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By definition, economic policy is “the sum of measures taken by state authorities in order to guarantee economic growth, employment, balancing the balance of foreign payments, prices stability, decreasing the discrepancies and also guaranteeing national independence” (Macroeconomic dictionary – A. Bacescu, M. Bacescu). Summarizing, we may state that economic policy is represented by the behavior of state authorities within the functioning of the economy of the country. Anti crisis economic policies structure the mechanisms and instruments that state authorities use in order to diminish the shocks generated by the economic decrease.

Objectives Here we assess the intrinsic functions of the chemokine receptor CXCR4 in remodeling after myocardial infarction (MI) using Cxcr4 heterozygous (Cxcr(4+/-)) mice. Background Myocardial necrosis triggers complex remodeling and inflammatory changes. The chemokine CXCL12 has been implicated in protection and therapeutic regeneration after MI through recruiting angiogenic outgrowth cells, improving neovascularization and cardiac function, but the endogenous role of its receptor CXCR4 is unknown. Methods MI was induced by ligation of the left descending artery. Langendoff perfusion, echocardiography, quantitative immunohistochemistry, flow cytometry, angiogenesis assays, and cardiomyocyte analysis were performed. Results After 4 weeks, infarct size was reduced in Cxcr4(+/-) mice compared with wild-type mice and in respective bone marrow chimeras compared with controls. This was associated with altered inflammatory cell recruitment, decreased neutrophil content, delayed monocyte infiltration, and a predominance of Gr1(low) over classic Gr1(high) monocytes. Basal coronary flow and its recovery after MI were impaired in Cxcr4(+/-)mice, paralleled by reduced angiogenesis, myocardial vessel density, and endothelial cell count. Notably, no differences in cardiac function were seen in Cxcr4(+/-)mice compared with wild-type mice. Despite defective angiogenesis, Cxcr4(+/-) mouse hearts showed no difference in CXCL12, vascular endothelial growth factor or apoptosis-related gene expression. Electron microscopy revealed lipofuscin-like lipid accumulation in Cxcr4(+/-) mouse hearts and analysis of lipid extracts detected high levels of phosphatidylserine, which protect cardiomyocytes from hypoxic stress in vitro. Conclusions CXCR4 plays a crucial role in endogenous remodeling processes after MI, contributing to inflammatory/progenitor cell recruitment and neovascularization, whereas its deficiency limits infarct size and causes adaptation to hypoxic stress. This should be carefully scrutinized when devising therapeutic strategies involving the CXCL12/CXCR4 axis. (J Am Coll Cardiol 2011;58:2415-23)

Segmented poly(ester-siloxane)urethanes containing hard and soft segments were prepared by melt polyaddition using a multistep procedure. The soft segments based on poly(ethylene glycol adipate)diol as ester sequences and α,ω-poly(dimethylsiloxane)diol as silicone sequences were synthesized. The hard segments were based on aromatic or aliphatic diisocyanates and butanediol was used as chain extender. These polyurethane materials were analysed by differential scanning calorimetry and dynamic-mechanical analysis measurements. The shapes of thermal plots are significantly influenced by the soft and hard segment structures and also the compositional parameters.

Mechanically stable microcapsules, with sizes of 0.4-1.5 mm, have been produced with permeabilities appropriate for applications involving living cells and controlled delivery. Polyvinylamine hydrochloride was employed alone, in miXtures with poly(methylene-co-guanidine) hydrochloride, or as a coating material for pre-formed capsules. The influence of polymer molar mass, the ratio between the two polycations, the coating time, and the capsule size on the properties of the capsules were analysed. The competitive displacement of one polycation with another in the polysaccharide matrix was also documented. The properties of the capsules vary remarkably, depending of the polyelectrolyte combinations used for their preparation. Specifically, capsules could withstand compressive loads of between 0.09-1.67 N, while the permeability varied from 10-120 kDa. Both are within the ranges required for clinical immunosuppressive therapies.

New polydimethylsiloxane-containing segmented block copolyure-thanes were obtained from aromatic or aliphatic diisocyanates, 1,4-butanediol and poly(ethylene glycol)adipate using a multistep polyaddition process. Specific refractive index increments of these segmented copolymers in N,N-dimethyl-formamide have been determined by the Lorenz-Lorentz equation and the corresponding group contributions to the molar refraction and to the molar volume. The results are in good agreement with the experimental values. Also, from the dependence between the specific refractive index increments and the weight fraction of 4,4′-methylene diphenylene diisocyanate units, w d , the ν0 and dν/dw d coefficients have been evaluated and the results are situated between the values reported in literature.

The paper discusses the behaviour of polydimethylsiloxanes with different terminal groups as induced by polymer molecular weight and solvent mixture composition in dilute solution.

This paper discusses the influence of solvent nature and temperature on the intrinsic viscosity, the mean dimensions of the polymer chain and the [η]–M relationship for different molecular weight polydimethylsiloxanes with amino end groups in toluene/nitromethane (solvent/nonsolvent) mixtures.

