Búsqueda de posibles variantes funcionales del gen ABCA1 en individuos mexicanos con hipo e hiperα-lipoproteinemia y su asociación con otros rasgos metabólicos

Aunque la proteína ABCA1 (por sus siglas en inglés ATP-binding cassette transporter A1) es conocida por su función en el eflujo de colesterol y la formación de lipoproteínas de alta densidad (HDL), se expresa en una gran variedad de tejidos donde podría tener diferentes funciones. Puesto que la hipoα-lipoproteinemia (niveles sérico bajos de HDL) tiene una alta prevalencia en México, se analizó la secuencia del gen ABCA1 en individuos mestizos mexicanos con los niveles más altos y más bajos de HDL de la población, con el fin de identificar variantes funcionales. Se encontró una variante no sinónima (R230C) que fue muy frecuente en los individuos con niveles bajos de HDL, pero no en aquéllos con niveles altos de HDL (P=0.00006). Por este motivo se analizó la frecuencia de esta variante en mestizos mexicanos de la población general de la Ciudad de México, buscando posibles asociaciones con otros rasgos metabólicos. Se identificaron los genotipos R230C en 429 mestizos mexicanos utilizando sondas Taqman, encontrándose la variante en el 20.1% de ellos, con una frecuencia alélica de 10.9%. La variante R230C mostró asociación estadísticamente significativa no sólo con niveles séricos bajos de HDL-colesterol y apolipoproteína A-I, sino también con obesidad (RM=2.527, P=0.005), síndrome metabólico (RM=1.893, P= 0.0007) y diabetes mellitus tipo 2 (RM=4.527, P=0.003). Estas asociaciones no perdieron su significancia aún después de ajustar por mezcla étnica (P=0.011, P=0.001 y P=0.006, respectivamente). La variante R230C había sido previamente descrita como una mutación en un indígena canadiense Oji-Cree con hipoα-lipoproteinemia y no ha sido encontrada en las poblaciones caucásica, africana o asiática. Por este motivo se buscó esta variante en 37 individuos yaquis, 67 teneek, 35 purépechas y 40 mayas, encontrándose frecuencias alélicas significativamente más altas que en la población mestiza mexicana (17.9 a 28.8%; p < 0.01). Éste es el primer estudio que reporta la asociación de una variante del gen ABCA1 con obesidad y sus comorbilidades, la cual parece tener un carácter ancestral y es epidemiológicamente relevante en la población mexicana.Although the ATP-binding cassette transporter A1 (ABCA1) is well known for its role in cholesterol efflux and HDL formation, it is expressed in various tissues where it may have different functions. Because hypoα-lipoproteinemia is highly prevalent in Mexico, we screened the ABCA1 coding sequence in Mexican individuals with low and high HDL cholesterol levels to seek functional variants. A highly frequent nonsynonymous variant (R230C) was identified in low–HDL cholesterol but not in high–HDL cholesterol individuals (P=0.00006). We thus assessed its frequency in the Mexican-Mestizo general population, seeking possible associations with several metabolic traits. R230C was screened in 429 Mexican Mestizos using Taqman assays, and it was found in 20.1% of these individuals. The variant was significantly associated not only with decreased HDL-cholesterol and apolipoprotein A-I levels but also with obesity (OR=2.527, P=0.005), the metabolic syndrome (OR=1.893, P= 0.0007), and type 2 diabetes (OR=4.527, P=0.003). All of these associations remained significant after adjusting for admixture (P=0.011, P=0.001, and P=0.006, respectively). The R230C variant was previously described as a mutation in an Oji-Cree individual with hypoα-lipoproteinemia and has not been found in Caucasian, African or Asian populations. For this reason this variant was genotyped in 37 Yaqui, 67 Teneek, 35 Purepecha and 40 Mayan individuals, who showed significantly higher allele frequencies (17.9 to 28.8%) as compared to Mexican mestizos (10.9%; p < 0.01). This is the first study reporting the association of an ABCA1 variant with obesity and obesity-related comorbidities, which seems to be an ancestral marker and is epidemiologically relevant in the Mexican population

