Synthesis, Kinetic Evaluation and Utilization of a Biotinylated Dipeptide Proline Diphenyl Phosphonate for the Disclosure of Dipeptidyl Peptidase IV-like Serine Proteases

In this study, we report on the synthesis, kinetic characterisation, and application of a novel biotinylated and active site-directed inactivator of dipeptidyl peptidase IV (DPP-IV). Thus, the dipeptide-derived proline diphenyl phosphonate NH(2)-Glu(biotinyl-PEG)-Pro(P)(OPh)(2) has been prepared by a combination of classical solution- and solid-phase methodologies and has been shown to be an irreversible inhibitor of porcine DPP-IV, exhibiting an over all second-order rate constant (k(i)/K(i)) for inhibition of 1.57 x 10(3) M(-1) min(-1). This value compares favourably with previously reported rates of inactivation of DPP-IV by dipeptides containing a P(1) proline diphenyl phosphonate grouping [B. Boduszek, J. Oleksyszyn, C.M. Kam, J. Selzler, R.E. Smith, J.C. Powers, Dipeptide phophonates as inhibitors of dipeptidyl peptidase IV, J. Med. Chem. 37 (1994) 3969-3976; B.F. Gilmore, J.F. Lynas, C.J. Scott, C. McGoohan, L. Martin, B. Walker, Dipeptide proline diphenyl phosphonates are potent, irreversible inhibitors of seprase (FAPalpha), Biochem, Biophys. Res. Commun. 346 (2006) 436-446.], thus demonstrating that the incorporation of the side-chain modified (N-biotinyl-3-(2-(2-(3-aminopropyloxy)-ethoxy)-ethoxy)-propyl) glutamic acid residue at the P(2) position is compatible with inhibitor efficacy. The utilisation of this probe for the detection of both purified dipeptidyl peptidase IV and the disclosure of a dipeptidyl peptidase IV-like activity from a clinical isolate of Porphyromonas gingivalis, using established electrophoretic and Western blotting techniques previously developed by our group, is also demonstrated.

Electron impact excitation of C IV

Energy levels and radiative rates for transitions among the lowest 24 fine-structure levels belonging to the ls(2) nl (n <5) configurations of Li-like C IV have been calculated using the fully relativistic GRASP code. Additionally, collision strengths for transitions among these levels have been computed over a wide energy range below 28 Ry, using the Dirac Atomic R- matrix Code. Resonances have been resolved in a fine energy mesh in order to calculate the effective collision strengths. Results for radiative rates, collision strengths, and effective collision strengths are presented for all transitions. Comparisons with other available results are made, and the accuracy of the present data is assessed. Energy levels are expected to be accurate to within 1%, while other parameters are probably accurate to better than 20%.

Welfare Regimes and “progressive” governments in Latin America: The cases of Venezuela, Ecuador and Bolivia

Several authors have applied the concept of Welfare Regimens for studying social policy in Latin America (Esping-Andersen, 1993 and 2000). Among others, Martínez Franzoni (2007) develops a typology, with fi eld work is at the turn of the millennium, and establishes three categories: State-productivist regime, state-protectionist and family orientated. Most countries in the region are placed in the latter category. The hypothesis of this article argues that with the emergence of governments considered “left” or “progressive” in several countries of the region from the late ‘90s and, more decisively, in 2000’, the map of welfare regimes models could have mutated substantively. The nationally transformative experiences are different (various socio-economic realities and political action in which they are located exists) but they have several contact points that can be summarized in a greater state intervention in different areas previously closed to their operating and recovery of important functions of welfare and care of the population by the government. The paper discusses with an exploratory and descriptive approach the welfare schemes that would shape in three countries that have constitutionalized the change from the neoliberal paradigm: Venezuela, Bolivia and Ecuador.

The sector of olive-oil cooperatives and the use of ICT: A comparative study regarding othe legal forms

The current global environment and the general increase in the spread and use of Information Technology and Communication (ICT) by companies and consumers, make the use of these technologies as essential to confront the growing competition in the market. Focused on this sector, in this research we analyze the use of electronic commerce, as through websites as through electronic markets, and the use of social networking tools as enablers of business. For this aim, we conducted a comparative analysis between the Andalusian olive oil cooperatives and other legal forms which are present in the sector.

Multi-zone TAP-reactors theory and application - IV. Ideal and non-ideal boundary conditions

We study the influence of non-ideal boundary and initial conditions (BIC) of a temporal analysis of products (TAP) reactor model on the data (observed exit flux) analysis. The general theory of multi-response state-defining experiments for a multi-zone TAP reactor is extended and applied to model several alternative boundary and initial conditions proposed in the literature. The method used is based on the Laplace transform and the transfer matrix formalism for multi-response experiments. Two non-idealities are studied: (1) the inlet pulse not being narrow enough (gas pulse not entering the reactor in Dirac delta function shape) and (2) the outlet non-ideality due to imperfect vacuum. The effect of these non-idealities is analyzed to the first and second order of approximation. The corresponding corrections were obtained and discussed in detail. It was found that they are negligible. Therefore, the model with ideal boundary conditions is proven to be completely adequate to the description and interpretation of transport-reaction data obtained with TAP-2 reactors.

Uso problemático de las redes sociales en estudiantes universitarios

Los avances que están produciéndose en el ámbito académico con el surgimiento de herramientas de la Web 2.0 y el empleo masivo por parte de los estudiantes de la redes sociales para comunicarse entre ellos, está haciendo que el panorama educativo se encuentre ante unos desafíos a los que tiene que dar respuesta. La investigación que aquí se presenta tuvo como objetivo principal analizar el estado del empleo de la redes sociales por parte alumnado universitario, así como los posibles malos hábitos y usos problemáticos de las mismas. Se utilizó como instrumento de recogida de información un cuestionario “ad hoc” con un total de 23 ítems. Se concluye que el alumnado en general no posee malos hábitos en el empleo de las redes sociales, igualmente los resultados obtenidos ponen de manifiesto que su utilización no está plenamente integrada en las instituciones universitarias de educación superior, así como que los estudiantes no las emplean/usan como herramienta fundamental para las resolución de cuestiones académicas.