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Search Results: 1 - 10 of 208634 matches for " Jose Luis de la Pompa "
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Notch Is a Critical Component of the Mouse Somitogenesis Oscillator and Is Essential for the Formation of the Somites
Zoltan Ferjentsik,Shinichi Hayashi equal contributor,J. Kim Dale equal contributor,Yasumasa Bessho,An Herreman,Bart De Strooper,Gonzalo del Monte,Jose Luis de la Pompa,Miguel Maroto
PLOS Genetics , 2009, DOI: 10.1371/journal.pgen.1000662
Abstract: Segmentation of the vertebrate body axis is initiated through somitogenesis, whereby epithelial somites bud off in pairs periodically from the rostral end of the unsegmented presomitic mesoderm (PSM). The periodicity of somitogenesis is governed by a molecular oscillator that drives periodic waves of clock gene expression caudo-rostrally through the PSM with a periodicity that matches somite formation. To date the clock genes comprise components of the Notch, Wnt, and FGF pathways. The literature contains controversial reports as to the absolute role(s) of Notch signalling during the process of somite formation. Recent data in the zebrafish have suggested that the only role of Notch signalling is to synchronise clock gene oscillations across the PSM and that somite formation can continue in the absence of Notch activity. However, it is not clear in the mouse if an FGF/Wnt-based oscillator is sufficient to generate segmented structures, such as the somites, in the absence of all Notch activity. We have investigated the requirement for Notch signalling in the mouse somitogenesis clock by analysing embryos carrying a mutation in different components of the Notch pathway, such as Lunatic fringe (Lfng), Hes7, Rbpj, and presenilin1/presenilin2 (Psen1/Psen2), and by pharmacological blocking of the Notch pathway. In contrast to the fish studies, we show that mouse embryos lacking all Notch activity do not show oscillatory activity, as evidenced by the absence of waves of clock gene expression across the PSM, and they do not develop somites. We propose that, at least in the mouse embryo, Notch activity is absolutely essential for the formation of a segmented body axis.
Proteomic Analysis of Circulating Monocytes Identi es Cathepsin D as A Potential Novel Plasma Marker of Acute Coronary Syndromes
Maria G. Barderas,Verónica M. Dardé,Fernando de la Cuesta,Jose Luis Martin-Ventura
Clinical Medicine : Cardiology , 2008,
Abstract: We have performed a proteomic analysis of peripheral blood monocytes from ACS patients in comparison with healthy subjects and stable coronary patients in order to search novel biomarkers of ACS in circulating monocytes. Monocytes were isolated from blood of patients with non-ST elevation ACS (n = 27) at day 0, 2 and 6 months, and from patients with stable coronary disease (n = 10) and matched healthy controls (n = 11). The proteomic analysis of monocytes from ACS patients at day 0 showed that cathepsin D is differentially expressed compared to healthy subjects and stable coronary patients. Western blot analysis indicated that the mature form of cathepsin D at day 0 was overexpressed in monocytes of ACS patients in relation to healthy subjects. In contrast, the precursor of this enzyme, absent at day 0 in ACS patients, was highly expressed in monocytes of healthy subjects. Furthermore, the upregulation of the mature form of cathepsin D diminished along the time, while the expression of the precursor increased. ACS patients also showed significantly increased plasma cathepsin D levels on admission compared to healthy subjects and stable patients. Cathepsin D plasma levels diminished at 2 and 6 months to control values. Finally, cathepsin D levels were independent of the existence of coronary risk factors and CRP levels, correlating only with CD40L. Since this protease participates in the genesis and rupture of atherosclerotic plaques, it could represent a potential marker of ACS.
Advice from a Medical Expert through the Internet on Queries about AIDS and Hepatitis: Analysis of a Pilot Experiment
Javier Marco ,Raquel Barba,Juan E Losa,Carlos Martínez de la Serna,María Sainz,Isabel Fernández Lantigua,Jose Luis de la Serna
PLOS Medicine , 2006, DOI: 10.1371/journal.pmed.0030256
Abstract: Background Advice from a medical expert on concerns and queries expressed anonymously through the Internet by patients and later posted on the Web, offers a new type of patient–doctor relationship. The aim of the current study was to perform a descriptive analysis of questions about AIDS and hepatitis made to an infectious disease expert and sent through the Internet to a consumer-oriented Web site in the Spanish language. Methods and Findings Questions were e-mailed and the questions and answers were posted anonymously in the “expert-advice” section of a Web site focused on AIDS and hepatitis. We performed a descriptive study and a temporal analysis of the questions received in the first 12 months after the launch of the site. A total of 899 questions were received from December 2003 to November 2004, with a marked linear growth pattern. Questions originated in Spain in 68% of cases and 32% came from Latin America (the Caribbean, Central America, and South America). Eighty percent of the senders were male. Most of the questions concerned HIV infection (79%) with many fewer on hepatitis (17%) . The highest numbers of questions were submitted just after the weekend (37% of questions were made on Mondays and Tuesdays). Risk factors for contracting HIV infection were the most frequent concern (69%), followed by the window period for detection (12.6%), laboratory results (5.9%), symptoms (4.7%), diagnosis (2.7%), and treatment (2.2%). Conclusions Our results confirm a great demand for this type of “ask-the-expert” Internet service, at least for AIDS and hepatitis. Factors such as anonymity, free access, and immediate answers have been key factors in its success.
