Derivados del Nylon 3 con grupos laterales alcoxicarbonilos ramificados y cíclicos

El presente trabajo se ha centrado en la síntesis, caracterización y estudio estructural de poli(alfa-alquil-beta-L-aspartato)s con grupos laterales ramificados y cíclicos. Se han sintetizado los monómero: (S)-4-alcoxicarbonil-2-azetidinonas cuya síntesis se basa en la transesterificación de la beta-lactama del éster bencílico del ácido L-aspártico con el correspondiente alcohol. Se han establecido las condiciones óptimas de la polimerización aniónica por apertura del anillo de lactama, haciendo especial énfasis en el papel que ejerce la polaridad del solvente. En concreto el estudio se ha efectuado sobre la obtención del poli(alfa-isobutil-beta-L-aspartato). Se ha investigado la influencia de las condiciones de polimerización sobre la microestructura de los poli(alfa-isobutil-beta-D,L-aspartato)s obtenidos a partir de mezclas de monómeros enantiómeros. Se ha estudiado la conformación en disolución y la estructura cristalina en estado sólido, mediante difracción de rayos X, de los estereocopolímeros en relación con los polímeros ópticamente puros. Se han sintetizado una serie de poli(alfa-alquil-beta-L-aspartato)s nuevos con grupos alquilo ramificados y cíclicos, según las condiciones óptimas de polimerización establecidas para el derivado isobutílico. Se ha efectuado el análisis térmico de todos los polímeros y el estudio de la conformación en disolución por resonancia magnética nuclear y por dicroismo circular, detectando las transiciones de conformación. Mediante la técnica de difracción de rayos X se ha analizado el comportamiento estructural de la familia de poli(alfa-alquil-beta-L-aspartato)s sintetizada, estableciendo la comparación con los miembros de esta familia con grupos laterales lineales. Se ha llevado a cabo el análisis térmico dinamomecánico de los poli(alfa-alquil-beta-L-aspartato)s mediante la técnica de DMTA. Se han determinado las transiciones características para cada miembro y se ha establecido la correlación entre la relajación estructural de los polímeros y la constitución de la unidad repetitiva. Por último, se ha realizado el estudio de la degradación por ultrasonidos de los poli(-alquil--L-aspartato)s y de ciertos poliglutamatos, de forma que se han establecido las características generales de la degradación, así como la influencia que puede ejercer la estructura de la cadena principal y lateral sobre los resultados de dicha degradación

Hydrophobic modification of poly(gamma-glutamic acid) by grafting 4-phenyl-butyl side groups for the encapsulation and release of doxorubicin

The delivery of drugs is a great challenge, since most of active pharmaceutical ingredients developed today are hydrophobic and poorly water soluble. From this perspective, drug encapsulation on biodegradable and biocompatible polymers can surpass this problem. Poly(gamma-glutamic acid) (PGGA), a bioedible and biocompatible polymer has been chosen for this purpose. Carboxylic side groups of PGGA have been partially esterified with 4-phenyl-butyl bromide, producing a series of aliphatic–aromatic ester derivatives with different hydrophilic–lipophilic balances. Using nanoprecipitation or emulsion/evaporation methods, these copolymers were self-assembled in a water solution, forming nanoparticles with average diameters between 89 and 374 nm and zeta potential values between -13.1 and -49.5 mV. The hydrophobic core containing 4-phenyl-butyl side groups was used for the encapsulation of an anticancer drug, such as Doxorubicin (DOX). The highest encapsulation efficiency was reached for a copolymer derived from PGGA, with a 46 mol % degree of esterification. Drug release studies carried out for 5 days at different pHs (4.2 and 7.4) indicated that DOX was released faster at pH 4.2, revealing the potential of these nanoparticles as chemotherapy agents.Peer ReviewedPostprint (published version

Nanoparticles made of poly(gama-glutamic acid) derivatives for drug delivery systems

One of the treatments for cancer is chemotherapy but most anticancer drugs have a low therapeutic index, which causes toxicity complications in the healthy tissues [1]. To minimize these complications and improve the effect of the existing drugs, drug delivery by nanoparticles have drawn more attention as they are easy to produce and can also be prepared through biocompatible polymers [2]. Here, we report the preparation of polymer nanoparticles derived from esters of poly(¿-glutamic acid) which could be able to encapsulate hydrophobic drugs that can be used as drug delivery systems (DDS) for the treatment of different tumours. In this work, PGGA has been modified in order to improve its solubility in organic solvents and its processing capacity of this water-soluble polymer. Due to the fact that most of the anticancer drugs are lipophilic, the hydrophobic modification of PGGA will enhance the drug encapsulation.Postprint (published version

