39 resultados para Rodríguez, Alberto


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Esta memoria describe el desarrollo de una aplicación de mapas para Internet (SIG Web). Dicha aplicación consistirá en gestionar el inventario de presiones de la Confederación Hidrográfica de Tajo.

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Background: Aproximately 5–10% of cases of mental retardation in males are due to copy number variations (CNV) on the X chromosome. Novel technologies, such as array comparative genomic hybridization (aCGH), may help to uncover cryptic rearrangements in X-linked mental retardation (XLMR) patients. We have constructed an X-chromosome tiling path array using bacterial artificial chromosomes (BACs) and validated it using samples with cytogenetically defined copy number changes. We have studied 54 patients with idiopathic mental retardation and 20 controls subjects. Results: Known genomic aberrations were reliably detected on the array and eight novel submicroscopic imbalances, likely causative for the mental retardation (MR) phenotype, were detected. Putatively pathogenic rearrangements included three deletions and five duplications (ranging between 82 kb to one Mb), all but two affecting genes previously known to be responsible for XLMR. Additionally, we describe different CNV regions with significant different frequencies in XLMR and control subjects (44% vs. 20%). Conclusion:This tiling path array of the human X chromosome has proven successful for the detection and characterization of known rearrangements and novel CNVs in XLMR patients.

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Background: Germline genetic variation is associated with the differential expression of many human genes. The phenotypic effects of this type of variation may be important when considering susceptibility to common genetic diseases. Three regions at 8q24 have recently been identified to independently confer risk of prostate cancer. Variation at 8q24 has also recently been associated with risk of breast and colorectal cancer. However, none of the risk variants map at or relatively close to known genes, with c-MYC mapping a few hundred kilobases distally. Results: This study identifies cis-regulators of germline c-MYC expression in immortalized lymphocytes of HapMap individuals. Quantitative analysis of c-MYC expression in normal prostate tissues suggests an association between overexpression and variants in Region 1 of prostate cancer risk. Somatic c-MYC overexpression correlates with prostate cancer progression and more aggressive tumor forms, which was also a pathological variable associated with Region 1. Expression profiling analysis and modeling of transcriptional regulatory networks predicts a functional association between MYC and the prostate tumor suppressor KLF6. Analysis of MYC/Myc-driven cell transformation and tumorigenesis substantiates a model in which MYC overexpression promotes transformation by down-regulating KLF6. In this model, a feedback loop through E-cadherin down-regulation causes further transactivation of c-MYC.Conclusion: This study proposes that variation at putative 8q24 cis-regulator(s) of transcription can significantly alter germline c-MYC expression levels and, thus, contribute to prostate cancer susceptibility by down-regulating the prostate tumor suppressor KLF6 gene.

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ADSL is becoming the standard form of residential and small-business broadband Internet access due to, primarily, its low deployment cost. These ADSL residential lines are often deployed with 802.11 Access Points (AP) that providewireless connectivity. Given the density of ADSL deployment, it is often possible for a residential wireless client to be in range of several other APs, belonging to neighbors, with ADSL connectivity. While the ADSL technology has showed evident limits in terms of capacity (with speeds ranging 1-10 Mbps), the short-range wireless communication can guarantee a muchhigher capacity (up to 20 Mbps). Furthermore, the ADSL links in the neighborhood are generally under-utilized, since ADSL subscribers do not connect 100% of the time. Therefore, it is possible for a wireless client to simultaneously connect to several APs in range and effectively aggregate their available ADSL bandwidth.In this paper, we introduce ClubADSL, a wireless client that can simultaneously connect to several APs in range on different frequencies and aggregate both their downlink and uplink capacity. ClubADSL is a software that runs locally on the client-side, and it requires neither modification to the existing Internet infrastructure, nor any hardware/protocol upgradesto the 802.11 local area network. We show the feasibility of ClubADSL in seamlessly transmitting TCP traffic, and validate its implementation both in controlled scenarios and with current applications over real ADSL lines. In particular we show that a ClubADSL client can greatly benefit from the aggregated download bandwidth in the case of server-client applications such as video streaming, but can also take advantage of the increased upload bandwidth greatly reducing download times with incentive-based P2P applications such as BitTorrent.

