Manufacturing and characterization of poly(lactic acid) composites with hydroxyapatite

This is the peer reviewed version of the following article: Ferri, J.M., Jordà Sempere, José Jorge, Montanes, N. , Fenollar, Octavio, Balart, Rafael. (2017). Manufacturing and characterization of poly(lactic acid) composites with hydroxyapatite.Journal of Applied Polymer Science, 0. DOI: 10.1177/0892705717729014 , which has been published in final form at http://doi.org/10.1177/0892705717729014. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] Hydroxyapatite (HA), a naturally occurring calcium orthophosphate, possesses the most similar chemical composition to human bone. In this research work, composite materials were prepared using poly(lactic acid) (PLA) as a polymer matrix and HA as an osteoconductive filler for potential use in medical applications. Composites with varying HA content comprised in the 10¿30 wt% range were obtained by extrusion-compounding followed by injection molding. The effect of the HA loading on overall properties was assessed by mechanical characterization using tensile, flexural, impact, and hardness standard tests. Main thermal transitions of PLA-HA composites were obtained by differential scanning calorimetry (DSC) and degradation/decomposition at high temperatures was followed by thermogravimetric analysis. Dynamical behavior was assessed by dynamic mechanical thermal analysis and the dimensional stability was studied by thermomechanical analysis (TMA). As per the results, PLA-HA composites with 20¿30 wt% HA offer the best-balanced properties with a remarkable increase in the Young¿s modulus. The glass transition temperature remained almost constant with slight changes of less than 1C as measured by both DSC and TMA. TMA also revealed a remarkable decrease in the coefficient of linear thermal expansion. The overall results confirm the usefulness of these materials from a mechanical point of view for biomedical applications as they are characterized by high stiffness, tensile strength, and dimensional stability.The authors want to acknowledge the Ministry of Economy and Competitiveness (MINECO) for their financial support through the grant number MAT2014-59242- C2-1-R.Ferri, J.; Jordà Sempere, JJ.; Montanes, N.; Fenollar, O.; Balart, R. (2017). Manufacturing and characterization of poly(lactic acid) composites with hydroxyapatite. Journal of Applied Polymer Science. https://doi.org/10.1177/0892705717729014

Two-Sided Derivatives for Regular Expressions and for Hairpin Expressions

The aim of this paper is to design the polynomial construction of a finite recognizer for hairpin completions of regular languages. This is achieved by considering completions as new expression operators and by applying derivation techniques to the associated extended expressions called hairpin expressions. More precisely, we extend partial derivation of regular expressions to two-sided partial derivation of hairpin expressions and we show how to deduce a recognizer for a hairpin expression from its two-sided derived term automaton, providing an alternative proof of the fact that hairpin completions of regular languages are linear context-free.Comment: 28 page

Effect of Epoxidized and Maleinized Corn Oil on Properties of Polylactic Acid (PLA) and Polyhydroxybutyrate (PHB) Blend

[EN] The present work analyzes the influence of modified, epoxidized and maleinized corn oil as a plasticizing and/or compatibilizing agent in the PLA¿PHB blend (75% PLA and 25% PHB wt.%). The chemical modification processes of corn oil were successfully carried out and different quantities were used, between 0 and 10% wt.%. The different blends obtained were characterized by thermal, mechanical, morphological, and disintegration tests under composting conditions. It was observed that to achieve the same plasticizing effect, less maleinized corn oil (MCO) is needed than epoxidized corn oil (ECO). Both oils improve the ductile properties of the PLA¿PHB blend, such as elongation at break and impact absorb energy, however, the strength properties decrease. The ones that show the highest ductility values are those that contain 10% ECO and 5% MCO, improving the elongation of the break of the PLA¿PHB blend by more than 400% and by more than 800% for the sample PLA.This work was supported by the Spanish Ministry of Science and Innovation, NANOCIRCOIL (PID2021-123753NA-C33)Sempere-Torregrosa, J.; Ferri, J.; Rosa-Ramírez, HDL.; Pavón-Vargas, CP.; Samper, M. (2022). Effect of Epoxidized and Maleinized Corn Oil on Properties of Polylactic Acid (PLA) and Polyhydroxybutyrate (PHB) Blend. Polymers. 14(19):1-16. https://doi.org/10.3390/polym14194205116141