Metodología de reingeniería del software para la remodelación de aplicaciones científicas heredadas

La reingeniería de sistemas heredados tiene por finalidad reestructurar o transformar viejossistemas en aplicaciones más fáciles de mantener, con entornos más agradables e integradas ennuevas plataformas de hardware/software. Tratamos de dar una visión general de lo que es lareingeniería de software y cuáles son las actitudes que se pueden tomar a la hora de modernizarun sistema legado que se ha quedado obsoleto en cuanto a operatividad, aspecto y software debase sobre el que se ejecuta, pero de probada eficiencia y que mantiene su funcionalidad.Mostramos las características de un proceso de desarrollo que se adapta a este tipo deaplicaciones, verificado, mediante el caso de estudio, la transformación de una aplicación escritaen un lenguaje imperativo, no estructurado, a un nuevo lenguaje visual y orientado a objetos,describiendo las diversas fases de la metodología aplicadas a un caso concreto.Legacy Systems Reengineering has as primary goal to restructure and transform old systems ineasier to maintain applications with nicer and more integrated environments that they run innew platforms of hardware/software. We try to give a general view of what is the softwarereengineering and which are the approaches that can be taken when modernizing a legacysystem that has been obsolete as for operability, but of proved efficiency and that maintains itsfunctionality. We show the characteristics of a development process that adapts itself to thistype of systems, verified by means of the case of study, the transformation of an applicationwritten in an imperative language, no structured, to a new visual and object oriented language,describing the different stages of the methodology applied to a particular case

Family functioning and quality of life among families in eating disorders: a comparison with substance-related disorders and healthy controls

This is the peer reviewed version of the following article: European Eating Disorders Review 24.4 (2016): 294-303, which has been published in final form at https://doi.org/10.1002/erv.2440. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingThe aim of this study was to compare the family functioning of Spanish parents of patients with an eating disorder (ED) with that of carers of patients with substance-related disorders (SRDs) and families of healthy controls (HC). This cross-sectional study included 48 mothers and 45 fathers of 48 adolescent patients with an ED, 47 mothers and 37 fathers of 47 patients with an SRD and 66 mothers and 50 fathers of 68 HCs. Families of ED patients reported lower levels of criticism, symptom accommodation and negative caregiving experience than families of SRD patients. However, relatives of both ED and SRD patients reported similar levels of quality of life related to their mental health. Furthermore, families of HCs generally exhibited better scores on all scales assessing their caregiving experiences. Regarding gender differences, there was a tendency in mothers, primarily those from the ED group, to report more adverse experiences as caregivers compared with fathers. Symptoms characteristic to each disorder may be associated with differential patterns of family functioning and may require specifically tailored family interventions. Early family intervention in adolescence is crucial, as relatives' quality of life does not seem to have been badly affected at this point in the course of the illnessDr Sepulveda has a post-doctoral Ramon and Cajal scholarship from the Spanish Ministry of Science and Innovation (RYC-2009-05092) as well as a project funding from the same Ministry (PSI2011-23127). Dr Anastasiadou was awarded with a Research Fellowship for students of PhD Programmes distinguished with Mention of Excellenc

Compounds with epoxy resins and phase change materials for storage in solar applications

Composite materials have great potential for growth due to their excellent properties and their multiple applications. The study of the thermal properties of the new composites resulting from the combination of epoxy resin and phase change materials (PCM), as well as thickening agents and thermally conductive compounds, was the objective of this work. For this purpose, different samples were manufactured by combining epoxy resins, organic PCMs (paraffins), and aluminum particles. Several properties were analyzed: thermal behavior (by differential scanning calorimetry technique), hardness, etc. To carry out this analysis, parameters of PCM quantity and metallic particles in the composition were varied. The results showed that the epoxy resin acted as a matrix containing the rest of the components and encapsulating the PCM. The organic PCM showed reversibility when subjected to multiple cycles. The enthalpy of the organic PCM–resin compound varied linearly according to the PCM content in the sample. For the content of this material in the samples to reach up to 40%, the use of thickening agents was necessary. The use of metallic particles improved the conductivity of the composites even while maintaining a low percentage by weight of metallic particles. Thermal simulations of the composite in bottom-coating a photovoltaic panel estimated a reduction of several degrees Celsius, showing the potential use of the PCM–epoxy resin for improving the energy production of such panels.Departmen of Culture and Education of the Regional Government of Castilla y León, Spain (ORDEN EDU/667/2019 de 5 de Julio

Spanish photovoltaic solar energy: institutional change, financial effects, and the business sector

