Recursos de osteosíntesis en fémur porótico.

Objetivos. Exponer dos técnicas quirúrgicas de refuerzo de una osteosíntesis convencional en situaciones especiales de debilidad ósea del fémur, como son las fracturas periprotésicas, las fracturas patológicas y los fracasos de osteosíntesis previas en pacientes de edad avanzada. La debilidad del hueso puede llegar a dificultar la realización de osteosíntesis estables en fracturas de fémur porque impide el correcto anclaje del material, ya sean agujas, cerclajes o especialmente tornillos. Material y método. Se evaluaron 13 pacientes (media de edad de 78,3 años), 9 de los cuales sufrieron fracturas periprotésicas de fémur, dos fracasos de osteosíntesis previas, un caso de pseudoartrosis tras una fractura periprotésica y una fractura diafisaria en un fémur muy osteoporótico, en los cuales se han utilizado dos técnicas de refuerzo del hueso: el cementado endomedular y el implante de contraplacas atornilladas de aloinjerto óseo congelado. Resultados. Se realizó un seguimiento de estos pacientes en un período que oscila entre 12 y 72 meses (media de 26,2 meses). En un caso se produjo una pseudoartrosis de la fractura por ocupación accidental del foco de fractura por el cemento acrílico. En los 12 casos restantes se consiguió la consolidación. Conclusiones. El cementado endomedular y la utilización de contraplacas atornilladas de aloinjerto óseo son dos recursos técnicos útiles en situaciones especiales en las que es necesario realizar una osteosíntesis estable sobre un hueso muy débil

Crucial role of calbindin-D28k in the pathogenesis of Alzheimer's disease mouse model

Calbindin-D28k (CB), one of the major calcium-binding and buffering proteins, has a critical role in preventing a neuronal death as well as maintaining calcium homeostasis. Although marked reductions of CB expression have been observed in the brains of mice and humans with Alzheimer disease (AD), it is unknown whether these changes contribute to AD-related dysfunction. To determine the pathogenic importance of CB depletions in AD models, we crossed 5 familial AD mutations (5XFAD; Tg) mice with CB knock-out (CBKO) mice and generated a novel line CBKO·5XFAD (CBKOTg) mice. We first identified the change of signaling pathways and differentially expressed proteins globally by removing CB in Tg mice using mass spectrometry and antibody microarray. Immunohistochemistry showed that CBKOTg mice had significant neuronal loss in the subiculum area without changing the magnitude (number) of amyloid β-peptide (Aβ) plaques deposition and elicited significant apoptotic features and mitochondrial dysfunction compared with Tg mice. Moreover, CBKOTg mice reduced levels of phosphorylated mitogen-activated protein kinase (extracellular signal-regulated kinase) 1/2 and cAMP response element-binding protein at Ser-133 and synaptic molecules such as N-methyl-D-aspartate receptor 1 (NMDA receptor 1), NMDA receptor 2A, PSD-95 and synaptophysin in the subiculum compared with Tg mice. Importantly, this is the first experimental evidence that removal of CB from amyloid precursor protein/presenilin transgenic mice aggravates AD pathogenesis, suggesting that CB has a critical role in AD pathogenesis

Involvement of cell surface TG2 in the aggregation of K562 cells triggered by gluten

Gluten-induced aggregation of K562 cells represents an in vitro model reproducing the early steps occurring in the small bowel of celiac patients exposed to gliadin. Despite the clear involvement of TG2 in the activation of the antigen-presenting cells, it is not yet clear in which compartment it occurs. Herein we study the calcium-dependent aggregation of these cells, using either cell-permeable or cell-impermeable TG2 inhibitors. Gluten induces efficient aggregation when calcium is absent in the extracellular environment, while TG2 inhibitors do not restore the full aggregating potential of gluten in the presence of calcium. These findings suggest that TG2 activity is not essential in the cellular aggregation mechanism. We demonstrate that gluten contacts the cells and provokes their aggregation through a mechanism involving the A-gliadin peptide 31-43. This peptide also activates the cell surface associated extracellular TG2 in the absence of calcium. Using a bioinformatics approach, we identify the possible docking sites of this peptide on the open and closed TG2 structures. Peptide docks with the closed TG2 structure near to the GTP/GDP site, by establishing molecular interactions with the same amino acids involved in stabilization of GTP binding. We suggest that it may occur through the displacement of GTP, switching the TG2 structure from the closed to the active open conformation. Furthermore, docking analysis shows peptide binding with the β-sandwich domain of the closed TG2 structure, suggesting that this region could be responsible for the different aggregating effects of gluten shown in the presence or absence of calcium. We deduce from these data a possible mechanism of action by which gluten makes contact with the cell surface, which could have possible implications in the celiac disease onset