Activation of microglia in specific hypothalamic nuclei and the cerebellum of adult rats exposed to neonatal overnutrition

Much attention has been drawn to the possible involvement of hypothalamic inflammation in the pathogenesis of metabolic disorders, especially in response to a high-fat diet. Microglia, the macrophages of the central nervous system, can be activated by proinflammatory signals resulting in the local production of specific interleukins and cytokines, which in turn could exacerbate the pathogenic process. Because obesity itself is considered to be a state of chronic inflammation, we evaluated whether being overweight results in microglial activation in the hypothalamus of rats on a normal diet. Accordingly, we used a model of neonatal overnutrition that entailed adjustment of litter size at birth (small litters: four pups/dam versus normal litters: 12 pups/dam) and resulted in a 15% increase in bodyweight and increased circulating leptin levels at postnatal day 60. Rats that were overnourished during neonatal life had an increased number of activated microglia in specific hypothalamic areas such as the ventromedial hypothalamus, which is an important site for metabolic control. However, this effect was not confined to the hypothalamus because significant microglial activation was also observed in the cerebellar white matter. There was no change in circulating tumour necrosis factor (TNF) α levels or TNFα mRNA levels in either the hypothalamus or cerebellum. Interleukin (IL)6 protein levels were higher in both the hypothalamus and cerebellum, with no change in IL6 mRNA levels. Because circulating IL6 levels were elevated, this rise in central IL6 could be a result of increased uptake. Thus, activation of microglia occurs in adult rats exposed to neonatal overnutrition and a moderate increase in weight gain on a normal diet, possibly representing a secondary response to systemic inflammation. Moreover, this activation could result in local changes in specific hypothalamic nuclei that in turn further deregulate metabolic homeostasi

Review of the effects of protection in marine protected areas: current knowledge and gaps

The effectiveness of marine protected areas (MPAs) and the conservation of marine environments must be based on reliable information on the quality of the marine environment that can be obtained in a reasonable timeframe. We reviewed studies that evaluated all aspects related to the effectiveness of MPAs in order to describe how the studies were conducted and to detect fields in which research is lacking. Existing parameters used to evaluate the effectiveness of MPAs are summarised. Two–hundred and twenty–two publications were reviewed. We identified the most commonly used study subjects and methodological approaches. Most of the studies concentrated on biological parameters. Peer reviewed studies were based on control vs. impact design. BACI and mBACI designs were used in very few studies. Through this review, we have identified gaps in the objectives assigned to MPAs and the way in which they have been evaluated. We suggest some guidelines aimed at improving the assessment of the effects of protection in MPAsRevisión de los efectos de la protección en las áreas marinas protegidas: conocimiento y deficiencias actuales.— La efectividad de las áreas marinas protegidas (AMPs) y la conservación del medio ambiente marino debe basarse en información fiable sobre la calidad del medio marino que pueda obtenerse en un plazo de tiempo razonable. Se revisaron estudios que evalúan aspectos relacionados con la efectividad de las AMPs con el fin de describir cómo se realizaron los estudios y detectar donde existen vacíos en la investigación. En este estudio se enumeran los parámetros existentes para evaluar la efectividad de las AMPs. Se revisaron 224 publicaciones. Identificamos los objetos de estudio más utilizados y los enfoques metodológicos. La mayoría de los estudios se centran en el estudio de parámetros biológicos. Los estudios publicados se basaron en el diseño control frente a impacto. En muy pocos estudios se utilizaron diseños de muestreo BACI y mBACI. A través de esta revisión, se han identificado deficiencias en los objetivos de las AMPs y en la manera como han sido evaluados. Como conclusión sugerimos algunas pautas para mejorar la evaluación de los efectos de la protección en estas zonasPublicado

