91 research outputs found

    Influence of homogenization conditions on physical properties and antioxidant activity of fully biodegradable pea protein-alpha-tocopherol films

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    In this study, antioxidant biodegradable films based on pea protein and alpha-tocopherol were successfully developed by solution casting. The effect of both the homogenization conditions (rotor stator and microfluidizer) and the relative humidity (RH) on the microstructure and physical properties (transparency, tensile, oxygen and water vapour barrier properties) of pea protein/alpha-tocopherol-based films was evaluated. The addition of alpha-tocopherol produced minimal changes in the films transparency, while providing them with antioxidant properties and improved water vapour and oxygen barrier properties (up to 30 % in both water vapour and oxygen permeability) when films were at low and intermediate RH. The addition of alpha-tocopherol in microfluidized films gave rise to an increase in their resistance to break and extensibility (up to 27 % in E values) at intermediate and high RH. These results add a new insight into the potential of employing pea protein and alpha-tocopherol in the development of fully biodegradable antioxidant films which are of interest in food packagingThe authors acknowledge the financial support from the Spanish Ministerio de Educacion y Ciencia throughout the project AGL2010-20694, co-funded by FEDER. Author M.J.Fabra is a recipient of a Juan de la Cierva contract from the Spanish Ministerio de Economia y Competitividad.Fabra, MJ.; JimĂ©nez, A.; Talens Oliag, P.; Chiralt, A. (2014). Influence of homogenization conditions on physical properties and antioxidant activity of fully biodegradable pea protein-alpha-tocopherol films. Food and Bioprocess Technology. 7(12):3569-3578. https://doi.org/10.1007/s11947-014-1372-0S35693578712ASTM (1995). Standard test methods for water vapor transmission of materials. Standards Desingnations: E96-95. 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    Toward a Comprehensive Approach to the Collection and Analysis of Pica Substances, with Emphasis on Geophagic Materials

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    Pica, the craving and subsequent consumption of non-food substances such as earth, charcoal, and raw starch, has been an enigma for more than 2000 years. Currently, there are little available data for testing major hypotheses about pica because of methodological limitations and lack of attention to the problem.In this paper we critically review procedures and guidelines for interviews and sample collection that are appropriate for a wide variety of pica substances. In addition, we outline methodologies for the physical, mineralogical, and chemical characterization of these substances, with particular focus on geophagic soils and clays. Many of these methods are standard procedures in anthropological, soil, or nutritional sciences, but have rarely or never been applied to the study of pica.Physical properties of geophagic materials including color, particle size distribution, consistency and dispersion/flocculation (coagulation) should be assessed by appropriate methods. Quantitative mineralogical analyses by X-ray diffraction should be made on bulk material as well as on separated clay fractions, and the various clay minerals should be characterized by a variety of supplementary tests. Concentrations of minerals should be determined using X-ray fluorescence for non-food substances and inductively coupled plasma-atomic emission spectroscopy for food-like substances. pH, salt content, cation exchange capacity, organic carbon content and labile forms of iron oxide should also be determined. Finally, analyses relating to biological interactions are recommended, including determination of the bioavailability of nutrients and other bioactive components from pica substances, as well as their detoxification capacities and parasitological profiles.This is the first review of appropriate methodologies for the study of human pica. The comprehensive and multi-disciplinary approach to the collection and analysis of pica substances detailed here is a necessary preliminary step to understanding the nutritional enigma of non-food consumption

    Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

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    In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field

    Behavioral Economics and the Public Sector

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    This thesis consists of four essays dealing with topics that are relevant for the public sector. The essays cover diverse issues of economics partly overlapping with political science. The topics reach from the taxation of labor over monetary policy to preferences over voting institutions. Throughout this thesis it is, in contrast to classical economics, not assumed that humans are necessarily fully rational. Once full rationality is no longer assumed, experiments become an important tool to learn about human behavior. Consequently, most of the work in this thesis makes use of economic experiments

    Current and emerging systemic treatments targeting the neural system for chronic pruritus

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    Pruritus is a debilitating symptom that significantly affects the quality of life of patients who suffer from it. Many current and emerging systemic treatments targeting the neural system have been successful in treating itch of various underlying etiologies. A complete search of the PUBMED and Google Scholar databases was completed and literature pertinent to current and emerging systemic anti-pruritic drugs which target the neural system was compiled. The purpose of this review is to give the reader with an overview of the current and emerging systemic therapeutic options which target the neural system for chronic pruritus. The authors then provide the reader with their expert perspectives on the future of these therapies. Exciting new anti-pruritic therapies targeting the neural system which show promise include NK-1 inhibitors, opioid receptor modulators, and drugs targeting specific itch receptors such as Mrgpr, Na v 1.7, and PAR2, as well as selective GABA modulators. Future studies should be conducted in order to fully understand these exciting therapeutic options

    The Hd, Hj, and Hz66 flagella variants of Salmonella enterica serovar Typhi modify host responses and cellular interactions.

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    Salmonella Typhi, the causative agent of typhoid fever, is a monophyletic, human-restricted bacterium that exhibits limited phenotypic variation. S. Typhi from Indonesia are a notable exception, with circulating strains expressing diverse flagella antigens including Hj, Hd and Hz66. Hypothesizing that S. Typhi flagella plays a key role during infection, we constructed an S. Typhi fliC mutant and otherwise isogenic S. Typhi strains expressing the Hj, Hd, Hz66 flagella antigens. Phenotyping revealed differences in flagellum structure, strain motility and immunogenicity, but not in the ability of flagellated isolates to induce TLR5 activity. Invasion assays using epithelial and macrophage cell lines revealed differences in the ability of these S. Typhi derivatives to invade cells or induce cellular restructuring in the form of ruffles. Notably, the Hj variant induced substantial ruffles that were not fully dependent on the GTPases that contribute to this process. These data highlight important differences in the phenotypic properties of S. Typhi flagella variation and how they impact on the pathogenesis of S. Typhi
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