Dual Stem Cell Therapy Improves the Myocardial Recovery Post-Infarction through Reciprocal Modulation of Cell Functions

Mesenchymal stromal cells (MSC) are promising candidates for regenerative therapy of the infarcted heart. However, poor cell retention within the transplantation site limits their potential. We hypothesized that MSC benefits could be enhanced through a dual-cell approach using jointly endothelial colony forming cells (ECFC) and MSC. To assess this, we comparatively evaluated the effects of the therapy with MSC and ECFC versus MSC-only in a mouse model of myocardial infarction. Heart function was assessed by echocardiography, and the molecular crosstalk between MSC and ECFC was evaluated in vitro through direct or indirect co-culture systems. We found that dual-cell therapy improved cardiac function in terms of ejection fraction and stroke volume. In vitro experiments showed that ECFC augmented MSC effector properties by increasing Connexin 43 and Integrin alpha-5 and the secretion of healing-associated molecules. Moreover, MSC prompted the organization of ECFC into vascular networks. This indicated a reciprocal modulation in the functionality of MSC and ECFC. In conclusion, the crosstalk between MSC and ECFC augments the therapeutic properties of MSC and enhances the angiogenic properties of ECFC. Our data consolidate the dual-cell therapy as a step forward for the development of effective treatments for patients affected by myocardial infarction.     

Solution polymerization of styrene using biodiesel as a solvent: Effect of biodiesel feedstock

Increasing environmental concerns regarding solvents commonly used in solution polymerization has led to a search for alternatives, such as biodiesel (a.k.a. fatty acid methyl esters or FAME). The effect of the feedstock used in biodiesel production when FAME is used as a polymerization solvent was studied for styrene. A series of homopolymerizations was carried out at different solvent concentrations for two biodiesel feedstocks: soybean oil and 50% yellow grease–50% canola oil. Results were compared to FAME produced from canola oil. Considerable differences in the rate of polymerization were observed, while chain transfer to solvent constants had comparable values. The collected kinetic experimental data were modelled using a polymerization simulator.     

The Implementation of a VHDL-AMS to SPICE Converter

The implementation of a VHDL-AMS to SPICE converter (Vhdl2Spice) to be inserted in a complete CAD environment [1] is described. Vhdl2Spice generates a SPICE netlist by tracing down the VHDL IIR parse tree available from the already existing VHDL analyzer. Corresponding to each VHDL design unit, the output of the converter is represented as a subcircuit in SPICE. By doing so, the hierarchical characteristic of VHDL is retained in the SPICE representation; hence future extension to both programs can be made in parallel. The Vhdl2Spice converter is also a demonstration of the extensibility of the AIRE [2] for a complete integration of VHDL-AMS with other CAD tools.     

The Implementation of a VHDL-AMS to SPICE Converter

The implementation of a VHDL-AMS to SPICE converter (Vhdl2Spice) to be inserted in a complete CAD environment [1] is described. Vhdl2Spice generates a SPICE netlist by tracing down the VHDL IIR parse tree available from the already existing VHDL analyzer. Corresponding to each VHDL design unit, the output of the converter is represented as a subcircuit in SPICE. By doing so, the hierarchical characteristic of VHDL is retained in the SPICE representation; hence future extension to both programs can be made in parallel. The Vhdl2Spice converter is also a demonstration of the extensibility of the AIRE [2] for a complete integration of VHDL-AMS with other CAD tools.     

Cellulose as an extracellular matrix component present in Enterobacter sakazakii biofilms

Cellulose was identified and characterized as an extracellular matrix component present in the biofilm of an Enterobacter sakazakii clinical isolate grown in nutrient-deficient (M9) medium. Using a bacterial artificial cloning approach in Escherichia coli and subsequent screening of transformants for fluorescence on calcofluor plates, nine genes organized in two operons were identified as putatively responsible for the biosynthesis of cellulose. In addition to the genes already described for cellulose production, two more genes were identified, putatively transcribed together with the genes from the first operon. Putative cellulose in E. sakazakii ES5 biofilm grown on glass coverslips was visualized by calcofluor staining and confocal fluorescence laser scanning microscopy. For the first time, the presence of cellulose in biofilms produced by E. sakazakii was confirmed by methylation analysis.     