The Spanish Pancreatic Club recommendations for the diagnosis and treatment of chronic pancreatitis: Part 1 (diagnosis)

Chronic pancreatitis (CP) is a relatively uncommon, complex and heterogeneous disease. The absence of a gold standard applicable to the initial phases of CP makes its early diagnosis difficult. Some of its complications, particularly chronic pain, can be difficult to manage. There is much variability in the diagnosis and treatment of CP and its complications amongst centers and professionals. The Spanish Pancreatic Club has developed a consensus on the management of CP. Two coordinators chose a multidisciplinary panel of 24 experts on this disease. A list of questions was drafted, and two experts reviewed each question. Then, a draft was produced and shared with the entire panel of experts and discussed in a face-to-fac

Eventos adversos evitables en atención primaria. Estudio retrospectivo de cohortes para determinar su frecuencia y gravedad

Objetivo: Determinar la frecuencia de eventos adversos evitables (EAE) en atención primaria (AP). Diseño: Estudio retrospectivo de cohortes. Emplazamiento: consultas de medicina de familia y pediatría de Andalucía, Aragón, Castilla La Mancha, Cataluña, Madrid, Navarra y Comunidad Valenciana. Participantes: Se determinó revisar un mínimo de 2.397 historias clínicas (nivel de confianza del 95% y una precisión del 2%). La muestra se estratificó por grupos de edad de forma proporcional a su frecuentación y con revisión paritaria de historias de hombres y mujeres. Mediciones principales: Número y gravedad de los EAE identificados entre febrero de 2018 y septiembre de 2019. Resultados: Se revisaron un total de 2.557 historias clínicas (1.928, 75.4% de pacientes adultos y 629, 24.6% pediátricos). Se identificaron 182 EAE que afectaron a 168 pacientes (7,1%, IC 95% 6,1-8,1%); en adultos 7,6% (IC 95% 6,4-8,8%) y 5,7% (IC 95% 3,9-7,5%) en pacientes pediátricos. Las mujeres sufrieron más EAE que los hombres (p = 0,004). La incidencia de EAE en niños y niñas fue similar (p = 0,3). 6 (4.1%) de los EAE supusieron un daño permanente en pacientes adultos. Conclusiones: Buscar fórmulas para incrementar la seguridad en AP, particularmente en pacientes mujeres, debe seguir siendo un objetivo prioritario incluso en pediatría. Uno de cada 24 EAE supone un daño grave y permanente en el adulto

Multiancestry analysis of the HLA locus in Alzheimer’s and Parkinson’s diseases uncovers a shared adaptive immune response mediated by HLA-DRB1*04 subtypes

Across multiancestry groups, we analyzed Human Leukocyte Antigen (HLA) associations in over 176,000 individuals with Parkinson’s disease (PD) and Alzheimer’s disease (AD) versus controls. We demonstrate that the two diseases share the same protective association at the HLA locus. HLA-specific fine-mapping showed that hierarchical protective effects of HLA-DRB1*04 subtypes best accounted for the association, strongest with HLA-DRB1*04:04 and HLA-DRB1*04:07, and intermediary with HLA-DRB1*04:01 and HLA-DRB1*04:03. The same signal was associated with decreased neurofibrillary tangles in postmortem brains and was associated with reduced tau levels in cerebrospinal fluid and to a lower extent with increased Aβ42. Protective HLA-DRB1*04 subtypes strongly bound the aggregation-prone tau PHF6 sequence, however only when acetylated at a lysine (K311), a common posttranslational modification central to tau aggregation. An HLA-DRB1*04-mediated adaptive immune response decreases PD and AD risks, potentially by acting against tau, offering the possibility of therapeutic avenues