Design Aspects of a Broadband Beam-Reconfigurable Leaky-Wave Antenna

Design aspects of a novel beam-reconfigurable pla-nar series-fed array are addressed to achieve beam steering with frequency tunability over a relatively broad bandwidth. The design is possible thanks to the use of the complementary strip-slot, which is an innovative broadly matched microstrip radiator, and the careful selection of the phase shifter parameters.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Redes de empresas : proposta de uma tipologia para classificação aplicada na indústria de cerâmica de revestimento

Este artigo se insere no contexto da atualização da temática das redes de empresas presente na Academia nestes tempos. Seu objetivo é propor uma tipologia para a classificação das redes de empresas. Esta tipologia deriva da literatura consultada e dos casos estudados, vinculando-a a quatro indicadores: direcionalidade, localização, formalização e poder. Para a ilustração da aplicação desta tipologia foram consideradas três redes dentro da indústria de cerâmica de revestimento, duas no Brasil e uma na Espanha. A partir dos dados levantados com distintos instrumentos, como questionários, entrevistas não dirigidas e pesquisa bibliográfica, pôde-se aplicar a tipologia e inferir sobre a especificidade de cada rede e seu grau de aproximação com aquela considerada mais ajustada à tipologia proposta. Este exercício mostrou as diferenças entre essas redes, como, por exemplo, o fato de em uma mesma indústria, e até dentro de um mesmo país, as redes podem ser estruturas singulares e similares ao mesmo tempo. Mostrou também que, utilizando uma rede como referência, pode-se analisar a aproximação de outras redes de empresas a essa referência. A proposta ampliou a leitura de classificação que vinha sendo aplicada para além dos eixos de direcionalidade e formalização. _________________________________________________________________________________ ABSTRACTThis article searches a contribution to actualize on firms networking theme existing on Academy nowadays. Its objective is to propose a classification typology to firm network. This typology comes from bibliographical research and from three clusters studied of ceramic tile industry, two on Brazil and one in Spain. The proposition links the clusters to four indicators: directionality; localization; formalization and power. Methodological proceedings were survey to CEOs; and supporting institutions; and bibliographical research. Results have shown each network specificity and its distance to more appropriate cluster according to typology. This work showed differences among networks such, in the same industry and country, two networks can be similar and singular at the same time. Also, using a network as reference, it was possible analyzing other networks to this one according to its characteristics. This proposition makes a contribution to network classification beyond directionality and formalization axis

Consideraciones sobre el amplificador distribuido como amplificador de potencia

In this contribution, a short review of independent research activities on distributed power amplification is presented. An analysis of the intrinsic limitations of distributed power amplifiers serves as a guideline to present some solutions available in the literature. This analysis shows that a distributed amplifier can work as an optimum class-A power combiner for a discrete set of frequency values determined by the selected active devices, and the phase shift and characteristic impedances between stages. The solutions proposed over the years present several circuital configurations that offer different options for the distribution of the available gain-bandwidth product, which are briefly reviewed in this contribution.Este trabajo ha sido financiado por el Ministerio de Ciencia e Innovación (Programa Consolider-Ingenio 2010) en el marco del proyecto CSD2008-00066 (’EMET’-Engineering Metamaterials) y por la Junta de Andalucía por medio del proyecto P10-TIC-6883

Disentangling epitaxial growth mechanisms of solution derived functional oxide thin films

