Nanostructured natural-based polyelectrolyte multilayers to agglomerate chitosan particles into scaffolds for tissue engineering

The Layer-by-Layer (LbL) deposition technique is a self-assembly process that allows the coating of material's surface with nanostructured layers of polyelectrolytes, allowing to control several surface properties. This technique presents some advantages when compared with other thin film assembly techniques like having the possibility to coat surfaces with complex geometries in mild conditions or to incorporate active compounds. Tissue engineering involves typically the use of porous biodegradable scaffolds for the temporary support of cells. Such structures can be produced by agglomeration of micro-spheres that needs to be fixed into a three dimensional structure. In this work we suggest the use of LbL to promote such mechanical fixation in free-formed micro-spheres assemblies and simultaneously to control the properties of its surface. For the proof of concept the biological performance of chitosan/alginate multilayers is first investigated in two-dimensional models in which the attachment and proliferation of L929 and ATDC5 cells are studied in function of the number of layers and the nature of the final layer. Scaffolds prepared by agglomeration of chitosan particles using the same multilayered system were processed and characterized; it was found that they could support the attachment and proliferation of ATDC5 cells. This study suggests that LbL can be used as a versatile methodology to prepare scaffolds by particle agglomeration that could be suitable for tissue engineering applications.Fundo Europeu de Desenvolvimento Regional (FEDER) através do Programa Operacional de Cooperação Transfronteiriça Espanha Portugal 2007-2013 (POCTEP)Fundação para a Ciência e a Tecnologia (FCT

AGREGADOS TUBULARES DE RETÍCULO ENDOPLASMÁTICO LISO EM OVÓCITOS HUMANOS E SUA INFLUÊNCIA NAS TAXAS DE FERTILIZAÇÃO E GRAVIDEZ

O impacto da presença de anomalias morfológicas ovocitárias na fertilização e taxas de gravidez é um tema controverso na literatura. A presença de agregados tubulares de retículo endoplasmático liso (AT-REL) foi associada a taxas de gravidez mais baixas e a maior incidência de complicações obstétricas. A estrutura ultramiscroscópica destes AT-REL não está descrita. Este trabalho teve como objectivos: a) determinar a influência da presença de AT-REL nas taxas de fertilização e gravidez; b) descrever a ultrastrutura dos AT-REL de ovócitos humanos maduro

Pragas quarentenárias que ameaçam a cultura da mangueira no Brasil.

Define-se como praga quarentenária todo organismo de natureza animal e/ou vegetal que, estando presente em outros países ou regiões, mesmo sob controle permanente, constitua ameaça à economia agrícola do país ou região importadora. Tais organismos são, geralmente, exóticos para esse país ou região e podem ser disseminados, entre outros meios, pelo trânsito de plantas, animais ou por frutos e sementes infestadas, isto é, podem ser transportados de um local para outro auxiliado pelo homem e seus meios de transporte e comércio. As pragas quarentenárias se agrupam nas seguintes categorias: A1- Pragas exóticas não presentes e A2- Pragas de importância econômica potencial, já presentes no país, porém apresentando disseminação localizada e submetidas a programa oficial de controle.bitstream/CPAF-AP-2009-09/14351/1/CTE87.pd

Consensus Recommendations of the Multiple Sclerosis Study Group and Portuguese Neuroradiological Society for the Use of the Magnetic Resonance Imaging in Multiple Sclerosis in Clinical Practice: Part 1

INTRODUCTION: Magnetic resonance imaging is established as a recognizable tool in the diagnosis and monitoring of multiple sclerosis patients. In the present, among multiple sclerosis centers, there are different magnetic resonance imaging sequences and protocols used to study multiple sclerosis that may hamper the optimal use of magnetic resonance imaging in multiple sclerosis. In this context, the Group of Studies of Multiple Sclerosis and the Portuguese Society of Neuroradiology, after a joint discussion, appointed a committee of experts to create recommendations adapted to the national reality on the use of magnetic resonance imaging in multiple sclerosis. The purpose of this document is to publish the first Portuguese consensus recommendations on the use of magnetic resonance imaging in multiple sclerosis in clinical practice. MATERIAL AND METHODS: The Group of Studies of Multiple Sclerosis and the Portuguese Society of Neuroradiology, after discussion of the topic in national meetings and after a working group meeting held in Figueira da Foz on May 2017, have appointed a committee of experts that have developed by consensus several standard protocols on the use of magnetic resonance imaging in the diagnosis and follow-up of multiple sclerosis. The document obtained was based on the best scientific evidence and expert opinion. Subsequently, the majority of Portuguese multiple sclerosis consultants and departments of neuroradiology scrutinized and reviewed the consensus paper; comments and suggestions were considered. Technical magnetic resonance imaging protocols regarding diagnostic, monitoring and the recommended information to be included in the magnetic resonance imaging report will be published in a separate paper. RESULTS: We provide some practical guidelines to promote standardized strategies to be applied in the clinical practice setting of Portuguese healthcare professionals regarding the use of magnetic resonance imaging in multiple sclerosis. CONCLUSION: We hope that these first Portuguese magnetic resonance imaging guidelines, based in the best available clinical evidence and practices, will serve to optimize multiple sclerosis management and improve multiple sclerosis patient care across Portugal.info:eu-repo/semantics/publishedVersio

