Browsing by Issue Date, starting with "2016-12"
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- Salivary gland hybrid tumour revisited: could they represent high-grade transformation in a low-grade neoplasm?Publication . Hellquist, Henrik; Skalova, Alena; Azadeh, BahramSalivary gland hybrid tumour, first described in 1996, is a very rare neoplasm for which exact morphological criteria have not been universally agreed upon. In contrast, the concept of high-grade transformation (HGT) in salivary neoplasms has been widely accepted during the last decade, and the number of reported cases is rapidly increasing. A review of the literature revealed 38 cases of hybrid tumour reported in 22 publications. During approximately the same time period, well over 100 cases of HGT in salivary neoplasms have been reported. There are important histological similarities between hybrid tumours and salivary tumours with HGT. In the latter, containing one tumour component of low-grade malignancy and the other of high grade, the two tumour components are not entirely separated and appear to originate in the same area. Virtually, all cases reported as hybrid tumour had no clear lines of demarcation between the two tumour types. We are inclined to suggest that most of the 38 cases of hybrid tumours described in the literature would today better be called tumour with HGT rather than hybrid tumour. The relative proportion of the two components may vary, and the high-grade component is sometimes very small, which emphasises the importance of very generous sampling of the surgical specimen. The molecular genetic mechanisms responsible for HGT, including what used to be called hybrid tumour, remain largely unknown. Abnormalities of a few genes (including p53, C-MYC, cyclin D1, HER-2/neu) have been documented. As insufficient data exist on gene abnormalities in these lesions, conclusions as to whether or not they have a common origin and which mechanisms are involved in transformation cannot be drawn. Due to the small number of cases reported, many of which lack follow-up details; indicators of prognosis of hybrid tumours are not available, but their behaviour seems to be similar to that of tumours with HGT, i.e. an accelerated aggressive course. HGT of salivary gland neoplasms greatly influences macroscopic and microscopic evaluation of the specimen but also, given the high incidence of metastases and morbidity, carries significant treatment implications.
- Having a BLAST: searchable transcriptome resources for the gilthead sea bream and the European sea bassPublication . Louro, Bruno; Marques, João Pedro; Power, Deborah; Canário, Adelino V. M.The gilthead sea bream (Sparus aurata) and the European sea bass (Dicentrarchus labrax) are the most important aquaculture species in the Mediterranean Sea and since the last decade it has been seen an exponential increase in their available molecular resources. In order to improve accessibility to transcriptome resources, Expressed Sequence Tags (ESTs), mRNA sequences and raw read sequences were assembled and deposited in BLAST queryable databases. The publicly available sea bream and sea bass sequences (6.4 and 247.5 million) generated 45,094 and 68,117 assembled sequences, with, respectively, arithmetic mean size of 998 and 2125 bp and N50 of 1302 and 2966 bp. The assemblies will be regularly updated and new analytical tools added to the web server at http://sea.ccmar.ualg.pt. (C) 2016 Elsevier B.V. All rights reserved.
- Comment on 'Island biogeography: patterns of marine shallow-water organisms' by Hachich et al., Journal of Biogeography (2015)Publication . Ávila, Sérgio P.; Cordeiro, Ricardo; Haroun, Ricardo; Wirtz, PeterIn a recent article, Hachich et al. ( 2015, Journal of Biogeography, 42, 1871-1882) studied the large-scale biogeographical patterns of the species-area, species-island age and species-isolation relationships associated with marine shallow-water groups ( reef fish, gastropods and seaweeds) from 11 Atlantic archipelagos. We here express our concerns regarding the data accuracy used to compute the different models that tested the null hypothesis of species richness being independent of the selected variables. In our commentary, we focus mainly on the use of out-of-date checklists of gastropod and seaweed species from different archipelagos, but we also point out inaccuracies in some island age estimates and explain our disagreement with the use of the 200 m depth limit for the shallow-water gastropods and seaweeds.
- Políticas de gestão e organização educativa: os contratos de autonomia das escolas portuguesasPublication . