catalyst layers possessed similar electrochemical surface areas and net ionic conductivity, yet catalyst layers containing 20 wt% ionomer yielded the highest overall fuel cell performance and considerably outperformed catalyst layers prepared from inks that contained high-boiling solvents. Perfluorosulfonic acid (PFSA) ionomers offer exceptional physical and chemical stability for proton exchange membrane fuel cells (PEMFCs) as well as high proton conductivity, 1 but are relatively expensive, possess high gas permeability, and are of limited use at high temperature and low humidity.2 Hence, attention has focused on the investigation of hydrocarbon (HC)-based solid polymer electrolytes for use as PEMs.3 Compared to PFSA ionomers, there is a large breadth of potentially low cost monomers available for synthesis of HC-based analogues. However, while significant progress has been made studying HC solid polymer electrolytes as membranes, 4 there is very little understanding of their incorporation as ionomer in catalyst layers.5 Studies on PFSA ionomer-based catalyst layers have revealed the complex nature of the interactions between ionomer, Pt, and the carbon support.6-8 The agglomeration of PFSA ionomer in catalyst inks and during the catalyst layer deposition process are believed to dramatically affect proton, gas and water transport through the catalyst layer. A similar impact is expected for catalyst layers containing HC-based ionomers. A previous report by J. Peron et al., for example, demonstrated the influence of sulfonated poly(ether ether ketone) (sPEEK) loading in the catalyst layer (CL). 9 In each case, sPEEKbased CLs were found to contain smaller aggregated catalyst particles and smaller pore sizes than their PFSA-based counterparts. Inferior in-situ performance was found for all sPEEK-containing electrodes, 10