114 research outputs found

    Direct interaction between RecA and a CheW-like protein is required for surface-associated motility, chemotaxis and the full virulence of Acinetobacter baumannii strain ATCC 17978

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    Acinetobacter baumannii is a nosocomial pathogen that causes multi-drug resistant infections mainly in immunocompromised patients. Although this gram-negative species lacks flagella, it is able to move over wet surfaces through a not well characterized type of movement known as surface-associated motility. In this study we demonstrate through the inactivation of the A1S_2813 gene (coding a CheW-like protein) and recA (coding a DNA damage repair and recombination protein) that both genes are involved in the surface-associated motility and chemotaxis of A. baumannii ATCC 17978 strain. In addition, we also point out that the lack of either RecA or CheW-like proteins reduces its virulence in the Caenorhabditis elegans and the Galleria mellonella animal models. Furthermore, we show through co-immunoprecipitation assays that the CheW-like protein and RecA interact and that this interaction is abolished by the introduction of the mutation S97A in one of the domains of CheW-like protein that is structurally conserved in Salmonella enterica and necessary for the RecA-CheW interaction in this bacterial species. Finally, we show that the replacement of the wild-type CheW-like protein by that presenting the S97A mutation impairs surface-associated motility, chemotaxis and virulence of A. baumannii strain ATCC 17978

    Los siete sabios de Roma en España (siglos XV-XX). Estudio y edición

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    La presente tesis doctoral se fundamenta en la consecución de dos objetivos: estudiar la difusión de la Historia de los siete sabios de Roma en España desde la primera traducción conservada y salida de las prensas zaragozanas de los hermanos Hurus hasta su impresión en pliegos de cordel en los siglos XIX y XX, y analizar las transformaciones sufridas por esta en su forma, formato y contenido a lo largo de todos estos siglos. La investigación toma como punto de partida los estudios parciales que se han desarrollado hasta ahora en torno al corpus de textos que conforman la «narrativa caballeresca breve», y que demuestran que un gran número obras gestadas o traducidas en los dos últimos siglos del periodo medieval supieron valerse de la imprenta como medio de supervivencia gracias a la mediación de la labor de una serie de tipógrafos movidos por los beneficios comerciales. Para ello, se toma como punto de partida la génesis y constitución del ciclo occidental de los Siete sabios de Roma para centrar la atención en la anónima traducción Historia de los siete sabios de Roma. De este texto se ofrece un profundo estudio sobre su paso por la imprenta hasta su reescritura en el siglo XIX. En este recorrido se aborda no solo la materialidad de las ediciones, sino todo el entramado que rodeó a su difusión, y que incluye las modificaciones textuales y los distintos lectores que pudieron tener la obra en sus manos. En última instancia, se pretende demostrar que el éxito editorial de la obra en la imprenta se debió a su capacidad para adaptarse a los distintos contextos de recepción. El estudio se completa con una edición crítica que transcribe y pone en común todos los testimonios conservados de la obra en cuatrocientos años y el texto que muestran los pliegos de cordel decimonónicos.<br /

    Impact of the COVID-19 Pandemic on Inappropriate Use of the Emergency Department

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    Background: Inappropriate use of the emergency department (IEDU)—consisting of the unnecessary use of the resource by patients with no clinical need—is one of the leading causes of the loss of efficiency of the health system. Specific contexts modify routine clinical practice and usage patterns. This study aims to analyse the influence of COVID-19 on the IEDU and its causes. Methods: A retrospective, cross-sectional study conducted in the emergency department of a high-complexity hospital. The Hospital Emergency Suitability Protocol (HESP) was used to measure the prevalence of IEDU and its causes, comparing three pairs of periods: (1) March 2019 and 2020; (2) June 2019 and 2020; and (3) September 2019 and 2020. A bivariate analysis and multivariate logistic regression models, adjusted for confounding variables, were utilized. Results: In total, 822 emergency visits were included (137 per period). A total prevalence of IEDU of 14.1% was found. There was a significant decrease in IEDU in March 2020 (OR: 0.03), with a prevalence of 0.8%. No differences were found in the other periods. A mistrust in primary care was the leading cause of IEDU (65.1%). Conclusions: The impact of COVID-19 reduced the frequency of IEDU during the period of more significant population restrictions, with IEDU returning to previous levels in subsequent months. Targeted actions in the field of population education and an improvement in primary care are positioned as strategies that could mitigate its impact

