Toxoplasma gondii: serological study in pigs slaughtered in Portugal

Toxoplasma gondii has a worldwide distribution and usually is not detected macroscopically by traditional meat inspection methods. The aim of this study was to assess the seroprevalence of Toxoplasma gondii in slaughter swine using a modified direct agglutination method (MAT) (Toxo-Screen DA, Biomérieux® SA). No positive results were obtained in sera from 337 animals from 12 intensive production farms tested in duplicate at the dilutions of 1:20 and 1:40. The estimated seroprevalence was 0%. The 95% confidence intervals ranged from 0 to 21.8% within batches, and 0 to 1.1% of all animals. In 10 of the 12 farms, Toxoplasma seroprevalence was below 7% (\u3e99% confidence level). In the remaining two farms, the sampling fraction was too small to distinguish a population with prevalence of 7% from a disease-free population. Our findings suggest that Toxoplasma seroprevalence in intensive pig farms is likely to be below 7%. However, selection of farms was not random, so further studies are required to allow making inferences for all intensive pig farms in the centre and north of Portugal

Isolation of adipose stem cells (ASCs) subpopulations with distinct differentiation potential

[Excerpt] ASCs are becoming the elected cells for TE applications because ASCs have been easily isolated and have shown good differentiation potential. The aim of this work was to isolate the ASCs using immunomagnetic beads coated with different antibodies (Ab) markers and to test the differentiation potential of the different subpopulations isolated. [...]Marie Curie Actions Alea Jacta Est, Project HIPPOCRATES, NoE EXPERTISSUESinfo:eu-repo/semantics/publishedVersio

Development of micro-patterned surfaces of poly(butylene succinate) by micromolding for guided tissue engineering

Native tissues present complex architectures at the micro- and nanoscale that dictate their biological function. Several microfabrication techniques have been employed for engineering polymeric surfaces that could replicate in vitro these micro- and nanofeatures. In this study, biomimetic surfaces of poly(butylene succinate) (PBS) were engineered by a micromolding technique. After the optimization of the system parameters, 20 surfaces with different combinations of groove and ridge sizes were developed and characterized by scanning electron microscopy (SEM). The influence of the engineered microfeatures over the viability and attachment of human adipose derived adult stem cells (hASCs) was evaluated. hASCs cultured onto the engineered surfaces were demonstrated to remain viable for all tested patterns. SEM and immunostaining showed adequate attachment and spreading of the stem cells for all the patterned groove/ridge combinations. This study indicated that it is possible to engineer micropatterned surfaces of PBS and that the developed structures could have great potential for tissue engineering where cell alignment is an essential requisite.Fundação para a Ciência e a Tecnologia (FCT)MIT-Portugal ProgramNoE EXPERTISSUES (NMP3-CT-2004-500283

Castanha na roça: sinergia entre agricultura e extrativismo em uma unidade de conservação de uso sustentável - RESEX Cajari.

Este trabalho busca evidenciar a sinergia entre agricultura e extrativismo, demonstrando que existe um potencial produtivo de castanha da amazônia em áreas de roças e capoeiras provenientes da agricultura itinerante, que podem ser conduzidas como sistemas agroflorestais (SAFs). A partir do levantamento realizado em 14 comunidades da RESEX, foram inventariadas 90 áreas provenientes da agricultura com diferentes períodos de pousio. Dessas, 42 são capoeiras "abandonadas" e 48 são áreas que foram selecionadas, em 2012, para a agricultura. Nessas áreas foram encontradas 1.445 castanheiras (cast), a maior parte jovens, gerando uma densidade aproximada de 13 cast ha-1. A densidade nas capoeiras abandonadas foi de 17 cast ha-1 e nas capoeiras em cultivo foi de 8 cast ha1, confirmando que os castanheiros optam por colocar a roça em áreas com menor regeneração de castanheiras. Do total de castanheiras inventariadas, 7,4% são comprovadamente produtivas e muitas ainda não produzem frutos, mas já apresentam floração. Em algumas dessas áreas de capoeiras, os castanheiros já fazem a coleta dos ouriços. A interação, bem como a troca de conhecimento com os agroextrativistas, proporcionou uma compreensão melhor da realidade local e facilitou a realização do trabalho. A maior densidade de regenerações de castanheiras e maior crescimento nas áreas usadas para agricultura itinerante, do que dentro na floresta madura, justifica o manejo dessas áreas como se fossem SAFs, com a manutenção das castanheiras jovens no meio do roçado para formação de futuros castanhais

A novel bioreactor design for enhanced stem cells proliferation and differentiation in tissue engineered constructs