This study investigates the mechanisms of epitaxial development and functional properties of oxide thin films (Ce0.9Zr0.1O2−y, LaNiO3, and Ba0.8Sr0.2TiO3) grown on single crystal substrates (Y2O3:ZrO2, LaAlO3, and SrTiO3) by the chemical solution deposition approach. Rapid thermal annealing furnaces are very powerful tools in this study providing valuable information of the early stages of nucleation, the kinetics of epitaxial film growth, and the coarsening of nanocrystalline phases. Advanced transmission electron microscopies, X-ray diffraction, and atomic force microscopy are employed to investigate the film microstructure and morphology, microstrain relaxation, and epitaxial crystallization. This study demonstrates that the isothermal evolution toward epitaxial film growth follows a self-limited process driven by atomic diffusion, and surface and interface energy minimization. All investigated oxides experience a transformation from the polycrystalline to the epitaxial phase. This study unequivocally evidences that the film thickness highly influences the epitaxial crystallization rate due to the competition between heterogeneous and homogeneous nucleation barriers and the fast coarsening of polycrystalline grains as compared to epitaxial growth. The investigated films possess good functional properties, and this study successfully confirms an improvement at long annealing times that can be correlated with grain boundary healing processes. Thick epitaxial films can be crystallized by growing sequential individual epitaxial layers.We acknowledge financial support from Spanish Ministry of Economy and Competitiveness through the “Severo Ochoa” Programme for Centres of Excellence in R&D (SEV-2015-0496), CONSOLIDER Excellence Network (MAT2015-68994-REDC), COACHSUPENERGY project (MAT2014-56063-C2-1-R, co-financed by the European Regional Development Fund), and the projects MAT2011-28874-C02-01, ENE2014-56109-C3-3-R and Consolider Nanoselect (CSD2007-00041), and from the Catalan Government (2014-SGR-753 and Xarmae). AQ and MdlM are also grateful for JAE-Predoc fellowship from CSIC (E-08-2012-1321248 and E-08-2013-1028356, co-financed by the European Social Fund).Peer Reviewe

Mapping SMEs financial literacy research: bibliometric analysis and literature review

Financial literacy in SMEs constitutes an emerging research field, increasing its scientific production exponentially in recent years, and in a very heterogeneous way. The purpose of this paper its to review 88 contributions for the period 2005-2020 through bibliometric techniques. Specifically, we carry out a co-occurrence and co-citation analysis of the keywords and cited references to obtain two thematic clusters and four theoretical roots. Thus, through its combination in five thematic groups, we develop an integrative framework that allow us to identify the research paths addressed, and propose important lines of future research, providing a research guide for scholars.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Financial literacy in SMES: a bibliometric analysis of an emerging topic

The purpose of this study is to review the existing literature on financial literacy (FL) in SMEs in general, and particularly in family SMEs, and describe the current state of publications in this area through the use of bibliometric techniques. The review of 88 documents, in the period between 2005 and 2020, will identify the agents involved (countries, organizations, journals, authors, publications) that have the greatest influence on the development of this research topic. In turn, the content analysis through the co-occurrence of the author's keywords will detect the driving themes. In the first analysis carried out, it is evident the positive impact that FL has on the performance and access to financing of the SMEs. Other lines of growing interest and still little developed are the effect of FL on firm capital structure and innovation. The main contribution of this research is to provide coverage to the existing gap in FL in SMEs bibliometric analysis, helping scholars to locate the existing gaps in this research topic.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

DC-18 GHz MMIC tapered distributed power amplifier

A DC-18 GHz MMIC tapered power distributed amplifier has been designed and simulated in GaAs technology. The amplifier has been designed according to the theory for power and efficiency maximization based on tapered drain lines. Small- and large-signal simulations have been carried out to evaluate the amplifier’s behaviour. Results suggest that it is possible to achieve a good performance in terms of output power and efficiency for a wide bandwidth.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Huge recurrent gastric neuroendocrine tumor: a second-line chemotherapeutic dilemma

Chemotherapy is considered “state of the art” for the treatment of poorly differentiated neuroendocrine neoplasms. Unfortunately, there is no standard effective post-first-line treatment for relapsing high-grade gastroenteropancreatic neuroendocrine neoplasms. We report the case of a patient with a gastric neuroendocrine carcinoma stage IV, with massive gastrointestinal bleeding at diagnosis. After the first line of platin-based chemotherapy a major tumoral response was documented, but the patient relapsed after 4 months. A second line of chemotherapy treatment was given, with the FOLFOX regimen, and the patient has been free of progression for almost 2 years. There is no second-line standard treatment accepted for this type of carcinoma, but 5-fluorouracil combined with oxaliplatin showed interesting antitumor activity