A New and Robust Method for In‐situ EPR Electrochemistry

A new and simple design of electrochemical setup for in‐situ generation of free radicals to be measured using X‐band (9.5 GHz) electron paramagnetic resonance (EPR) spectrometer is described. The cell parts are all from commercially available components and requires no specially made glassware. The EPR performance of the setup is demonstrated by in‐situ electrochemical generation of organic radical cations and radical anions such as quinones, perylene‐diimide, pyrene, flavin, tryptophan and tyrosine through oxidation or reduction in solution. The well‐resolved EPR spectra of the radical products were simulated and analyzed and the hyperfine coupling constants have been assigned for the interactions of the unpaired electron with the various ring protons and the nitrogen nuclei.     

Choosing to be afraid: Preferences for fear as a function of goal pursuit.

According to an instrumental approach to emotion regulation (M. Tamir, in press), people may not always prefer to feel pleasant emotions and avoid unpleasant ones. Instead, they may be motivated to experience even unpleasant emotions when they might be useful for goal attainment. Given that fear serves to promote successful avoidance, these studies tested this hypothesis by examining preferences for fear in preparation for avoidance goal pursuits. Consistent with the predictions of the instrumental approach, participants preferred to increase their level of fear as they prepared to pursue an avoidance goal. Such preferences were higher than preferences for either excitement or anger and were unique to avoidance (vs. approach or confrontational) goal pursuits. Given the aversive nature of fear, these findings clearly demonstrate that people may sometimes prefer to feel bad if doing so can lead to instrumental benefits. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Chemical modification of flax reinforced polypropylene composites

This paper presents an experimental study on the static and dynamic mechanical properties of nonwoven based flax fibre reinforced polypropylene composites. The effect of zein modification on flax fibres is also reported. Flax nonwovens were treated with zein coupling agent, which is a protein extracted from corn. Composites were prepared using nonwovens treated with zein solution. The tensile, flexural and impact properties of these composites were analysed and the reinforcing properties of the chemically treated composites were compared with that of untreated composites. Composites containing chemically modified flax fibres were found to possess improved mechanical properties. The viscoelastic properties of composites at different frequencies were investigated. The storage modulus of composites was found to increase with fibre content while damping properties registered a decrease. Zein coating was found to increase the storage modulus due to enhanced interfacial adhesion. The fracture mechanism of treated and untreated flax reinforced polypropylene composites was also investigated from scanning electron microscopic studies.     

Analysis of furin ectodomain shedding in epididymal fluid of mammals: demonstration that shedding of furin occurs in vivo

Sperm cell surface proteins and proteins of their surrounding fluids are reported to be proteolytically processed in relation to acquisition of sperm fertility during epididymal transit. Several of these proteins might be potential targets for subtilisin-like pro-protein convertase. Using immunochemistry and mass spectrometry analysis, we found that an 80 kDa form of furin (EC 3.4.21.75) is present in the fluid from the mid-caput to the distal corpus regions of the epididymis of various domestic mammals. This protein is absent from the fluid of the caudal region, suggesting that it is reabsorbed or degraded. The cDNA sequence of ovine furin was obtained and the mRNA was found throughout this organ, although in greater amounts in the mid and distal caput regions. Metabolic labeling with (35)S-amino acids indicated that the protein was synthesized and released from the epithelium only in a restricted area of the mid-caput, suggesting a specific regionalized mechanism of secretion. The fluid protein is not pelleted at 100 000 g and did not react with a C-terminal antibody indicating that it is not bound to membranous materials. These findings demonstrate that a furin ectodomain shedding occurs naturally in vivo in the epididymis where this enzyme could be involved in fluid and/or sperm membrane protein processing.     

Development of a nanoparticulate formulation of diminazene to treat African trypanosomiasis

There is a real need to develop new therapeutic strategies for African trypanosomiasis infections. In our study, we developed a new drug delivery system of diminazene (DMZ), a trypanocidal drug registered for veterinary use. This drug candidate presents a limited efficacy, a poor affinity for brain tissue and instability. The development of colloidal formulations based on a porous cationic nanoparticle with an oily core ((70)DGNP(+)), has potentially two advantages: stabilization of the drug and potential targeting of the parasite. We analyzed two processes of drug loading: in process (DMZ was added during the preparation of (70)DGNP(+) at 80?°C) and post-loading (DMZ was mixed with a (70)DGNP(+) solution at room temperature). Poor stability of the drug was observed using the in process technique. When using the post-loading technique over 80% drug entrapment efficiency was obtained at a ratio of DMZ:phospholipids (wt:wt) < 5%. Moreover, DMZ loaded into (70)DGNP(+) was found to be protected against oxidation and was stable for at least six months at 4?°C. Finally, in vitro tests on T.b. brucei showed an increased efficacy of DMZ loaded in (70)DGNP(+).