Comparison of Different Methods for the Experimental Antenna Phase Center Determination Using a Planar Acquisition System
Pablo Padilla de la Torre;Jose-Manuel Fernandez Gonzalez;Jose Luis Padilla;Gonzalo Exposito-Dominguez;Manuel Sierra-Castaner;Belen Galocha Iraguen
PIER , 2013, DOI: 10.2528/PIER12112108
Abstract: This work provides the comparison of different methods for the experimental determination of the phase center location of an antenna. The phase center position is determined by means of measured data obtained with a planar scanning system and computed with different methods: a least squares fit method with and without weighting coefficients and a directivity-based plane wave spectrum (PWS) analysis method. A study of the phase center position for different microwave antennas is provided. The results of the different methods are presented and compared, along with the confidence interval of the phase center values due to the uncertainties of the acquisition system.
Nano-Scale Au Supported on Carbon Materials for the Low Temperature Water Gas Shift (WGS) Reaction
Sonia Gil,Amaya Romero,Antonio de Lucas,Paula Sánchez,Fernando Dorado,Ana Raquel de la Osa,Jesús Manuel García-Vargas,Jose Luis Valverde
Catalysts , 2011, DOI: 10.3390/catal1010155
Abstract: Au-based catalysts supported on carbon materials with different structures such as graphite (G) and fishbone type carbon nanofibers (CNF-F) were prepared using two different methods (impregnation and gold-sol) to be tested in the water gas shift (WGS) reaction. Atomic absorption spectrometry, transmission electron microscopy (TEM), temperature-programmed oxidation (TPO), X-ray diffraction (XRD), Raman spectroscopy, elemental analyses (CNH), N 2 adsorption-desorption analysis, temperature-programmed reduction (TPR) and temperature-programmed decomposition were employed to characterize both the supports and catalysts. Both the crystalline nature of the carbon supports and the method of gold incorporation had a strong influence on the way in which Au particles were deposited on the carbon surface. The higher crystallinity and the smaller and well dispersed Au particle size were, the higher activity of the catalysts in the WGS reaction was noted. Finally, catalytic activity showed an important dependence on the reaction temperature and steam-to-CO molar ratio.
Litiasis renal en pacientes con hiperparatiroidismo primario: Evolución y tratamiento
Valle Díaz de la Guardia,Francisco; Arrabal Martín,Miguel; Arrabal Polo,Miguel ángel; Quirosa Flores,Susana; Miján Ortiz,Jose Luis; Zuluaga Gómez,Armando;
Archivos Espa？oles de Urología (Ed. impresa) , 2010, DOI: 10.4321/S0004-06142010000100005
Abstract: objectives: the relationship between hyperparathyroidism and lithiasis is quite known, so the study of parathyroid glands is especially mandatory in the face of relapses. our objective is to analyze both primary hyperparathyroidism (phpt) associated with renal lithiasis and the evolution of this condition after parathyroidectomy, as well as to study factors associated with the presence of lithiasis or bone pathology, and carry out a review on bibliography. methods: we describe a retrospective study of a series comprising 287 cases of hyperparathyroidism: 237 of them were primary and the remaining 50, secondary. we have included: sex, age, evolution time and symptoms, diagnostic tests (biochemical, radiological and histological). factors such as number of episodes prior to diagnosis and treatments were analyzed in patients with symptomatic lithiasis to know whether patients exhibited residual lithiasis after the management of calculi or whether patients underwent episodes after parathyroidectomy, or whether or not they were treated. statistical analysis was carried out through spss 15.0 for windows. results: forty five percent of the patients had suffered lithiasis episodes; 50%, osteopenia/osteoporosis; 23%, musculoskeletal pain; 23%, asthenia and/or depressive syndrome. in 13.5% of cases, diagnosis was supported by the presence of hypercalcemia; no other symptoms were detected. we have analyzed factors that favor or inhibit renal lithiasis formation and compared biochemical parameters from the group of primary hyperthyroidism that exhibited lithiasis (41 patients) with those patients who did not (49). we noted that lithiasis patients showed higher values of calcium, alkaline phosphatase, intact pth, mean pth, osteocalcin, and chlorine/phosphate, calciuria and phosphaturia indexes. student's t test on two independent samples revealed significant statistical differences in calcium levels (p<0.05), intact pth (<0.05) and osteocalcin. conclusions: primary hyperparathyr
Reparación microquirúrgica de las lesiones traumáticas del nervio cubital
LAZO DE LA OSA,MAITE; MARRERO RIVERON,LUIS OSCAR; CABRERA VILTRES,NELSON; REMON DAVILA,XIOMARA; GUERRERO RODRíGUEZ,JOSE A.; ROCHE EGüES,HILDA ELENA;
Revista Cubana de Ortopedia y Traumatolog？-a , 1996,
Abstract: 31 patients with traumatic injuries of the ulnar nerve received surgical treatment in our center from january, 1988 to december, 1992. these injuries were more frequent among the male patients and at the ages from 15 to 44. the best results were obtained in the injuries repaired before the six months of occurrence and where the nervous interfascicular graft was used as a surgical technique.
