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Search Results: 1 - 10 of 257427 matches for " Cristina Fernández-Pérez "
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Protective effect of rifampicin and clindamycin impregnated devices against Staphylococcus spp. infection after cerebrospinal fluid diversion procedures
Raquel Gutiérrez-González, Gregorio R Boto, Cristina Fernández-Pérez, Náyade del Prado
BMC Neurology , 2010, DOI: 10.1186/1471-2377-10-93
Abstract: All shunt and EVD procedures performed by means of antibiotic-impregnated catheters (AICs) and non-AICs during the period of study were registered. In cases of shunt procedures, a minimal follow-up of 90 days was considered, as well as de novo insertion and catheter revisions. Single valve revisions were not included. In cases of EVD procedures, those catheters removed before the fifth post-insertion day were not included. A total of 119 cerebrospinal fluid shunting procedures performed with AICs were studied in comparison with 112 procedures performed by means of non-AICs.Antibiotic-impregnated catheters were associated with a significant decrease in both overall and staphylococcal infection (p = 0.030 and p = 0.045, respectively). The number needed to treat for AICs was 8 to prevent one infection and 14 to prevent one staphylococcal infection. When comparing with shunts, the use of EVDs was associated with a 37-fold increased likelihood of infection.Antibiotic-impregnated catheters are a safe and helpful tool to reduce CSF shunting device-related infections.Infection is a major complication of cerebrospinal fluid (CSF) shunting devices. It involves higher morbidity and mortality for patients but higher costs for the hospital as well [1-10]. In the last decades preventive measures have focused on surgical technique, the use of peri-operative antibiotic prophylaxis and implanted devices. Catheters coverage with antibiotics or antiseptics has been one of the latest measures to be considered [11-35]. The aim of such measure is the slow delivery of the drug along the early postoperative period (which is theoretically the moment of higher risk) in order to avoid bacterial adherence to the catheter [18,36,37]. One of the first studies in this regard was published by Gower et al. [38] in 1985. The author employed catheters soaked up in Bacitracin A for 30 minutes, which resulted in a reduction of 54% of Staphylococcus epidermidis adherence to the catheter surface.The deve
Target organ damage and cardiovascular complications in patients with hypertension and type 2 diabetes in Spain: a cross-sectional study
Luis Cea-Calvo, Pedro Conthe, Pablo Gómez-Fernández, Fernando de Alvaro, Cristina Fernández-Pérez, RICARHD investigators
Cardiovascular Diabetology , 2006, DOI: 10.1186/1475-2840-5-23
Abstract: The RICARHD study is a multicentre, cross-sectional study made by 293 investigators in Nephrology and Internal Medicine Spanish outpatient clinics, and included patients aged 55 years or more with HT and type 2 DM with more than six months of diagnosis. Demographic, clinical and biochemical data, and CVD were collected from the clinical records. Cardiac damage was defined by the presence of electrocardiographic left ventricular hypertrophy (ECG-LVH), and renal damage by a calculated glomerular filtration rate (GFR) of <60 ml/min/1.73 m2, and/or the presence of an albumin/creatinine ratio ≥ 30 mg/g; or an urinary albumin excretion (UAE) ≥ 30 mg/24 hours.2339 patients (mean age 68.9 years, 48.2% females, 51.3% with established CVD) were included. ECG-LVH was present in 22.9% of the sample, GFR <60 ml/min/1.73 m2 in 45.1%, and abnormal UAE in 58.7%. Compared with the reference patients (those without neither cardiac nor renal damage), patients with ECG-LVH alone (OR 2.20, [95%CI 1.43–3.38]), or kidney damage alone (OR 1.41, [1.13–1.75]) showed an increased prevalence of CVD. The presence of both ECG-LVH and renal damage was associated with the higher prevalence (OR 3.12, [2.33–4.19]). After stratifying by gender, this relationship was present for both, men and women.In patients with HT and type 2 DM, ECG-LVH or renal damage, evaluated using simple methods, are associated with an increased prevalence of established CVD. The simultaneous presence of both cardiac and renal damage was associated to the higher prevalence of CVD, affording complementary information. A systematic assessment of cardiac and renal damage complements the risk assessment of these patients with HT and type 2 DM.The presence of diabetes mellitus (DM) increases the risk of any form of cardiovascular disease (CVD) and of death in hypertensive patients [1]. In the natural course of arterial hypertension (HT) it moreover has been seen that the development of type 2 DM during treatment multiplies the ris
Mercury in Canned Tuna in Spain. Is Light Tuna Really Light?  [PDF]