    Caso Grúas Ruiz

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    Las estrategias competitivas son las posibles líneas de actuación de las que dispone la empresa para competir mejor en mercados determinados, con productos o servicios concretos, de tal forma que se genere una posición competitiva ventajosa para la misma. Aunque la empresa se proponga competir en un mercado provincial o regional, para tener éxito en un contexto global, tiene que combinar dos extremos aparentemente irreconciliables. Por un lado tendrá que «pegarse al terreno» para conocer y aportar valor a sus clientes, mientras que, por otro lado, tendrá que conocer y estar presente en las iniciativas de valor en todos los ámbitos. Desde el punto de vista de sus negocios, la empresa deberá plantear su estrategia competitiva de acuerdo con estas premisas.En este caso se describen las bases de la ventaja competitiva de una empresa, creada en la provincia de Jaén, que ha sabido mantener a lo largo del tiempo. El origen de los aspectos en los que se sustentan sus posibles ventajas competitivas, creemos que está en su carácter familiar. Cuenta con su propia forma de hacer las cosas, además de con una serie de conocimientos y habilidades basados en la experiencia de su fundador que se han sabido transmitir al incorporarse a la empresa la segunda generación

    Fabrication and deposition of copper and copper oxide nanoparticles by laser ablation in open air

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    The proximity of the “post-antibiotic era”, where infections and minor injuries could be a cause of death, there are urges to seek an alternative for the cure of infectious diseases. Copper nanoparticles and their huge potential as a bactericidal agent could be a solution. In this work, Cu and Cu oxide nanoparticles were synthesized by laser ablation in open air and in argon atmosphere using 532 and 1064 nm radiation generated by nanosecond and picosecond Nd:YVO4 lasers, respectively, to be directly deposited onto Ti substrates. Size, morphology, composition and the crystalline structure of the produced nanoparticles have been studied by the means of field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), the energy dispersive spectroscopy of X-rays (EDS), selected area electron diffraction (SAED) and X-ray diffraction (XRD). The UV-VIS absorbance of the thin layer of nanoparticles was also measured, and the antibacterial capacity of the obtained deposits tested against Staphylococcus aureus. The obtained deposits consisted of porous coatings composed of copper and copper oxide nanoparticles interconnected to form chain-like aggregates. The use of the argon atmosphere contributed to reduce significantly the formation of Cu oxide species. The synthesized and deposited nanoparticles exhibited an inhibitory effect upon S. aureus.Peer ReviewedPostprint (published version

    Children and Parental Barriers to Active Commuting to School: A Comparison Study

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    The main objectives of this study were: to compare the barriers to active commuting to and from school (ACS) between children and their parents separately for children and adolescents; and to analyze the association between ACS and the children’s and parents’ barriers. A total of 401 child–parent pairs, from Granada, Jaén, Toledo and Valencia, self-reported, separately, their mode of commuting to school and work, respectively, and the children’s barriers to ACS. T-tests and chi-square tests were used to analyze the differences by age for continuous and categorical variables, respectively. Binary logistic regressions were performed to study the association between ACS barriers of children and parents and ACS. Both children and adolescents perceived higher physical and motivational barriers and social support barriers towards ACS than their parents (all p < 0.05). Additionally, the parents perceived higher distance, traffic safety, convenience, built environment, crime-related safety and weather as barriers towards ACS, than their children (all p < 0.05). Moreover, a higher perception of barriers was related to lower ACS. The results of our study showed the necessity of attenuating the perceptions of children and their parents in order to increase ACS. This is relevant to develop interventions in the specific contexts of each barrier and involving both populations.Spanish Ministry of Economy, Industry and CompetitivenessEuropean Commission DEP2016-75598-RUniversity of Granada, Plan Propio de Investigacion 2016, Excellence actions: Units of ExcellenceUnit of Excellence on Exercise and Health (UCEES)Junta de AndalucíaEuropean CommissionEuropean Social Fund (ESF

