368 research outputs found
Meta-analysis of trials comparing anastrozole and tamoxifen for adjuvant treatment of postmenopausal women with early breast cancer
<p>Abstract</p> <p>Objective</p> <p>It was aimed to review the literature and make a meta-analysis of the trials on both upfront, switching, and sequencing anastrozole in the adjuvant treatment of early breast cancer.</p> <p>Methods</p> <p>The PubMed, ClinicalTrials.gov and Cochrane databases were systematically reviewed for randomized-controlled trials comparing anastrozole with tamoxifen in the adjuvant treatment of early breast cancer.</p> <p>Results</p> <p>The combined hazard rate of 4 trials for event-free survival (EFS) was 0.77 (95%CI: 0.70â0.85) (<it>P </it>< 0.0001) for patients treated with anastrozole compared with tamoxifen. In the second analysis in which only ITA, ABCSG 8, and ARNO 95 trials were included and ATAC (upfront trial) was excluded, combined hazard rate for EFS was 0.64 (95%CI: 0.52â0.79) (<it>P </it>< 0.0001). In the third analysis including hazard rate for recurrence-free survival (excluding non-disease related deaths) of estrogen receptor-positive patients for ATAC trial and hazard rate for EFS of all patients for the rest of the trials, combined hazard rate was 0.73 (95%CI: 0.65â0.81) (<it>P </it>< 0.0001).</p> <p>Conclusion</p> <p>Anastrozole appears to have superior efficacy than tamoxifen in the adjuvant hormonal treatment of early breast cancer. Until further clinical evidence comes up, aromatase inhibitors should be the initial hormonal therapy in postmenopausal early breast cancer patients and switching should only be considered for patients who are currently receiving tamoxifen.</p
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
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
Review of natural fibre-reinforced hybrid composites
Natural fibre-reinforced hybrid composites which contain one or more types of natural reinforcement are gaining increasing research interest. This paper presents a review of natural fibre-reinforced hybrid composites. Both thermoplastic and thermoset composites reinforced by hybrid/synthetic fibres or hybrid/hybrid fibres are reviewed. The properties of natural fibres, the properties and processing of composites are summarised
Thermal properties comparison of hybrid CF/FF and BF/FF cyanate ester-based composites
[EN] Insights within thermal expansion, conductivity, and decomposition dependencies with temperature on symmetrical and
unsymmetrical layered carbon (CF) or basalt (BF) fabrics in combination with flax fibers (FF) were approached. Driven by
commercial application and environmental concerns, the paper draws attention on a modified formula of cyanate ester with
a common epoxy resin under an optimized ratio of 70:30 (vol%) as well as on the hybrid reinforcements stacking
sequences. Synergetic effects were debated in terms of the CF and BF stacking sequences and corresponding volume
fraction followed by comparisons with values predicted by the deployment of hybrid mixtures rules (RoHM/iRoHM). CF
hybrid architectures revealed enhanced effective thermophysical properties over their BF counterparts and both over the
FF-reinforced polymer composite considered as a reference. Thermal conductivities spread between 0.116 and
