266 research outputs found

    Pay as you Go System versus Fully Funded Pension in Peru

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    The following paper analyses the sustainability of the Peruvian ?Pay as You Go System? which is provided by the Government. In Peru, the ?Pay as you Go System? coexists with Private Pension Funds or ?Fully Funded Pension?. Sometimes both systems compete with each other with advantages and disadvantages between them. We found that ?Pay as You Go System? cannot be sustainable over a long period of time. In addition, based on a comparative analysis of advantages and disadvantages, we propose some recommendations to make Private Pension Funds (Fully Funded Pension) the best alternative to Pay as You Go System.Este trabajo analiza la sostenibilidad del sistema pensional colectivo implementado por el gobierno peruano. En Per?, este sistema coexiste con el de fondos privados de pensiones o fondo individual. En algunos casos, estos dos sistemas compiten entre s?, con sus ventajas y desventajas entre ambos sistemas. Seg?n nuestros hallazgos, el sistema pensional de reparto colectivo de pensiones no es sostenible en un largo plazo. Asimismo, sobre la base de un an?lisis comparativo de las ventajas y desventajas entre ambos sistemas, se formulan algunas recomendaciones para que los fondos privados de pensi?n (Sistema Individual) se conviertan en la mejor alternativa al sistema pensional colectivo

    Relative power and efficiency as a main determinant of banks? profitability in Latin America

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    Despite the financial sector liberalization and openness that started in the earlier 90's and significant macroeconomic development as well as increasing inflow of capital toward the region, there is not any evidence of the reduction of interest rates as well as banks' profits in Latin America. In this paper we develop a model to estimate the determinants of Latin American banks' profitability and, try to understand the reasons why banks are reluctant to decrease their interest rate spreads even when change in competitiveness in the financial system is improving. By using Data Envelopment Analysis to better exploit the information of several variables at the same time and, by employing a sample of 200 Banks located in Argentina, Bolivia, Brazil, Costa Rica, Ecuador, El Salvador, Mexico, Nicaragua, Paraguay, Peru, Uruguay and Venezuela; we find that banks' profits grew consistently above the normal levels of profits adjusted by risk. Our results show that banks in Latin America have been profiting from their oligopolistic position in detriment of their clients in particular and of their whole economy in general

    Factores cr?ticos de ?xito y su influencia en la intenci?n de recompra en clientes en un centro comercial: caso Plaza Norte

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    Los centros comerciales representan, hoy en d?a, uno de los destinos predilectos de los clientes del sector retail, porque ante los avances de la propuesta original creada por el arquitecto Gruen, estos establecimientos se han repotenciado e ido adaptando a sus necesidades y exigencias. En la actualidad, los clientes recurren a estos lugares para satisfacer m?s que la mera necesidad de adquirir productos y servicios, lo ve como el punto de encuentro ideal para ?l, para la familia y amigos. El entretenimiento es otra necesidad que el cliente busca satisfacer, pero tambi?n buscar? su conveniencia, una ubicaci?n estrat?gica, pero tambi?n su f?cil acceso. En definitiva, ir? tras una experiencia de visita o compra satisfactoria. Para esto, los administradores de centros comerciales deber?n analizar los factores cr?ticos de ?xito que le permiten responder a las demandas de su p?blico objetivo, pero sobre todo generar un compromiso con el cliente para dar pie a la formaci?n de la lealtad. De esta forma, la organizaci?n vivir? en la mente del consumidor ante su b?squeda de productos o servicios del recinto, para luego, de haber surgido la satisfacci?n, generar un v?nculo que posteriormente lo lleve a una intenci?n de recompra

    Epigenetic Silencing of Tumor Suppressor miR-124 Directly Supports STAT3 Activation in Cutaneous T-Cell Lymphoma

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    Increasing evidence supports a potential role for STAT3 as a tumor driver in cutaneous T-cell lymphomas (CTCL). The mechanisms leading to STAT3 activation are not fully understood; however, we recently found that miR-124, a known STAT3 regulator, is robustly silenced in MF tumor-stage and CTCL cells. OBJECTIVE: We studied here whether deregulation of miR-124 contributes to STAT3 pathway activation in CTCL. METHODS: We measured the effect of ectopic mir-124 expression in active phosphorylated STAT3 (p-STAT3) levels and evaluated the transcriptional impact of miR-124-dependent STAT3 pathway regulation by expression microarray analysis. RESULTS: We found that ectopic expression of miR-124 results in massive downregulation of activated STAT3 in different CTCL lines, which resulted in a significant alteration of genetic signatures related with gene transcription and proliferation such as MYC and E2F. CONCLUSIONS: Our study highlights the importance of the miR-124/STAT3 axis in CTCL and demonstrates that the STAT3 pathway is regulated through epigenetic mechanisms in these cells. Since deregulated STAT3 signaling has a major impact on CTCL initiation and progression, a better understanding of the molecular basis of the miR-124/STAT3 axis may provide useful information for future personalized therapies

    Novel CYP4F22 mutations associated with autosomal recessive congenital ichthyosis (ARCI). Study of the CYP4F22 c.1303C>T founder mutation

