69 research outputs found

    Influence of Surface Finishes and a Calcium Phosphate-Based Consolidant on the Decay of Sedimentary Building Stones Due to Acid Attack

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    Natural stone has long been used as a building material because of its physical-mechanical resistance and its esthetic appeal. However, over the last century increasing industrial activity has produced more acidic environments, such as polluted urban areas, that can cause serious damage to many buildings and historic monuments, and in particular those made with carbonate rocks, which are most prone to decay. In order to mitigate the physicochemical processes that degrade these buildings, a number of phosphate-based consolidants have been developed, which are highly compatible with the carbonated substrate. Research about the role of the surface and its different possible finishes in the transmission of the agents that damage or protect the stone would therefore be very useful, both when choosing the most suitable stone for new constructions and when restoring historic buildings. The main objective of this research was to determine whether the roughness of three types of surface finish (saw-cut, honed and bush-hammered) influences the durability of four types of natural stone (two calcarenites, one travertine and one sandstone) widely used in Andalusia (Spain). The efficacy of a calcium phosphate-based consolidant as a mitigator of deterioration in polluted urban environments was also studied and to this end the physical properties of untreated and treated samples were measured and compared. The samples were exposed to artificial atmospheres with SO2 pollution in order to assess the damage caused to each surface finish. The results indicate that all the surface finishes were vulnerable to the decay caused by acidic atmospheres, although the saw-cut finish was less affected, perhaps because it did not require additional industrial processing. The mineral composition and texture of the rocks were critical factors in terms of the amount and type of decay they suffered, and the travertine and sandstone were more resistant to deterioration than the calcarenites. Similarly, the pore system of each rock was decisive in the penetration of the consolidant. Application of the consolidant improved the behavior of the treated samples by making them more resistant to acid attack without significantly altering the water vapor permeability, the color or the roughness of the surface

    A zebrafish functional genomics model to investigate the role of human A20 variants in vivo

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    Germline loss-of-function variation in TNFAIP3, encoding A20, has been implicated in a wide variety of autoinflammatory and autoimmune conditions, with acquired somatic missense mutations linked to cancer progression. Furthermore, human sequence data reveals that the A20 locus contains ~ 400 non-synonymous coding variants, which are largely uncharacterised. The growing number of A20 coding variants with unknown function, but potential clinical impact, poses a challenge to traditional mouse-based approaches. Here we report the development of a novel functional genomics approach that utilizes a new A20-deficient zebrafish (Danio rerio) model to investigate the impact of TNFAIP3 genetic variants in vivo. A20-deficient zebrafish are hyper-responsive to microbial immune activation and exhibit spontaneous early lethality. Ectopic addition of human A20 rescued A20-null zebrafish from lethality, while missense mutations at two conserved A20 residues, S381A and C243Y, reversed this protective effect. Ser381 represents a phosphorylation site important for enhancing A20 activity that is abrogated by its mutation to alanine, or by a causal C243Y mutation that triggers human autoimmune disease. These data reveal an evolutionarily conserved role for TNFAIP3 in limiting inflammation in the vertebrate linage and show how this function is controlled by phosphorylation. They also demonstrate how a zebrafish functional genomics pipeline can be utilized to investigate the in vivo significance of medically relevant human TNFAIP3 gene variants.Daniele Cultrone, Nathan W. Zammit, Eleanor Self, Benno Postert, Jeremy Z. R. Han, Jacqueline Bailey ... et al

    The Influence of the Type of Lime on the Hygric Behaviour and Bio-Receptivity of Hemp Lime Composites Used for Rendering Applications in Sustainable New Construction and Repair Works

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    The benefits of using sustainable building materials are linked not only to the adoption of manufacturing processes that entail reduced pollution, CO2 emissions and energy consumption, but also to the onset of improved performance in the building. In particular, hemp-lime composite shows low shrinkage and high thermal and acoustic insulating properties. However, this material also shows a great ability to absorb water, an aspect that can turn out to be negative for the long-term durability of the building. For this reason, the hygric properties of hemp-based composites need to be studied to ensure the correct use of this material in construction and repair works. The water absorption, drying and transpirability of hemp composites made with aerial (in the form of dry powder and putty) and hydraulic limes were investigated here and related to the microbial growth induced by the water movements within the material. Results show that hemp-natural hydraulic lime mixes exhibit the highest transpirability and drying rate, the lowest water absorption by immersion and capillary uptake and the least intense microbial attack and chromatic change. A microscopical study of the hemp shives also related their great ability to absorb water to the near-irreversible swelling of their structure under dry-wet conditions.The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 326983 (NaturALiMe), and the Spanish project MAT-2012-34473 of the Ministerio de Ciencia y Competitividad. Author MB, owner of the CANNABRIC company, had some role in the design and preparation of mortar samples and in the preparation of this manuscript, but did not have any additional role in data collection and analysis