    Importance of twitching and surface-associated motility in the virulence of Acinetobacter baumannii

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    Acinetobacter baumannii is a pathogen of increasing clinical importance worldwide, especially given its ability to readily acquire resistance determinants. Motile strains of this bacterium can move by either or both of two types of motility: (i) twitching, driven by type IV pili, and (ii) surface-associated motility, an appendage-independent form of movement. A. baumannii strain MAR002 possesses both twitching and surface-associated motility. In this study, we isolated spontaneous rifampin-resistant mutants of strain MAR002 in which point mutations in the rpoB gene were identified that resulted in an altered motility pattern. Transcriptomic analysis of mutants lacking twitching, surface-associated motility, or both led to the identification of deregulated genes within each motility phenotype, based on their level of expression and their biological function. Investigations of the corresponding knockout mutants revealed several genes involved in the motility of A. baumannii strain MAR002, including two involved in twitching (encoding a minor pilin subunit and an RND [resistance nodulation division] component), one in surface-associated motility (encoding an amino acid permease), and eight in both (encoding RND and ABC components, the energy transducer TonB, the porin OprD, the T6SS component TagF, an IclR transcriptional regulator, a PQQ-dependent sugar dehydrogenase, and a putative pectate lyase). Virulence assays showed the reduced pathogenicity of mutants with impairments in both types of motility or in surface-associated motility alone. By contrast, the virulence of twitching-affected mutants was not affected. These results shed light on the key role of surface-associated motility and the limited role of twitching in the pathogenicity of A. baumannii

    Novel insights and mechanisms of diet-induced obesity: Mid-term versus long-term effects on hepatic transcriptome and antioxidant capacity in Sprague-Dawley rats

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    Supplementary data to this article can be found online at https://doi.org/10.1016/j.lfs.2023.121746Aims The study of molecular mechanisms related to obesity and associated pathologies like type 2-diabetes and non-alcoholic fatty liver disease requires animal experimental models in which the type of obesogenic diet and length of the experimental period to induce obesity deeply affect the metabolic alterations. Therefore, this study aimed to test the influence of aging along a rat model of diet-induced obesity in gene expression of the hepatic transcriptome. Main methods A high-fat/high-fructose diet to induce obesity was used. Mid- (13 weeks) and long-term (21 weeks) periods were established. Caloric intake, bodyweight, hepatic fat, fatty acid profile, histological changes, antioxidant activity, and complete transcriptome were analyzed. Key findings Excess bodyweight, hepatic steatosis and altered lipid histology, modifications in liver antioxidant activity, and dysregulated expression of transcripts related to cell structure, glucose & lipid metabolism, antioxidant & detoxifying capacity were found. Modifications in obese and control rats were accounted for by the different lengths of the experimental period studied. Significance Main mechanisms of hepatic fat accumulation were de novo lipogenesis or altered fatty acid catabolism for mid- or long-term study, respectively. Therefore, the choice of obesity-induction length is a key factor in the model of obesity used as a control for each specific experimental design.Spanish Ministry of Science and Innovation, and the European Union through projects B-AGR-662-UGR20, RTI-2018-100934-B-I00, and the FEDER program, respectivel

    Una dieta alta en proteína produce estrés oxidativo en el cerebro de ratas: acción protectora del ejercicio de alta intensidad sobre peroxidación lipídica