Montserrat González-Estecha, María José Martínez-García, Manuel Fuentes-Ferrer, Andrés Bodas-Pinedo, Alfonso Calle-Pascual, José María Ordó?ez-Iriarte, Cristina Fernández-Pérez, Nieves Martell-Claros, Miguel ángel Rubio-Herrera, Emilia Gómez-Hoyos, José Jesús Guillén-Pérez
Food and Nutrition Sciences (FNS) , 2013, DOI: 10.4236/fns.2013.47A007

In Spain, certain population-based studies have shown high blood mercury (Hg) levels due to the high consumption of fish. Some studies have stated that one of the most consumed fish in Spain is canned tuna. Different Spanish organisms consider that it is safe to consume canned tuna as it supposedly has a low mercury content, particularly in so-called light tuna. However, in Spain light tuna is mainly yellowfin and bigeye tuna, while in other countries it is mainly skipjack tuna. This study analyzed 36 cans of the most popular brands in Spain and examined the influence of the type of tuna, packaging medium (olive oil, sunflower seed oil, water or marinade), different brands, prices and expiration dates. Mercury concentrations (mg/kg) were measured by atomic absorption spectrometry and thermal decomposition amalgamation. The medians observed were (mg/kg): light tuna: 0.314; IQR: 0.205 - 0.594, white tuna: 0.338; IQR: 0.276 - 0.558, skipjack: 0.311; IQR: 0.299 - 0.322, frigate tuna: 0.219; IQR 0.182 - 0.257 and mackerel: 0.042; IQR 0.029 - 0.074. We found statistically significant differences between white tuna, light tuna and mackerel (p = 0.004); light tuna and mackerel (p = 0.002) and white tuna and mackerel (p = 0.006). However, we found no differences between white tuna and light tuna, or among packaging medium, brands, prices or expiration dates. The limit of 0.500 mg/kg of mercury in canned tuna was exceeded by the following percentages of the cans: 33.3% of light tuna, 16.7% of white tuna, and 0% of Skipjack, frigate tuna and mackerel. The mercury content of the cans of Spanish light tuna that were analyzed was variable and high. The results of this study indicate that stricter regulation of Hg in canned tuna is necessary. Until then, it is safer to recommend that vulnerable populations such as children and pregnant women consume canned mackerel, which has a markedly lower mercury content.

Promoción de hábitos saludables en escolares de Hermosillo, Sonora, México Promote healthy habits in scholars from Hermosillo, Sonora, México
Elba Abril-Valdez,Cristina Rascón-Loreto,Pastor Bonilla-Fernández,Héctor Hernández-Pérez
Revista Cubana de Higiene y Epidemiología , 2012,
Abstract: Objetivo: ejecución y análisis de una intervención educativa con la finalidad incrementar conocimientos y hábitos saludables en escolares. Métodos: dise o cuasi experimental. Se trabajó con el total de alumnos inscritos de una escuela pública de nivel primaria de Hermosillo, Sonora. Se dise aron y realizaron cinco módulos basados en la propuesta pedagógica del constructivismo: alimentación e higiene, autoestima, tabaquismo y adicciones, cultura por la paz y cuidado del medio ambiente. Las actividades se realizaron en sesiones semanales de una hora con cada grupo. Se aplicó una medición pre y pos intervención para ver cambios en los conocimientos. Resultados: los escolares incrementaron conocimientos en los diversos ejes temáticos, mejoraron su autoestima y algunas prácticas relacionadas con la alimentación y su entorno. Conclusión: es necesaria la continuidad de este tipo de acciones escolares para incidir de manera integral en las fases tempranas del desarrollo cognitivo del escolar y buscar contextualizar los componentes social, cultural y económico incorporando la participación de padres y maestros para garantizar la sustentabilidad. Objective: analysis and execution of an educative intervention with the purpose to promote, develop, and improve knowledge and healthy habits in students. Methods: a cuasi experimental design. This study included all the students registered in an elementary public school from Hermosillo, Sonora. Five modules were designed according to principles of constructivism: meals and hygiene, self esteem, smoking habits and addictions, culture for peace, environment care, and they were applied. The activities were carried out by a health promoter in an hour- session weekly per each group. An evaluation was given pre and post intervention in order to measure any changes in knowledge. Results: scholars' knowledge increased about these different topics, their self esteem increased, and some practices related to meals and their environment improved. Conclusion: it is necessary to continue this kind of practice in order for achieving an integral effect on the early cognitive development stages of students and for contextualizing the social, cultural, and economic components incorporating the participation of teachers and parents in order to guarantee the sustainability.