[Excerpt] Recent studies have shown that culturing undifferentiated stem cells in appropriate biochemical environments and under mechanical stimulation could provide the correct signals for cellular proliferation, differentiation and subsequent extracellular matrix production. This triggered a growing interest about in vitro biomechanically-stimulating culture environments. [...]info:eu-repo/semantics/publishedVersio

Molecularly imprinted intelligent scaffolds for tissue engineering applications

The development of molecularly imprinted polymers (MIPs) using biocompatible production methods enables the possibility to further exploit this technology for biomedical applications. Tissue engineering (TE) approaches use the knowledge of the wound healing process to design scaffolds capable of modulating cell behavior and promote tissue regeneration. Biomacromolecules bear great interest for TE, together with the established recognition of the extracellular matrix, as an important source of signals to cells, both promoting cellâ cell and cellâ matrix interactions during the healing process. This review focuses on exploring the potential of protein molecular imprinting to create bioactive scaffolds with molecular recognition for TE applications based on the most recent approaches in the field of molecular imprinting of macromolecules. Considerations regarding essential components of molecular imprinting technology will be addressed for TE purposes. Molecular imprinting of biocompatible hydrogels, namely based on natural polymers, is also reviewed here. Hydrogel scaffolds with molecular memory show great promise for regenerative therapies. The first molecular imprinting studies analyzing cell adhesion report promising results with potential applications for cell culture systems, or biomaterials for implantation with the capability for cell recruitment by selectively adsorbing desired molecules.The authors wish to thank Dr. Julia Vela-Ramirez, Ms. Heidi Culver, and Mr. John Clegg for important discussions and suggestions. This work was supported in part by the University of Texas-Portugal Collaborative Research Program, and the Grant UTAP-ICDT/CTM-BIO/0023/2014. M.E.W. is supported by a National Science Foundation Graduate Research Fellowship

Buckling length of a steel column for fire design

The Eurocode 3 part 1-2 gives some simple rules to determine the buckling length lfi of a steel column for fire design. In the case of a braced frame in which each storey comprises a separate fire compartment with sufficient fire resistance, Eurocode 3 suggests that the buckling length may be taken as lfi=0.5L in an intermediate storey and as lfi=0.7L in the top storey, where L is the system length in the relevant storey.http://www.sciencedirect.com/science/article/B6V2Y-4MYMP09-1/1/a7f3181ad12d91b9f77b14c13ecb449

Development of new chitosan/carrageenan nanoparticles for drug delivery applications

The use of polymeric nanoparticles, especially those composed of natural polymers, has become a very interesting approach in drug delivery., mainly because of the advantages offered by their small dimensions. The aim of this work was to develop a novel formulation of nanoparticles comprised of two natural marine-derived polymers, namely chitosan and carrageenan, and to evaluate their potential for the association and controlled release of macromolecules. Nanoparticles were obtained in a hydrophilic environment, under very mild conditions, avoiding the use of organic solvents or other aggressive technologies for their preparation. The developed nanocarriers presented sizes within 350-650 run and positive zeta potentials of 50-60 mV. Polymeric interactions between nanoparticles' components were evaluated by Fourier transform infrared spectroscopy. Using ovalbumin as model protein, nanoparticles evidenced loading capacity varying from 4% to 17%, and demonstrated excellent capacity to provide a controlled release for up to 3 weeks. Furthermore, nanoparticles have demonstrated to exhibit a noncytotoxic behavior in biological in vitro tests performed using L929 fibroblasts, which is critical regarding the biocompatibility of those carriers. In summary, the developed chitosan-carrageenan nanoparticles have shown promising properties to be used as carriers of therapeutic macromolecules, with potential application not only strictly in drug delivery, but also in broader areas, such as tissue engineering and regenerative medicine. (C) 2009 Wiley Periodicals, Inc. J Biomed Mater Res 92A: 1265-1272, 2010Contract grant sponsor: Portuguese Foundation for Science and Technology (FCT) (POCTI/FEDER programmes)Contract grant sponsor: European Union STREP Project HIPPOCRATES; contract grant number: NMP3-CT-2003505758Contract grant sponsor: European NoE EXPERTISSUES; contract grant number: NMP3-CT-2004-50028

Modified Gravity on the Brane and Dark Energy

We analyze the dynamics of an AdS5 braneworld with matter fields when gravity is allowed to deviate from the Einstein form on the brane. We consider exact 5-dimensional warped solutions which are associated with conformal bulk fields of weight -4 and describe on the brane the following three dynamics: those of inhomogeneous dust, of generalized dark radiation, and of homogeneous polytropic dark energy. We show that, with modified gravity on the brane, the existence of such dynamical geometries requires the presence of non-conformal matter fields confined to the brane.Comment: Revised version published in Gen. Rel. Grav. Typos corrected, updated reference and some remarks added for clarity. 11 pages, latex, no figure