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    Mutations in CYP4F22 cause autosomal recessive congenital ichthyosis (ARCI). However, less than 10% of all ARCI patients carry a mutation in CYP4F22. In order to identify the molecular basis of ARCI among our patients (a cohort of ninety-two Spanish individuals) we performed a mutational analysis using direct Sanger sequencing in combination with a multigene targeted NGS panel. From these, eight ARCI families (three of them with Moroccan origin) were found to carry five different CYP4F22 mutations, of which two were novel. Computational analysis showed that the mutations found were present in highly conserved residues of the protein and may affect its structure and function. Seven of the eight families were carriers of a highly recurrent CYP4F22 variant, c.1303C>T; p.(His435Tyr). A 12Mb haplotype was reconstructed in all c.1303C>T carriers by genotyping ten microsatellite markers flanking the CYP4F22 gene. A prevalent 2.52Mb haplotype was observed among Spanish carrier patients suggesting a recent common ancestor. A smaller core haplotype of 1.2Mb was shared by Spanish and Moroccan families. Different approaches were applied to estimate the time to the most recent common ancestor (TMRCA) of carrier patients with Spanish origin. The age of the mutation was calculated by using DMLE and BDMC2. The algorithms estimated that the c.1303C>T variant arose approximately 2925 to 4925 years ago, while Spanish carrier families derived from a common ancestor who lived in the XIII century. The present study reports five CYP4F22 mutations, two of them novel, increasing the number of CYP4F22 mutations currently listed. Additionally, our results suggest that the recurrent c.1303C>T change has a founder effect in Spanish population and c.1303C>T carrier families originated from a single ancestor with probable African ancestry

    Caffeine, a Risk Factor for Osteoarthritis and Longitudinal Bone Growth Inhibition

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    Osteoarthritis (OA), the most common chronic rheumatic disease, is mainly characterized by a progressive degradation of the hyaline articular cartilage, which is essential for correct joint function, lubrication, and resistance. Articular cartilage disturbances lead to joint failure, pain, and disability. Hyaline cartilage is also present in the growth plate and plays a key role in longitudinal bone growth. Alterations of this cartilage by diverse pathologies have been related to longitudinal bone growth inhibition (LBGI), which leads to growth retardation. Diet can play a crucial role in processes involved in the OA and LBGI's onset and evolution. Specifically, there is ample evidence pointing to the negative impacts of caffeine consumption on hyaline cartilage. However, its effects on these tissues have not been reviewed. Accordingly, in this review, we summarize all current knowledge in the PubMed database about caffeine catabolic effects on articular and growth plate cartilage. Specifically, we focus on the correlation between OA and LBGI with caffeine prenatal or direct exposure. Overall, there is ample evidence indicating that caffeine intake negatively affects the physiology of both articular and growth plate cartilage, increasing consumers predisposition to suffer OA and LBGI. As a result, caffeine consumption should be avoided for these pathologies

    Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart

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    [EN] A study has been made of the effect of chronic exercise on myocardial electrophysiological heterogeneity and stability, as well as of the role of cholinergic neurons in these changes. Determinations in hearts from untrained and trained rabbits on a treadmill were performed. The hearts were isolated and perfused. A pacing electrode and a recording multielectrode were located in the left ventricle. The parameters determined during induced VF, before and after atropine (1 mu M), were: fibrillatory cycle length (VV), ventricular functional refractory period (FRPVF), normalized energy (NE) of the fibrillatory signal and its coefficient of variation (CV), and electrical ventricular activation complexity, as an approach to myocardial heterogeneity and stability. The VV interval was longer in the trained group than in the control group both prior to atropine (78 +/- 10 vs. 68 +/- 10 ms) and after atropine (76 +/- 8 vs. 67 +/- 10 ms). Likewise, FRPVF was longer in the trained group than in the control group both prior to and after atropine (53 +/- 8 vs. 42 +/- 7 ms and 50 +/- 6 vs. 40 +/- 6 ms, respectively), and atropine did not modify FRPVF. The CV of FRPVF was lower in the trained group than in the control group prior to atropine (12.5 +/- 1.5% vs. 15.1 +/- 3.8%) and, decreased after atropine (15.1 +/- 3.8% vs. 12.2 +/- 2.4%) in the control group. The trained group showed higher NE values before (0.40 +/- 0.04 vs. 0.36 +/- 0.05) and after atropine (0.37 +/- 0.04 vs. 0.34 +/- 0.06; p = 0.08). Training decreased the CV of NE both before (23.3 +/- 2% vs. 25.2 +/- 4%; p = 0.08) and after parasympathetic blockade (22.6 +/- 1% vs. 26.1 +/- 5%). Cholinergic blockade did not modify these parameters within the control and trained groups. Activation complexity was lower in the trained than in the control animals before atropine (34 +/- 8 vs. 41 +/- 5), and increased after atropine in the control group (41 +/- 5 vs. 48 +/- 9, respectively). Thus, training decreases the intrinsic heterogeneity of the myocardium, increases electrophysiological stability, and prevents some modifications due to muscarinic block.This research was supported by the Spanish Ministry of Education and Science, (DEP2007-73234-C03-01 to AMA), http://www.mecd.gob.es/portada-mecd/; and the Generalitat Valenciana (PROMETEO 2010/093 to FJC, and FPI/2008/003 to MZ), http://www.gva.es/va/inicio/presentacion; jsessionid=ydprbDQZTsCTz85W1Such-Miquel, L.; Brines-Ferrando, L.; Alberola, A.; Zarzoso Muñoz, M.; Chorro Gasco, FJ.; Guerrero-Martínez, JF.; Parra-Giraldo, G.... (2018). Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart. 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