Variants of Hepcidin Gene Promoter Modulate Iron Status in H63d Individuals

Background: HFE is a major histocompatibility complex class I-like protein that is mutated in Hereditary Hemochromatosis (HH). Despite C282Y being the most common HH-associated HFE mutation, there are other reported mutations, such as H63D, with an uncertain role in the pathogenesis of the disease. Hepcidin is a crucial regulator of systemic iron homeostasis, controlling the absorption of iron by enterocytes and its release by macrophages. Mutations in this gene (HAMP) result in the development of a juvenile type of HH. Also, it has been shown that a polymorphism in HAMP promoter (c.-582A>G) is associated with an increase of serum ferritin levels in beta-thalassemia major patients but not in normal individuals. Objectives/Methods: We screened for the presence of polymorphisms in the HAMP promoter in 266 individuals with ferritin levels higher than 400ng/mL, being: i) 191 individuals homozygous or heterozygous for the H63D mutation (group 1) and ii) 75 individuals carrying one or more C282Y alleles (HH/CY, HH/YY or HD/CY), (group 2). To assess whether HAMP promoter polymorphisms are changing the hepcidin expression in response to an external stimulus we performed luminescence assays in Huh-7 cell line. Results: Our data show that, in our sample, the c.-582A>G polymorphism is in linkage with another one, the c.-1010C>T. These polymorphisms were found in a significant higher frequency in group 1 (31.2% of allele G and T, respectively) than in the general population (16.4%; p<0.001). On the contrary, they were found at a slight higher, but not significant, frequency at group 2 (21.3%), comparing with general population (p=0.186). Functional in vitro studies, using stimulus as holo-transferrin, ferric citrate, IL-6 or GDF15, revealed no differences in the activity of the HAMP promoter in the presence or absence of the polymorphisms. However, further analysis with some other stimuli, such as hypoxia or BMPs must be performed. Conclusions: c.-582A>G/c.-1010C>T polymorphisms seem to be modulators of iron overload development in individuals carrying the H63D mutation. However, the mechanism subjacent to this observation remains elusive.Parcialmente financiado por FCT: Programa de Financiamento Plurianual do CIGMH e Bolsa de Doutoramento SFRH/BD/60718/2009

Comparison between heat treated sapwood and heartwood from Pinus pinaster

Sapwood and heartwood samples of Pinus pinaster were treated in an oven at 190ºC and 200ºC for 2-6h. Dimensional stability, measured as Anti Shrinking Efficiency (ASE) between 0% and 65% relative humidity, durability against fungi, mechanical resistance (MOE and MOR), hardness and chemical composition were determined for treated and untreated sapwood and heartwood. Radial ASE reached 52% for sapwood and 50% for heartwood while tangential ASE reached 50% and 40% respectively. MOE increased slightly at the beginning of the treatment decreasing afterwards. No significant differences were found between sapwood and heartwood. MOR decreased by 50% and 30% for sapwood and heartwood respectively. A significant increase in durability against Rhodonia placenta was found for both heartwood and sapwood at the higher temperature and for heartwood only at 190º for 4h.info:eu-repo/semantics/publishedVersio

State of the art of industrial wood protection in Portugal

This work intended to give a perspective of industrial wood protection in Portugal. A survey was made of the companies treating wood mainly for use classes 3 and 4 such as autoclave treatments with biocides and wood modification procedures. Currently there are 23 companies with 33 production plants with an autoclave installed for wood preservation by impregnation. There are also two companies producing modified wood by thermal treatment. Most of the plants are located in the central and northern regions of Portugal. The leading preservation chemicals used in Portugal are Tanalith E and Celcure brands. The main wood species used in all companies is Pinus pinaster from local producers. The products commercialized by the treating companies are diverse: pre-fabricated houses, garden furniture and playgrounds, decks, poles, stakes, and sawn wood. Modified wood producers sell mostly decks and cladding. Considerable changes are expected in the next few years due to the requirements of European Directives and the typical constraints of the Portuguese market.info:eu-repo/semantics/publishedVersio

Improvement of termite resistance, dimensional stability and mechanical properties of pine wood by paraffin impregnation

Paraffin has been used as surface protection of wood throughout the ages but its use for impregnation to improve wood resistance to biodegradation is recent. This study determined the main improvements on wood properties with paraffin impregnation. Healthy Pinus pinaster Ait. wood was impregnated with paraffin at different levels using a hot–cold process. Weight gain, equilibrium moisture content and dimensional stability (ASE) at 35 and 65 % relative humidity, termite durability against Reticulitermes grassei (Clément), bending strength, bending stiffness (MOE) and Janka hardness were determined. Density increased from 0.57 to 0.99, ASE ranged between 38–96 % and 16–71 % for 35 and 65 % relative humidity, respectively. Equilibrium moisture content decreased from 9.9 and 12.0 % to 0.8 and 3.6 % for 35 and 65 % relative humidity. Termite durability improved from level 4 to level 3 of attack, and higher termite mortality was found in treated wood (52 % against 17 %). Bending strength (MOR) increased with paraffin weight gain, reaching a 39 % increase. MOE also increased by about 13 % for wood with a weight gain around 80 %. Janka hardness increased significantly reaching about 40 % for wood with 80 % weight gain. Paraffin impregnated wood has improved properties with regard to equilibrium moisture content, dimensional stability and density, bending strength and Janka hardness, and resistance against termites