0.299 W m-1 K-1 from room temperature up to 250 C on all hybrid specimens, giving rise to an insulator character.
Concerning the coefficient of thermal expansion, CF hybrid architectures disclosed values of 1.236 10-6 K-1 and
3.102 10-6 K-1 compared with BF affine exhibiting 4.794 10-6 K-1 and 6.245 10-6 K-1, respectively, with an increase
in their volume fraction.The corresponding author gratefully acknowledges the financial assistance of German Academic Exchange Service-DAAD that enabled and supported the internship with Fraunhofer Research Institution for Polymeric Materials and Composites-PYCO, Germany. Many thanks go to Dr. Christian Dreyer and Dr. Maciej Gwiazda for the resin formula and access to the composite manufacturing technology.Motoc, DL.; FerrĂĄndiz Bou, S.; Balart, R. (2018). Thermal properties comparison of hybrid CF/FF and BF/FF cyanate ester-based composites. Journal of Thermal Analysis and Calorimetry. 133(1):509-518. https://doi.org/10.1007/s10973-018-7222-yS5095181331Assarar M, Zouari W, Sabhi H, Ayad R, Berthelot J-M. Evaluation of the damping of hybrid carbonâflax reinforced composites. Compos Struct. 2015;132:148â54.Duc F, Bourban PE, Plummer CJG, MĂ„nson JAE. Damping of thermoset and thermoplastic flax fibre composites. Compos A Appl Sci Manuf. 2014;64:115â23.Saba N, Jawaid M, Alothman OY, Paridah MT. A review on dynamic mechanical properties of natural fibre reinforced polymer composites. Constr Build Mater. 2016;106:149â59.Tian H, Zhang S, Ge X, Xiang A. Crystallization behaviors and mechanical properties of carbon fiber-reinforced polypropylene composites. J Therm Anal Calorim. 2017;128(3):1495â504.Alvarez V, Rodriguez E, VĂĄzquez A. Thermaldegradation and decomposition of jute/vinylester composites. J Therm Anal Calorim. 2006;85(2):383â9.Manfredi LB, RodrĂguez ES, Wladyka-Przybylak M, VĂĄzquez A. Thermal degradation and fire resistance of unsaturated polyester, modified acrylic resins and their composites with natural fibres. Polym Degrad Stab. 2006;91(2):255â61.Lazko J, Landercy N, Laoutid F, Dangreau L, Huguet MH, Talon O. Flame retardant treatments of insulating agro-materials from flax short fibres. Polym Degrad Stab. 2013;98(5):1043â51.Bar M, Alagirusamy R, Das A. Flame retardant polymer composites. Fibers Polym. 2015;16(4):705â17.Kollia E, Loutas T, Fiamegkou E, Vavouliotis A, Kostopoulos V. Degradation behavior of glass fiber reinforced cyanate ester composites under hydrothermal ageing. Polym Degrad Stab. 2015;121:200â7.Jawaid M, Abdul Khalil HPS. Cellulosic/synthetic fibre reinforced polymer hybrid composites: a review. Carbohyd Polym. 2011;86(1):1â18.Azwa ZN, Yousif BF, Manalo AC, Karunasena W. A review on the degradability of polymeric composites based on natural fibres. Mater Des. 2013;47:424â42.H-y Cheung, M-p Ho, K-t Lau, Cardona F, Hui D. Natural fibre-reinforced composites for bioengineering and environmental engineering applications. Compos B Eng. 2009;40(7):655â63.Dittenber DB, GangaRao HVS. Critical review of recent publications on use of natural composites in infrastructure. Compos A Appl Sci Manuf. 2012;43(8):1419â29.Faruk O, Bledzki AK, Fink H-P, Sain M. Biocomposites reinforced with natural fibers: 2000â2010. Prog Polym Sci. 2012;37(11):1552â96.Praveen RS, Jacob S, Murthy CRL, Balachandran P, Rao YVKS. Hybridization of carbonâglass epoxy composites: an approach to achieve low coefficient of thermal expansion at cryogenic temperatures. Cryogenics. 2011;51(2):95â104.Jawaid M, Abdul Khalil HPS, Alattas OS. Woven hybrid biocomposites: dynamic mechanical and thermal properties. Compos A Appl Sci Manuf. 2012;43(2):288â93.Swolfs Y, Gorbatikh L, Verpoest I. Fibre hybridisation in polymer composites: a review. Compos A Appl Sci Manuf. 2014;67:181â200.Rojo E, Alonso MV, Oliet M, Del Saz-Orozco B, Rodriguez F. Effect of fiber loading on the properties of treated cellulose fiber-reinforced phenolic composites. Compos B Eng. 2015;68:185â92.LeGault M. Natural fiber composites: market share, one part at the time. Compos World. 2016;5(2):68â75.Joshi SV, Drzal LT, Mohanty AK, Arora S. Are natural fiber composites environmentally superior to glass fiber reinforced composites? Compos A Appl Sci Manuf. 2004;35(3):371â6.Wambua P, Ivens J, Verpoest I. Natural fibres: can they replace glass in fibre reinforced plastics? Compos Sci Technol. 2003;63(9):1259â64.Bertomeu D, GarcĂa-Sanoguera D, Fenollar O, Boronat T, Balart R. Use of eco-friendly epoxy resins from renewable resources as potential substitutes of petrochemical epoxy resins for ambient cured composites with flax reinforcements. Polym Compos. 2012;33(5):683â92.Alam M, Akram D, Sharmin E, Zafar F, Ahmad S. Vegetable oil based eco-friendly coating materials: a review article. Arab J Chem. 2014;7(4):469â79.Bakare FO, Ramamoorthy SK, Ă