Female Genital Mutilation: perceptions of healthcare professionals and the perspective of the migrant families

<p>Abstract</p> <p>Background</p> <p>Female Genital Mutilation (FGM) is a traditional practice which is harmful to health and is profoundly rooted in many Sub-Saharan African countries. It is estimated that between 100 and 140 million women around the world have been victims of some form of FGM and that each year 3 million girls are at risk of being submitted to these practices. As a consequence of the migratory phenomena, the problems associated with FGM have extended to the Western countries receiving the immigrants. The practice of FGM has repercussions on the physical, psychic, sexual and reproductive health of women, severely deteriorating their current and future quality of life. Primary healthcare professionals are in a privileged position to detect and prevent these situations of risk which will be increasingly more present in Spain.</p> <p>Methods/Design</p> <p>The objective of the study is to describe the knowledge, attitudes and practices of the primary healthcare professionals, working in 25 health care centres in Barcelona and Girona regions, regarding FGM, as well as to investigate the perception of this subject among the migrant communities from countries with strong roots in these practices. A transversal descriptive study will be performed with a questionnaire to primary healthcare professionals and migrant healthcare users.</p> <p>Using a questionnaire specifically designed for this study, we will evaluate the knowledge, attitudes and skills of the healthcare professionals to approach this problem. In a sub-study, performed with a similar methodology but with the participation of cultural mediators, the perceptions of the migrant families in relation to their position and expectancies in view of the result of preventive interventions will be determined.</p> <p>Variables related to the socio-demographic aspects, knowledge of FGM (types, cultural origin, geographic distribution and ethnicity), evaluation of attitudes and beliefs towards FGM and previous contact or experience with cases or risk situations will be obtained.</p> <p>Discussion</p> <p>Knowledge of these harmful practices and a preventive approach from a transcultural perspective may represent a positive intervention model for integrative care of immigrants, respecting their values and culture while also being effective in eliminating the physical and psychic consequences of FGM.</p

European Competitiveness: A Semi-Parametric Stochastic Metafrontier Analysis at the Firm Level

In this paper a semiparametric stochastic metafrontier approach is used to obtain insight into firm-level competitiveness in Europe. We divert from standard TFP studies at the firm level as we simultaneously allow for inefficiency, noise and do not impose a functional form on the input-output relation. Using AMADEUS firm-level data covering 10 manufacturing sectors from seven EU15 countries, (i) we document substantial, persistent divergences in competitiveness (with Belgium and Germany as benchmark countries and Spain lagging behind) and a wide technology gap, (ii) we confirm the absence of convergence in TFP between the seven selected countries, (iii) we confirm that the technology gap is more pronounced for smaller firms, (iv) we highlight the role of post-entry growth for competitiveness

Productive Development Policies in Latin American Countries: The Case of Peru, 1990-2007

This paper assesses the institutional setting and productive impact of selected productive development policies (PDPs), institutions, and programs implemented in Peru during the period 1990-2007. The assessment is based on a simple, basic framework of a series of economic or market failures that may have constrained the transformation of the productive structure, the process of innovation, and the growth of total factor productivity. Evidence indicates that the PDPs and structural reforms implemented in Peru did not significantly alter the productive structure of the Peruvian economy. If the objectives of the PDPs are to transform the productive structure, increase total factor productivity, and enhance innovation, government interventions need to focus directly on the source of market failures and create quality productive changes within the private sector

Microstructure, thermo-mechanical properties and Portevin-Le Chatelier effect in metastable β Ti-xMo alloys

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Spatiotemporal characteristics of Portevin-Le Chatelier effect in Ti-Mo alloys under thermo-mechanical loading

International audienceThe Portevin-Le Chaterlier (PLC) effect in Ti-12Mo and Ti-15Mo alloys has been investigated by using uniaxial tensile tests in a temperature range of 25–350 °C with an applied strain rate of the order of 10−3 s−1, coupled with a digital image correlation (DIC) method. The experimental results show an increase of the yield stress from 25 °C to 250 °C followed by a decrease. Moreover, PLC effect occurs above 250 °C and stress drop magnitude increases while the number of stress drops per unit time decreases with increasing the strain and temperature as well as decreasing Mo contents. These macroscopic features are related to the reduced intensity of interactions between ω phase particles and mobile dislocations as decreasing temperature and increasing Mo contents. Furthermore, a relatively higher temperature and lower Mo content tend to weaken the spatial cohesion of propagation bands and strengthen strain localization, leading to a change of PLC bands from type A to type B and the increase of strain rate within the PLC bands, which are related to the increased precipitation of ω phases. Additionally, the elongation at fracture is significantly influenced by PLC effect in Ti-Mo alloys

Towards self-alignment with copper pillars

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