Multiple Sclerosis Patient Management During the COVID-19 Pandemic: Practical Recommendations From the Portuguese Multiple Sclerosis Study Group (GEEM)

The spread of the COVID-19 pandemic has imposed significant challenges on healthcare provision, requiring changes in the conventional patient management, particularly in chronic diseases like multiple sclerosis (MS). To increase patient safety and reduce the risk of infection, while ensuring an appropriate and regular follow-up, tele-medicine gained prominence as a valid alternative to face-to-face appointments. However, the urgency of the implementation and the lack of experience in most MS centers led to "ad hoc" and extremely diverse approaches, which now merit to be standardized and refined. Indeed, while tele-consultation cannot fully replace face-to-face visits, it certainly can, and will, be incorporated as part of the routine care of MS patients in the near future. Bearing this in mind, the Portuguese Multiple Sclerosis Study Group (GEEM) has developed a set of recommendations for the usage of tele-medicine in the management of MS patients, both during the pandemic and in the future. The consensus was obtained through a two-step modified Delphi methodology, resulting in 15 recommendations, which are detailed in the manuscript.info:eu-repo/semantics/publishedVersio

Genomic analysis of four strains of Corynebacterium pseudotuberculosis bv. Equi isolated from horses showing distinct signs of infection.

The genomes of four strains (MB11, MB14, MB30, and MB66) of the species Corynebacterium pseudotuberculosis biovar equi were sequenced on the Ion Torrent PGM platform, completely assembled, and their gene content and structure were analyzed. The strains were isolated from horses with distinct signs of infection, including ulcerative lymphangitis, external abscesses on the chest, or internal abscesses on the liver, kidneys, and lungs. The average size of the genomes was 2.3 Mbp, with 2169 (Strain MB11) to 2235 (Strain MB14) predicted coding sequences (CDSs). An optical map of the MB11 strain generated using the KpnI restriction enzyme showed that the approach used to assemble the genome was satisfactory, producing good alignment between the sequence observed in vitro and that obtained in silico. In the resulting Neighbor-Joining dendrogram, the C. pseudotuberculosis strains sequenced in this study were clustered into a single clade supported by a high bootstrap value. The structural analysis showed that the genomes of the MB11 and MB14 strains were very similar, while the MB30 and MB66 strains had several inverted regions. The observed genomic characteristics were similar to those described for other strains of the same species, despite the number of inversions found. These genomes will serve as a basis for determining the relationship between the genotype of the pathogen and the type of infection that it causes

Por uma nova cultura da água no ensino básico

A presente comunicação centra-se na apresentação à comunidade científica de um Projecto de investigação em Educação que tem como finalidade produzir contributos para o Ensino Básico, no âmbito do que se designa como uma Nova Cultura da Água. Com esta iniciativa pretendemos não só alertar para a pertinência e importância de estudos em ordem a uma temática cada vez mais emergente, mas também recolher contributos significativos de uma comunidade mais alargada. O referido projecto centra-se pois no bem Água. Começará por procurar conhecer melhor como ele é evocado e tratado no Ensino Básico. Destina-se a aprofundar e promover teorias, conhecimentos, competências, valores, atitudes e práticas que potenciem o bom uso e a protecção daquele bem, e de um modo mais geral uma alteração de posturas culturais e mesmo civilizacionais. Fá-lo-á segundo perspectivas científicas, pedagógicas, didácticas e sociais em parte já construídas e em parte a construir, e que justificadamente se considerem adequadas. O Projecto assume estar à partida marcado por saberes, perspectivas, ideais, dilemas e objectivos dos elementos da equipa do Projecto e por outras visões que, globalmente e de um modo aproximativo, aglomeramos sob a designação Nova Cultura da Água. Simultaneamente, assume que pretende contribuir para que tal Nova Cultura da Água seja mais bem compreendida e especificada, e em particular para que ela seja mais enriquecida com contributos portugueses. O âmbito central de intervenção do Projecto é o Ensino Básico, mas desde logo isso implica a sua intersecção com a Formação (Inicial e Contínua) de Professores, e portanto com o Ensino Superior. Além disso, pela natureza do tema, do bem, em estudo, o Projecto intersecta-se também com os mundos das Ciências e das Tecnologias. Intersecta-se também com a Sociedade em geral, e designadamente com a formação para a cidadania de cidadão portugueses que são também cidadãos da Península Ibérica, da Europa e do Mundo. O Projecto terá pois múltiplas incidências e mesmo, previsivelmente, contributos de vários tipos e âmbitos, designadamente a nível de divulgação científica e a um nível pedagógico geral. Mas é essencialmente um Projecto do âmbito da Didáctica. Tem a sua focagem na Escola, portanto em ambientes de ensino e aprendizagem formais, e incide sobre meios e métodos relacionados com ambientes de aula (em sentido lato)