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Los más viejos del lugar recordarán con nostalgia los repertorios clásicos de fuentes de información elaborados por Malclès y Sabor... A los no tan viejos les sonarán los nombres de Sheehy (o Balay) y Walford

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Control of cell cycle progression by stress-activated protein kinases (SAPKs) is essential for cell adaptation to extracellular stimuli. The Schizosaccharomyces pombe SAPK Sty1/Spc1 orchestrates general changes in gene expression in response to diverse forms of cytotoxic stress. Here we show that Sty1/Spc1 is bound to its target, the Srk1 kinase, when the signaling pathway is inactive. In response to stress, Sty1/Spc1 phosphorylates Srk1 at threonine 463 of the regulatory domain, inducing both activation of Srk1 kinase, which negatively regulates cell cycle progression by inhibiting Cdc25, and dissociation of Srk1 from the SAPK, which leads to Srk1 degradation by the proteasome.

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Este libro es un nuevo fascículo del volumen I del proyecto CSIR-España, que a modo de corpus reúne, con carácter general y de modo minuciosamente sistemático, los sarcófagos romanos decorados de Andalucía, cuyo mayor número ya había sido objeto de publicación. La investigación histórica e iconográfica sobre los sarcófagos hispanos (en especial para los ejemplares paleocristianos) es deudora fundamentalmente de los estudios realizados por Sotomayor (1966: 77-99; 1975) y, más recientemente, por Koch (2000), además de dos de los autores que firman este trabajo, que en los últimos años se han detenido metódicamente sobre los sarcófagos béticos de tema profano (Beltrán, 1999; Rodríguez Oliva, 2001: 107-127).

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In this work, the calcium-induced aggregation of phosphatidylserine liposomes is probed by means of the analysis of the kinetics of such process as well as the aggregate morphology. This novel characterization of liposome aggregation involves the use of static and dynamic light-scattering techniques to obtain kinetic exponents and fractal dimensions. For salt concentrations larger than 5 mM, a diffusion-limited aggregation regime is observed and the Brownian kernel properly describes the time evolution of the diffusion coefficient. For slow kinetics, a slightly modified multiple contact kernel is required. In any case, a time evolution model based on the numerical resolution of Smoluchowski's equation is proposed in order to establish a theoretical description for the aggregating system. Such a model provides an alternative procedure to determine the dimerization constant, which might supply valuable information about interaction mechanisms between phospholipid vesicles.

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The aim of this study was to evaluate the tissue compatibility of a silorane-based resin system (FiltekTM Silorane) and a methacrylatebased nanoparticle resin (FiltekTM Supreme XT) after implantation in the subcutaneous connective tissue of isogenic mice. One hundred and thirty five male isogenic BALB/c mice were randomly assigned to 12 experimental and 3 control groups, according to the implanted material and the experimental period of 7, 21 and 63 days. At the end of each period, the animals were killed and the tubes with the surrounding tissues were removed and processed for microscopic analysis. Samples were subjected to a descriptive and a semi-quantitative analyses using a 4-point scoring system (0-3) to evaluate the collagen fiber formation and inflammatory infiltrate. Data were statistically analyzed using the Kruskal Wallis test (a=0.05). The results showed that there was no significant difference between the experimental and control groups considering the three evaluation periods (p>0.05). The silorane-based and the methacrylate-based nanoparticle resins presented similar tissue response to that of the empty tube (control group) after subcutaneous implantation in isogenic mice.

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Anàlisi dels processos de transició des d'una situació, en la que s'han produït violacions dels drets humans, fins a un sistema democràtic, des del punt de vista de la justícia aplicada, que castiga els transgressors, porta la reparació a les víctimes i possibilita una reconciliació de la societat, que fonamenti i garanteixi l'estabilitat i continuïtat del nou sistema democràtic.