Pathogenesis of occult chronic hepatitis B virus infection
Rocio Aller de la Fuente, María L Gutiérrez, Javier Garcia-Samaniego, Conrado Fernández-Rodriguez, Jose Luis Lledó, Gregorio Castellano
World Journal of Gastroenterology , 2011,
Abstract: Occult hepatitis B infection (OBI) is characterized by hepatitis B virus (HBV) DNA in serum in the absence of hepatitis B surface antigen (HBsAg) presenting HBsAg-negative and anti-HBc positive serological patterns. Occult HBV status is associated in some cases with mutant viruses undetectable by HBsAg assays; but more frequently it is due to a strong suppression of viral replication and gene expression. OBI is an entity with world-wide diffusion. The failure to detect HBsAg, despite the persistence of the viral DNA, is due in most cases to the strong suppression of viral replication and gene expression that characterizes this “occult” HBV infection; although the mechanisms responsible for suppression of HBV are not well understood. The majority of OBI cases are secondary to overt HBV infection and represent a residual low viremia level suppressed by a strong immune response together with histological derangements which occurred during acute or chronic HBV infection. Much evidence suggests that it can favour the progression of liver fibrosis and the development of hepatocellular carcinoma.
Predicción del Ajuste Diádico en una Muestra Nuevoleonesa
Jose Moral de la Rubia
Revista Interamericana de Psicología , 2008,
Abstract: El objetivo del presente estudio es predecir el ajuste diádico con variables sociodemográficas, religiosas, sexuales, de estados emocionales y personalidad. La muestra consta de 100 parejas casadas. Como instrumento de medida se emplea un cuestionario integrado por preguntas cerradas y escalas para medir ajuste diádico, satisfacción sexual, alexitimia, ansiedad, depresión, afectos positivos y negativos, deseabilidad social y engrandecimiento marital. Los datos se analizan por correlación, análisis factorial y regresión. El ajuste diádico se asocia con el engrandecimiento marital, ansiedad-rasgo, satisfacción sexual; con alexitimia y depresión especialmente en hombres; y con menor fuerza, con niveles bajos de afectos negativos y altos de positivos. Al factorizar los correlatos interrelacionados del ajuste diádico surge un factor de neuroticismo y emociones negativas que es el principal predictor de falta de ajuste. Se considera que el engrandecimiento marital se debe interpretar como autoenga o y enamoramiento mejor que como manejo de la impresión.
Effect of homogenization process on the hardness of Zn–Al–Cu alloys
Jose D. Villegas-Cardenas,Maribel L. Saucedo-Mu？oz,Victor M. Lopez-Hirata,Antonio De Ita-De la Torre,Erika O. Avila-Davila,Jorge Luis Gonzalez-Velazquez
- , 2015, DOI: https://doi.org/10.1007/s12613-015-1170-3
Abstract: The effect of a homogenizing treatment on the hardness of as-cast Zn–Al–Cu alloys was investigated. Eight alloy compositions were prepared and homogenized at 350 °C for 180 h, and their Rockwell “B” hardness was subsequently measured. All the specimens were analyzed by X-ray diffraction and metallographically prepared for observation by optical microscopy and scanning electron microscopy. The results of the present work indicated that the hardness of both alloys (as-cast and homogenized) increased with increasing Al and Cu contents; this increased hardness is likely related to the presence of the θ and τ′ phases. A regression equation was obtained to determine the hardness of the homogenized alloys as a function of their chemical composition and processing parameters, such as homogenization time and temperature, used in their preparation.
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