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    diets as well as aerobic exercise could promote antioxidant capacity and consequently reduce free radicals overproduction on brain. However, little is know regarding to the high-protein diets and high intensity exercise on oxidative stress production. The aim of this study was to analyse the effects of high-protein diets and high-intensity exercise (HIE) on brain oxidative stress markers. Materials and Methods: A total of 40 male Wistar rats were randomly distributed in 4 experimental groups (n=10): normal-protein or high-protein diets with or without HIE for an experimental period of 12 weeks. Main oxidative damage markers in brain such as thiobarbituric acid-reactive substances (TBARs) and protein carbonyl content (PCC) were assessed. In addition, brain manganese superoxide dismutase (Mn-SOD), cooper/ zinc superoxide dismutase (CuZn-SOD) and catalase (CAT) antioxidant enzymes activity, and protein level of Nuclear factor erythroid 2 related factor 2 (Nrf2) were measured. Results and discussion: Brain TBARs, PCC, tSOD, Mn-SOD, CuZn-SOD and CAT levels were higher in the high-protein compared to the normal-protein groups (all, p<0.05). In addition, the expression of Nrf2 protein was higher in the high-protein and HIE groups compared to the normal-protein and sedentary groups, respectively (both, p<0.01). A protein amount*HIE interaction was found on brain TBARs content, and tSOD and CuZn- SOD activity derived from a HIE-induced decrease in the high-protein but not in the normal-protein group (p<0.05). Conclusions: The high-protein diets consumption produce higher levels of brain lipid peroxidation, in spite of higher levels of antioxidant enzymatic capacity. However, HIE may attenuate the deleterious effect of a high-protein diet on brain lipid peroxidation when both effects are combined.Introducción: Es conocido que la proteína de soja así como la práctica de ejercicio físico aeróbico pueden incrementar la capacidad antioxidante y con ello reducir la sobreproducción de radicales libres en el cerebro. Sin embargo, existe desconocimiento sobre el efecto del consumo de dietas hiperproteicas y el entrenamiento de alta intensidad (EAI) sobre dicho estrés oxidativo. El objetivo del presente estudio fue analizar la influencia del consumo de una dieta hiperproteica y de EAI sobre marcadores de estrés oxidativo en cerebro. Métodos: Cuarenta ratas Wistar macho adultas fueron aleatoriamente distribuidas en 4 grupos experimentales (n=10): dieta normoproteica o hiperproteica, con o sin EAI durante un periodo experimental de 12 semanas. Se determinaron los principales marcadores de daño oxidativo en cerebro como sustancias reactivas del ácido tiobarbitúrico (TBARs) y el contenido de grupos carbonilos (PCC). Además, se midieron las actividades enzimáticas superóxido dismutasa del manganeso (Mn-SOD), de cobre/ zinc (CuZn-SOD) y catalasa (CAT), así como el nivel de proteína del factor nuclear eritroide-2 (Nrf2). Resultados: Los niveles de TBARs, PCC, tSOD, Mn- SOD, CuZn-SOD y CAT fueron significativamente mayores en los grupos hiperproteicos en comparación con los normoproteicos (todas, p<0,05). La expresión de la proteína Nrf2 fue mayor en los grupos hiperproteicos y con EAI en comparación con los grupos normorpoteicos y sedentarios, respectivamente (ambos, p<0,01). Se observó una interacción en la disminución de los niveles de TBARs, tSOD y CuZn-SOD producida por el EAI en el grupo hiperproteico que no fue reflejada en el grupo normoproteico (p=0,05). Conclusión: El consumo de una dieta hiperproteica produce altos niveles de peroxidación lipídica en el cerebro, a pesar de los altos niveles de capacidad enzimática antioxidante detectados. Sin embargo, el efecto del EAI podría atenuar los niveles de peroxidación lipídica producidos por el consumo de una dieta hiperproteica.This study was supported by the project DEP2008-04376 from the Ministry of Science and Innovation and grants from the Spanish Ministry of Education (D.C.M. grant number AP2009-3173), (E.N. grant number AP2009-5033)
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