The present paper continues our previous studies on solution behaviour of polydimethylsiloxanes with amino end groups. The total and preferential adsorption coefficients for aminopropyl - terminated polydimethylsiloxanes in toluene (solvent)/ nitromethane (nonsolvent) dilute solutions are determined.

The ternary system 1-chlorobutane (theta solvent)/2-butanol (nonsolvent)/poly(methyl methacrylate) was investigated by use of the theoretical Flory-Huggins-Pouchly model. The determination of the interaction parameters through the second virial coefficient according to the equation proposed by Pouchly was analyzed.

The paper discusses the validity criteria of the theories on the excluded volume effect for high molecular weight Ψ(Z) polyacrylonitrile. The experimental data obtained for both the interpenetration function ψ(Z) and the hydrodynamic function II(Z) satisfactorily approach the theoretical predictions of the renormalized two-parameter theory for high excluded volume.

The paper investigates the agreement between experimental and theoretical data for the second virial coefficient A2 and for the intrinsic viscosity [η] for the acetonitrile/chlorobutane/poly(methyl methacrylate) ternary system.

Objective:To characterize the premorbid cognitive and behavioral abilities in apparently healthy adolescents who at a later time will be diagnosed with schizophreniform disorder or schizophrenia.Background:Clarifying the pathological relationship between subtle intellectual and behavioral abnormalities and disease could provide markers for the early prediction of future psychosis.Method:Premorbid data on young male patients admitted to the Department of Psychiatry of the Central Military Hospital in Bucharest, Romania, between 1996 and 2002 and diagnosed with a first episode of psychosis or schizophreniform disorder were collected. The premorbid data consisted in the test scores of intellectual functioning and personality traits were collected by the Romanian Draft Board in order to assesses their aptitude to serve in the military. Premorbid cognitive and behavioral scores of male patients (cases=157) were compared with the scores of healthy male individuals (non-cases=169) matched for age, education, and geographic area of residence. The tests were administered when subjects were 18 years of age (initial screening) and the entire assessment was completed and concluded when subjects reached 20 years of age (actual conscription).Results:As a group, apparently healthy males later admitted for a first episode of psychosis or schizophreniform disorder, obtained lower (worse) scores on the Raven Progressive Matrices test and on relevant personality traits in comparison to controls.Conclusions:The results add to the accumulating body of evidence suggesting that aspects of schizophrenia manifest years before the illness is formally diagnosed. Despite these results, more studies are needed to improve the diagnosing specificity and predictive value of the premorbid cognitive and behavioral manifestations, before they can be used as markers in models of primary or secondary prevention.

The rheological behaviour of dissolved polymers is very complex. Both experiment and theory in this field have undergone rapid development in recent years. Therefore, we describe the possibilities of predicting the viscoelastic properties as well as the shear stability using the entanglement and reptation concepts and exemplifying mainly with narrow distributed polystyrene samples. The viscoelastic properties are discussed in relation to molar mass, concentration, solvent quality, chemical structure and shear rate. The structure-property relationships derived here permit the prediction of both the zero-shear viscosity, η0, as well as the shear rate dependent viscosity η(\( \dot \gamma \)). These relationships can be extended to non-Newtonian fluids. For solutions of coiled polymers in a thermodynamically good solvent, five distinct states of solution are formed: ideally dilute solution, semi-dilute particle solution, semi-dilute network solution, concentrated particle solution and concentrated network solution. For non-homogeneous, semi-dilute (moderately concentrated) solutions the slope in the linear region of the flow curve [η=f(\( \dot \gamma \))] must be standardised against the overlap parameter c· [η ]. Furthermore, it is possible to predict the onset of shear degradation of polymeric liquids subjected to a laminar velocity field on the basis of molecular modeling. Also described is the phenomenon that the elastic nature (first normal stress difference) may overwhelm the viscous nature (shear stress) at relatively low shear rates. This high elasticity can cause deviation from laminar flow conditions and the onset conditions can be detected by plotting Sr=f(τ12).

Polyelectrolyte complex membrane formation has been studied, on-line, using the synthetic boundary technique of an Optima XL-I analytical ultracentrifuge. This recent method, established by the first author, has now been evaluated concerning its sensitivity to monitor differences in the membrane formation if the membrane components and experimental conditions are varied. For this purpose the membrane formation of sodium alginate with three polycations, poly(vinyl-amine) hydrochloride, poly(L-ly-sine) hydrochloride, and chitosan oligomers, was examined under various experimental conditions. In addition, two approaches have been developed and applied to evaluate the membrane formation process and the membrane quality on the basis of the experimentally received radial absorption scans. The first approach generalizes the membrane growth and its direction, resulting in a time-dependent description of the membrane geometry. The second one considers the membrane thickness as a function of time and might, therefore, serve to calculate the growth velocity or shrinking of the membrane, but not the directions of growth or shrinking. The investigations revealed a sufficient sensitivity of the method leading to the conclusion that the membranes formed in this study differ in thickness, symmetry, homogeneity, and the kinetics of formation. Consequently, the demonstrated sensitivity of this ultracentrifugation technique offers novel extended possibilities for basic studies of the polyelectrolyte complex membrane formation. Moreover, the goal-directed optimization of such membranes for practical applications can be supported.