    Approaches in biotechnological applications of natural polymers

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    Natural polymers, such as gums and mucilage, are biocompatible, cheap, easily available and non-toxic materials of native origin. These polymers are increasingly preferred over synthetic materials for industrial applications due to their intrinsic properties, as well as they are considered alternative sources of raw materials since they present characteristics of sustainability, biodegradability and biosafety. As definition, gums and mucilages are polysaccharides or complex carbohydrates consisting of one or more monosaccharides or their derivatives linked in bewildering variety of linkages and structures. Natural gums are considered polysaccharides naturally occurring in varieties of plant seeds and exudates, tree or shrub exudates, seaweed extracts, fungi, bacteria, and animal sources. Water-soluble gums, also known as hydrocolloids, are considered exudates and are pathological products; therefore, they do not form a part of cell wall. On the other hand, mucilages are part of cell and physiological products. It is important to highlight that gums represent the largest amounts of polymer materials derived from plants. Gums have enormously large and broad applications in both food and non-food industries, being commonly used as thickening, binding, emulsifying, suspending, stabilizing agents and matrices for drug release in pharmaceutical and cosmetic industries. In the food industry, their gelling properties and the ability to mold edible films and coatings are extensively studied. The use of gums depends on the intrinsic properties that they provide, often at costs below those of synthetic polymers. For upgrading the value of gums, they are being processed into various forms, including the most recent nanomaterials, for various biotechnological applications. Thus, the main natural polymers including galactomannans, cellulose, chitin, agar, carrageenan, alginate, cashew gum, pectin and starch, in addition to the current researches about them are reviewed in this article.. }To the Conselho Nacional de Desenvolvimento Cientfíico e Tecnológico (CNPq) for fellowships (LCBBC and MGCC) and the Coordenação de Aperfeiçoamento de Pessoal de Nvíel Superior (CAPES) (PBSA). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, the Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and COMPETE 2020 (POCI-01-0145-FEDER-006684) (JAT)

    The Coastal Sediment Provenance and Their Distribution in the Mediterranean Beaches of NW Morocco

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    This work deals with the granulometric and geochemical features of sediments collected at the foreshore of Tetouan beaches (NW Morocco) and at the mouth of the local five main watercourses in order to establish the links between the continental and coastal areas. The littoral, which underwent a great increase of human pressure in past decades, records great erosion rates that menace different human settlements and natural features of great environmental importance such as dune ridges, fossil cliffs and coastal lagoon. Specifically, the analysis of sediment samples collected along the Tetouan littoral made possible the characterization of the transport and depositional environments as well as the determination of sediment characteristics that are closely related to the geology and hydrology of adjacent basin areas and the relationship among long shore transport and the influence of human activities and natural coastal features that influence the geochemical composition of coastal sediments. The sedimentological studies support coastal monitoring programs for suitable coastal protection and beach nourishment projects. Analyzed beach sediments are essentially composed by quartz-rich sand and can be clearly distinguished two different sectors: (i) the first one, between Ras Mazari and Cabo Negro headlands, is characterized by medium sand, from well to very well-sorted, main sedimentary supplies to the littoral being provided by Martil River; (ii) the second one, between Cabo Negro and Ceuta headlands, consists of coarse to very coarse sediments, poorly sorted, main sedimentary inputs being related to biogenic sources and to the erosion of metamorphic rocks from Cabo Negro headland

    Novel single-nucleotide polymorphisms in the calsequestrin-1 gene are associated with Graves’ ophthalmopathy and Hashimoto’s thyroiditis