On Normal Forms for Levi-flat hypersurfaces with an Isolated Line Singularity
Arturo Fernández-Pérez
Mathematics , 2013, DOI: 10.1007/s11512-014-0198-3
Abstract: We prove the existence of normal forms for some local real-analytic Levi-flat hypersurfaces with an isolated line singularity. We also give sufficient conditions for that a Levi-flat hypersurface with a complex line as singularity to be a pullback of a real-analytic curve in C via a holomorphic function.
On Normal Forms of Singular Levi-Flat Real Analytic Hypersurfaces
Arturo Fernández-Pérez
Mathematics , 2010, DOI: 10.1007/s00574-011-0004-9
Abstract: Let $F(z)=\mathcal{R}e(P(z)) + h.o.t$ be such that $M=(F=0)$ defines a germ of real analytic Levi-flat at $0\in\mathbb{C}^{n}$, $n\geq{2}$, where $P(z)$ is a homogeneous polynomial of degree $k$ with an isolated singularity at $0\in\mathbb{C}^{n}$ and Milnor number $\mu$. We prove that there exists a holomorphic change of coordinate $\phi$ such that $\phi(M)=(\mathcal{R}e(h)=0)$ where $h(z)$ is a polynomial of degree $\mu+1$ and $j^{k}_{0}(h)=P$.
On Levi-flat hypersurfaces tangent to holomorphic webs
Arturo Fernández-Pérez
Mathematics , 2011,
Abstract: We investigate germs of real analytic Levi-flat hypersurfaces tangent to germs of codimension one holomorphic webs. We introduce the notion of first integrals for local webs. In particular, we prove that a $k$-web with finitely many invariant analytic subvarieties through the origin tangent to a Levi-flat hypersurface has a holomorphic first integral.
Influence of Vitamin D-Related Gene Polymorphisms (CYP27B and VDR) on the Response to Interferon/Ribavirin Therapy in Chronic Hepatitis C
Elena García-Martín, José A. G. Agúndez, María L. Maestro, Avelina Suárez, Marta Vidaurreta, Carmen Martínez, Cristina Fernández-Pérez, Luis Ortega, José M. Ladero
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0074764
Abstract: Background and Aims Vitamin D exerts immunomodulatory effects on the host response against infection with hepatitis C virus (HCV). This study was performed to assess the putative influence of polymorphisms in vitamin D-related genes on the response to antiviral therapy in patients with chronic hepatitis C (CHC). Methods Single nucleotide polymorphisms (SNPs) in CYP27B-1260 gene promoter (rs10877012AC) and in vitamin D receptor (VDR) gene rs2228570TC, rs1544410CT, rs7975232AC and rs731236AT were analyzed in a cohort of 238 Caucasian CHC patients treated with pegylated interferon (Peg-IFN) plus ribavirin (RBV). Multivariate analyses were performed to exclude confounding effects of well-known baseline predictors of response to therapy (HCV genotype and load, IL28B genotype, age, and GGT and serum cholesterol). Results Three SNPs at the VDR gene (rs1544410, rs7975232 and rs731236) were in strong linkage disequilibrium, with the CCA haplotype predicting therapeutic failure [Odds ratio 2.743; (95% C.I. 1.313–5.731), p = 0.007]. The carrier state of the VDR rs2228570 T allele was inversely related to the probability of therapeutic failure [Odds ratio 0.438; 95 C.I. (0.204–0.882), p = 0.021]. No relation existed between CYP27B-1260 rs10877012 polymorphism and response to therapy. The area under the operating curve (AUROC) based on the model including all variables significantly related to the response to therapy was 0.846 (95% confidence interval = 0.793–0.899). Conclusion VDR gene polymorphisms are independently related to the response to Peg-IFN+RBV therapy in chronic hepatitis C and could be used as complementary biomarkers of response when included in a prediction algorithm in association with demographic, virologic, biochemical and genetic traits.