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We hypothesized that platelet-activating factor (PAF), a potent inflammatory mediator, could induce gas exchange abnormalities in normal humans. To this end, the effect of aerosolized PAF (2 mg/ml solution; 24 micrograms) on ventilation-perfusion (VA/Q) relationships, hemodynamics, and resistance of the respiratory system was studied in 14 healthy, nonatopic, and nonsmoking individuals (23 +/- 1 [SEM]yr) before and at 2, 4, 6, 8, 15, and 45 min after inhalation, and compared to that of inhaled lyso-PAF in 10 other healthy individuals (24 +/- 2 yr). PAF induced, compared to lyso-PAF, immediate leukopenia (P < 0.001) followed by a rebound leukocytosis (P < 0.002), increased minute ventilation (P < 0.05) and resistance of the respiratory system (P < 0.01), and decreased systemic arterial pressure (P < 0.05). Similarly, compared to lyso-PAF, PaO2 showed a trend to fall (by 12.2 +/- 4.3 mmHg, mean +/- SEM maximum change from baseline), and arterial-alveolar O2 gradient increased (by 16.7 +/- 4.3 mmHg) (P < 0.02) after PAF, because of VA/Q mismatch: the dispersion of pulmonary blood flow and that of ventilation increased by 0.45 +/- 0.1 (P < 0.01) and 0.29 +/- 0.1 (P < 0.04), respectively. We conclude that in normal subjects, inhaled PAF results in considerable immediate VA/Q inequality and gas exchange impairment. These results reinforce the notion that PAF may play a major role as a mediator of inflammation in the human lung.

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We hypothesized that platelet-activating factor (PAF), a potent inflammatory mediator, could induce gas exchange abnormalities in normal humans. To this end, the effect of aerosolized PAF (2 mg/ml solution; 24 micrograms) on ventilation-perfusion (VA/Q) relationships, hemodynamics, and resistance of the respiratory system was studied in 14 healthy, nonatopic, and nonsmoking individuals (23 +/- 1 [SEM]yr) before and at 2, 4, 6, 8, 15, and 45 min after inhalation, and compared to that of inhaled lyso-PAF in 10 other healthy individuals (24 +/- 2 yr). PAF induced, compared to lyso-PAF, immediate leukopenia (P < 0.001) followed by a rebound leukocytosis (P < 0.002), increased minute ventilation (P < 0.05) and resistance of the respiratory system (P < 0.01), and decreased systemic arterial pressure (P < 0.05). Similarly, compared to lyso-PAF, PaO2 showed a trend to fall (by 12.2 +/- 4.3 mmHg, mean +/- SEM maximum change from baseline), and arterial-alveolar O2 gradient increased (by 16.7 +/- 4.3 mmHg) (P < 0.02) after PAF, because of VA/Q mismatch: the dispersion of pulmonary blood flow and that of ventilation increased by 0.45 +/- 0.1 (P < 0.01) and 0.29 +/- 0.1 (P < 0.04), respectively. We conclude that in normal subjects, inhaled PAF results in considerable immediate VA/Q inequality and gas exchange impairment. These results reinforce the notion that PAF may play a major role as a mediator of inflammation in the human lung.

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Erythropoietin (rHuEPO) has proven to be effective in the treatment of anemia of chronic renal failure (CRF). Despite improving the quality of life, peak oxygen uptake after rHuEPO therapy is not improved as much as the increase in hemoglobin concentration ([Hb)] would predict. We hypothesized that this discrepancy is due to failure of O2 transport rates to rise in a manner proportional to [Hb]. To test this, eight patients with CRF undergoing regular hemodialysis were studied pre- and post-rHuEPO ([Hb] = 7.5 +/- 1.0 vs. 12.5 +/- 1.0 g x dl-1) using a standard incremental cycle exercise protocol. A group of 12 healthy sedentary subjects of similar age and anthropometric characteristics served as controls. Arterial and femoral venous blood gas data were obtained and coupled with simultaneous measurements of femoral venous blood flow (Qleg) by thermodilution to obtain O2 delivery and oxygen uptake (VO2). Despite a 68% increase in [Hb], peak VO2 increased by only 33%. This could be explained largely by reduced peak leg blood flow, limiting the gain in O2 delivery to 37%. At peak VO2, after rHuEPO, O2 supply limitation of maximal VO2 was found to occur, permitting the calculation of a value for muscle O2 conductance from capillary to mitochondria (DO2). While DO2 was slightly improved after rHuEPO, it was only 67% of that of sedentary control subjects. This kept maximal oxygen extraction at only 70%. Two important conclusions can be reached from this study. First, the increase in [Hb] produced by rHuEPO is accompanied by a significant reduction in peak blood flow to exercising muscle, which limits the gain in oxygen transport. Second, even after restoration of [Hb], O2 conductance from the muscle capillary to the mitochondria remains considerably below normal.