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    Hooshang Lahooti,1,2 Daniele Cultrone,1,2 Senarath Edirimanne,1,2 John P Walsh,3,4 Leigh Delbridge,5,6 Patrick Cregan,1,2 Bernard Champion,1,2 Jack R Wall1,21Thyroid Research Laboratory, Sydney Medical School – Nepean Clinical School, The University of Sydney, 2Nepean Blue Mountains Local Health District, Nepean Hospital, Kingswood, NSW, 3Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, 4School of Medicine and Pharmacology, The University of Western Australia, Crawley, WA, 5Department of Surgery, Royal North Shore Hospital, 6Sydney Medical School – Northern Clinical School, The University of Sydney, St Leonards, NSW, AustraliaBackground: The eye disorder associated with Graves’ disease, called Graves’ ophthalmopathy (GO), greatly reduces the quality of life in affected patients. Expression of the calsequestrin (CASQ1) protein in thyroid tissue may be the trigger for the development of eye muscle damage in patients with GO. We determined the prevalence of rs74123279, rs3747673, and rs2275703 single-nucleotide polymorphism (SNPs) in patients with autoimmune thyroid disorders, GO, Graves’ hyperthyroidism (GH), or Hashimoto’s thyroiditis (HT) and control subjects with no personal or family history of autoimmune thyroid disorders. Furthermore, we measured the concentration of the CASQ1 protein in normal and Graves’ thyroid tissue, correlating levels with parameters of the eye signs, CASQ1 antibody levels, and the CASQ1 gene polymorphism rs74123279 and rs2275703.Methods: High-quality genomic DNA was isolated from fresh blood samples, assayed for identification of rs74123279, rs3747673, and rs2275703 SNPs in CASQ1 gene by MassARRAY SNP analysis using iPLEX technology of SEQUENOM.Results: DNA samples from 300 patients and 106 control subjects (100 males, 306 females) with GO (n=74), GH (n=130), HT (n=96) and control subjects (n=106) were genotyped for the SNPs rs74123279, rs3747673 (n=405), and rs2275703 (n=407). The SNP rs74123279, rs3747673, and rs2275703 were identified as 1) common homozygous or wild type, 2) heterozygote, and 3) rare homozygous. Minor allele frequency for rs74123279, rs3747763, and rs2275703 were 21%, 40%, and 44%, respectively. Multiple comparisons of genotype frequency for rs74123279, rs3747763, and rs2275703 in the GO, GH, HT, and control groups showed P=0.06, 0.641, and 0.189, respectively. These results were substantiated by multiple comparison of alleles frequency for rs74123279, rs3838216, rs3747763, and rs2275703 in the GO, GH, HT, and control groups showed, P=0.36, 0.008, 0.66, and 0.05, respectively. Pairwise analysis of alleles frequency distribution in patients with GO showed significant probability for rs2275703, P=0.008.Conclusion: Based on their evolutionary conservation and their significant prevalence, we suggest that CASQ1 gene SNPs rs74123279, rs3838216, and rs2275703 may be considered as genetic markers for GO.Keywords: thyroid eye disease, autoimmune thyroiditis, ophthalmology, orbitopathy, eye muscles antibodies, wild-type, homozygous, heterozygous, genotypin

    Selection of a novel AAV2/TNFAIP3 vector for local suppression of islet xenograft inflammation

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    Background: Neonatal porcine islets (NPIs) can restore glucose control in mice, pigs, and non-human primates, representing a potential abundant alternative islet supply for clinical beta cell replacement therapy. However, NPIs are vulnerable to inflammatory insults that could be overcome with genetic modifications. Here, we demonstrate in a series of proof-of-concept experiments the potential of the cytoplasmic ubiquitin-editing protein A20, encoded by the TNFAIP3 gene, as an NPI cytoprotective gene. Methods: We forced A20 expression in NPI grafts using a recombinant adenovirus 5 (Ad5) vector and looked for impact on TNF-stimulated NF-ÎșB activation and NPI graft function. As adeno-associated vectors (AAV) are clinically preferred vectors but exhibit poor transduction efficacy in NPIs, we next screened a series of AAV serotypes under different transduction protocols for their ability achieve high transduction efficiency and suppress NPI inflammation without impacting NPI maturation. Results: Forcing the expression of A20 in NPI with Ad5 vector blocked NF-ÎșB activation by inhibiting IÎșBα phosphorylation and degradation, and reduced the induction of pro-inflammatory genes Cxcl10 and Icam1. A20-expressing NPIs also exhibited superior functional capacity when transplanted into diabetic immunodeficient recipient mice, evidenced by a more rapid return to euglycemia and improved GTT compared to unmodified NPI grafts. We found AAV2 combined with a 14-day culture period maximized NPI transduction efficiency (>70% transduction rate), and suppressed NF-ÎșB-dependent gene expression without adverse impact upon NPI maturation. Conclusion: We report a new protocol that allows for high-efficiency genetic modification of NPIs, which can be utilized to introduce candidate genes without the need for germline engineering. This approach would be suitable for preclinical and clinical testing of beneficial molecules. We also report for the first time that A20 is cytoprotective for NPI, such that A20 gene therapy could aid the clinical development of NPIs for beta cell replacement.Nathan W. Zammit, Karen L. Seeberger, Jad Zamerli, Stacey N. Walters, Leszek Lisowski, Gregory S. Korbutt, Shane T. Gre
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