Spain is a country with a high dependence on fossil fuels. For this reason, in 2007, it implemented a bonus system that aimed to encourage the production of renewable energies, particularly photovoltaic solar energy. These production bonuses, guaranteed by the Spanish government, led to an exponential increase in the number of companies in the market and, consequently, the MWh produced. However, in 2012, given the excessive budgetary burden involved in maintaining this “feed-in tariff” system and after several years of institutional instability, the aforementioned system of incentives for phoyovoltaic (PV) energy was eliminated. This paper has tried to analyze the consequences of this institutional change, a clear example of the “hold up” problem. For this purpose, a sample of 5354 companies, which was divided, geographically, into Spanish regions and, temporarily, into three different periods, has been taken, considering diverse economic and financial variables. The results show a notable weakening of the sector that, due to the effects of the regulatory change, has lost attractiveness and profitability for investors and is consequently suffering from stagnation, which has led to the disappearance of many companies in the sector.Raquel Fernández González gratefully acknowledge the financial support provided by the Xunta de Galicia under Grants ED431C2018/48 and ED431E2018/07 and the Ministry of Economy and Competitiveness under Grant RTI2018-099225-B-100. This research was funded by Regional Government of Castilla y León under the “Support Program for Recognized Research Groups of Public Universities of Castilla y León” (ORDEN EDU/667/2019) and the Spanish Ministry of Science, Innovation & Universities under the I + D + i state program “Challenges Research Projects” (Ref. RTI2018-098900-B-I00)

Modification of microbial polymers by thiol-ene click reaction: Nanoparticle formation and drug encapsulation

Comb-like amphiphilic polymers were obtained by grafting long paraffinic chains on microbial poly(¿,dl-glutamic acid) and poly(ß,l-malic acid) through two steps, i.e. allylation of the carboxylic side groups followed by UV-initiated thiol-ene click reaction with 1-alkanethiols bearing 8, 12 and 16 carbon atoms, and their characterization was accomplished by 1H NMR, GPC and DSC. The grafted polymers were capable of self-assembling in nanoparticles with diameters in the 80–240 nm range. Incubation in water under physiological conditions led to hydrolysis of the lateral ester bonds followed by scission of the polyamide or polyester main chain. The model drugs, Theophylline and Carbamazepine, were efficiently encapsulated in these systems with much better results attained for the later. Drug release from nanoparticles incubated under physiological conditions occurred with a burst effect and were completely discharged in 24 h. Release profiles recorded from drug-loaded films suggested that the drug was delivered in both cases through a diffusion process.Peer ReviewedPostprint (author's final draft

Deletion of miRNA processing enzyme Dicer in POMC-expressing cells leads to pituitary dysfunction, neurodegeneration and development of obesity

MicroRNAs (miRNAs) have recently emerged as key regulators of metabolism. However, their potential role in the central regulation of whole-body energy homeostasis is still unknown. In this study we show that the expression of Dicer, an essential endoribonuclease for miRNA maturation, is modulated by nutrient availability and excess in the hypothalamus. Conditional deletion of Dicer in POMC-expressing cells resulted in obesity, characterized by hyperphagia, increased adiposity, hyperleptinemia, defective glucose metabolism and alterations in the pituitary-adrenal axis. The development of the obese phenotype was paralleled by a POMC neuron degenerative process that started around 3 weeks of age. Hypothalamic transcriptomic analysis in presymptomatic POMCDicerKO mice revealed the downregulation of genes implicated in biological pathways associated with classical neurodegenerative disorders, such as MAPK signaling, ubiquitin-proteosome system, autophagy and ribosome biosynthesis. Collectively, our results highlight a key role for miRNAs in POMC neuron survival and the consequent development of neurodegenerative obesity

Proteins isolated from Ganxet common bean (Phaseolus vulgaris L.) landrace: techno-functional and antioxidant properties

Ganxetprotein isolates (GPI) were assessed for antioxidant and functional properties including emulsifyingand foaming capacity. The protein content and water activity (aw) value of GPI were 91.08 4.15% and0.248 0.008%, respectively. The oil- and water-holding capacities of GPI were calculated as 2.76 0.33and 1.25 0.11 g g 1of GPI, respectively (P<0.05). Foaming and emulsifying properties were found to bepH-dependent (P<0.05)This work was supported by the CERCA ProgrammeofGeneralitat de Catalunya. Tom as Lafarga andIngrid Aguil o-Aguayo thank the Spanish Ministry ofEconomy, Industry and Competitiveness and theEuropean Social Fund for theJuan de la Cierva(IJC2018-035287-I) and Postdoctoral Senior GrantRamon y Cajal(RYC-2016-19949), respectivelyPostprint (published version