Genetic Algorithm for Arbitrage with More than Three Currencies  [PDF]
Adrián Fernández-Pérez, Fernando Fernández-Rodríguez, Simón Sosvilla-Rivero
Technology and Investment (TI) , 2012, DOI: 10.4236/ti.2012.33025
Abstract: We develop a genetic algorithm that is able to find the optimal sequence of exchange rates that maximizes arbitrage profits with more than three currencies, being both the triangular arbitrage and the direct exchange rate two special cases of the proposed algorithm. Applying the algorithm to the most traded currencies, we find average profits ranking from 4.5083% to 0.3162% for changing 1 USD for EUR with respect to the direct exchange rate, for different transaction costs, during the period October 2000-April 2012. Our results also suggest that the arbitrage profits increased just after the subprime crisis in summer of 2007 and that they are higher when the market is less liquid.
Propiedades físico-mecánicas de algunas maderas nativas chilenas coníferas y latifoliadas por ultrasonido Physical and mechanical properties of some chilean softwoods and hardwoods using ultrasound
Erik Baradit,Peter Niemz,Arturo Fernández-Pérez
MADERAS : Ciencia y Tecnología , 2013,
Abstract: La utilización de técnicas no destructivas juega un papel importante y complementario en los procesos de caracterización de la madera. En este trabajo el objetivo fue evaluar algunas propiedades físico-mecánicas de maderas nativas chilenas por medio de ultrasonido y compararlas con ensayos mecánicos tradicionales de flexión. Las maderas seleccionadas fueron cuatro latifoliadas: tepa (Laureliopsis philipiana), olivillo (Aextoxicon punctatum), laurel (Laurelia sempervirens) y lenga (Nothofagus pumilio), y dos coníferas: alerce (Fitzroya cupressoides) y ma ío (Podocarpus nubigena). Para ésto, se utilizaron los equipos de ultrasonido Steinkamp BP5 y Panametric Epoch XT. Los resultados mostraron mayor anisotropía elástica para las latifoliadas que para las coníferas y una relativa simetría en las velocidades de propagación transversal y los módulos de corte a lo largo de las tres principales direcciones del árbol. También los valores medios de los módulos de elasticidad calculados por ultrasonido resultaron entre 25 y 47 % más altos que los medidos por ensayos mecánicos. The non-destructive techniques are a very important tool in the process of wood characterization and evaluation. In this work, the objective is the evaluation of physical and mechanical properties of some native Chilean wood species by using the ultrasound techniques and their comparision with the results of typical mechanical tests. The selected woods were four hardwoods: tepa (Laureliopsis philipiana), olivillo (Aextoxicon punctatum), laurel (Laurelia sempervirens) and lenga (Nothofagus pumilio) and two softwoods: alerce (Fitzroya cupressoides) and ma ío (Podocarpus nubigena). The equipment used were two types of ultrasound generators: Steinkamp BP5 and Panametric Epoch XT. The results shown a higher anisotropy for hardwoods than for softwoods, and a relatively symmetry for transversal wave propagation velocities and for shear moduli of elasticity, along the principal directions of the tree. At the same time the mean values of Young moduli of elasticity (MOE) obtained by using the ultrasound equipments were a 25-47 % higher than the same moduli measured by mechanical tests.
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