Link Prediction via Community Detection in Bipartite Multi-Layer Graphs

International audienceThe growing number of multi-relational networks pose new challenges concerning the development of methods for solving classical graph problems in a multi-layer framework, such as link prediction. In this work, we combine an existing bipartite local models method with approaches for link prediction from communities to address the link prediction problem in multi-layer graphs. To this end, we extend existing community detection-based link prediction measures to the bipartite multi-layer network setting. We obtain a new generic framework for link prediction in bipartite multi-layer graphs, which can integrate any community detection approach, is capable of handling an arbitrary number of networks, rather inexpensive (depending on the community detection technique), and able to automatically tune its parameters. We test our framework using two of the most common community detection methods, the Louvain algorithm and spectral partitioning, which can be easily applied to bipartite multi-layer graphs. We evaluate our approach on benchmark data sets for solving a common drug-target interaction prediction task in computational drug design and demonstrate experimentally that our approach is competitive with the state-of-the-art

Hepcidin Gene Promoter c.-1010T and c.-582G Variants are Modulators of Iron Overload Development in Individuals Carrying the H63D Mutation in the HFE Gene

Mutated HFE gene/protein is usually associated with Hereditary Hemochromatosis (HH). Despite C282Y being the most common HH-associated HFE mutation, others, such as H63D, also have an uncertain role in the pathogenesis of HH. Hepcidin is a crucial regulator of systemic iron homeostasis, controlling both iron absorption by enterocytes and its release by macrophages. Mutations in Hepcidin gene (HAMP) result in the development of a juvenile type of HH. Also, it has been hypothesized that, in certain conditions, some HAMP polymorphisms can modulate iron status. As example, c.-582A>G polymorphism in HAMP promoter can increase serum ferritin levels in beta-thalassemia major patients, but not in normal individuals. HAMP promoter polymorphisms were analysed by DNA sequencing in 266 individuals with ferritin levels higher than 400ng/mL: i) 191 individuals homozygous or heterozygous for the H63D mutation (group 1) and ii) 75 individuals carrying one or more C282Y alleles (HH/CY, HH/YY or HD/CY) (group 2). Also, luminescence assays were performed in Huh-7 cells in order to assess whether the HAMP promoter polymorphisms are changing the hepcidin expression in response to external stimulus. The results revealed that c.-582A>G is in linkage with c.-1010C>T polymorphism. These polymorphisms were found in a significant higher frequency in group 1 (31.2% of allele G and T, respectively) than in the general population (16.4%; p<0.001). Furthermore, they were found at a slight higher, but not significant frequency at group 2 (21.3%), comparing with general population (p=0.186). Functional in vitro studies, using stimulus as holo-transferrin, ferric citrate, IL-6, hypoxia or GDF15, revealed no differences in the activity of the HAMP promoter in the presence or absence of these polymorphisms. We conclude that c.-1010C>T and c.-582A>G polymorphisms seem to modulate iron overload development in individuals carrying the H63D mutation. However, the mechanism subjacent to this observation remains elusive.Partially funded by FCT: Programa de Financiamento Plurianual do CIGMH and SFRH/BD/60718/200

Variantes genéticas da hormona hepcidina contribuem para aumentar os níveis da ferritina sérica em indivíduos suscetíveis de desenvolverem sobrecarga em ferro

Este estudo foi parcialmente financiado pela FCT: PEst-OE/SAU/UI0009/2011

Impact of the 2009 influenza A(H1N1) pandemic wave on the pattern of hibernal respiratory virus epidemics, France, 2009.

International audienceThis short report based on clinical surveillance and laboratory data describes the circulation of rhinoviruses, influenza viruses and respiratory syncytial viruses (RSV) in France during the 2009-10 season compared with the previous winter season. The delayed circulation of RSV observed in 2009-10 compared with 2008-09 suggests that the early circulation of the 2009 pandemic influenza A(H1N1) viruses had an impact on the RSV epidemic

Proof-of-Principle That Cellular Automata Can Be Used to Predict Infestation Risk by Reticulitermes grassei (Blattodea: Isoptera)

Over the past few decades, species distribution modelling has been increasingly used to monitor invasive species. Studies herein propose to use Cellular Automata (CA), not only to model the distribution of a potentially invasive species but also to infer the potential of the method in risk prediction of Reticulitermes grassei infestation. The test area was mainland Portugal, for which an available presence-only dataset was used. This is a typical dataset type, resulting from either distribution studies or infestation reports. Subterranean termite urban distributions in Portugal from 1970 to 2001 were simulated, and the results were compared with known records from both 2001 (the publication date of the distribution models for R. grassei in Portugal) and 2020. The reported model was able to predict the widespread presence of R. grassei, showing its potential as a viable prediction tool for R. grassei infestation risk in wooden structures, providing the collection of appropriate variables. Such a robust simulation tool can prove to be highly valuable in the decision-making process concerning pest managementinfo:eu-repo/semantics/publishedVersio