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Results of an international phosphorus digestibility ring test with broiler chickens
The objective of this ring test was to investigate the prececal phosphorus (P) digestibility of soybean meal (SBM) in broiler chickens using the trial protocol proposed by the World's Poultry Science Association. It was hypothesized that prececal P digestibility of SBM determined in the collaborating stations is similar. Three diets with different inclusion levels of SBM were mixed in a feed mill specialized in experimental diets and transported to 17 collaborating stations. Broiler chicks were raised on commercial starter diets according to station-specific management routine. Then they were fed the experimental diets for a minimum of 5 d before content of the posterior half of the ileum was collected. A minimum of 6 experimental replicates per diet was used in each station. All diets and digesta samples were analyzed in the same laboratory. Diet, station, and their interaction significantly affected (P < 0.05) the prececal digestibility values of P and calcium of the diets. The prececal P digestibility of SBM was determined by linear regression and varied among stations from 19 to 51%, with significant differences among stations. In a subset of 4 stations, the prececal disappearance of myo-inositol 1,2,3,4,5,6-hexakis (dihydrogen phosphate)-P; InsP6-P) also was studied. The prececal InsP6-P disappearance correlated well with the prececal P digestibility. We hypothesized that factors influencing InsP6 hydrolysis were main contributors to the variation in prececal P digestibility among stations. These factors were probably related to the feeding and housing conditions (floor pens or cages) of the birds in the pre-experimental phase. Therefore, we suggest that the World's Poultry Science Association protocol for the determination of digestible P be should extended to the standardization of the pre-experimental period. We also suggest that comparisons of P digestibility measurements among studies are made only with great caution until the protocol is more refined
Transcriptional Responses of Resistant and Susceptible Fish Clones to the Bacterial Pathogen Flavobacterium psychrophilum
Flavobacterium psychrophilum is a bacterial species that represents one of the most important pathogens for aquaculture worldwide, especially for salmonids. To gain insights into the genetic basis of the natural resistance to F. psychrophilum, we selected homozygous clones of rainbow trout with contrasted susceptibility to the infection. We compared the transcriptional response to the bacteria in the pronephros of a susceptible and a resistant line by micro-array analysis five days after infection. While the basal transcriptome of healthy fish was significantly different in the resistant and susceptible lines, the transcriptome modifications induced by the bacteria involved essentially the same genes and pathways. The response to F. psychrophilum involved antimicrobial peptides, complement, and a number of enzymes and chemokines. The matrix metalloproteases mmp9 and mmp13 were among the most highly induced genes in both genetic backgrounds. Key genes of both pro- and anti-inflammatory response such as IL1 and IL10, were up-regulated with a greater magnitude in susceptible animals where the bacterial load was also much higher. While higher resistance to F. psychrophilum does not seem to be based on extensive differences in the orientation of the immune response, several genes including complement C3 showed stronger induction in the resistant fish. They may be important for the variation of susceptibility to the infection
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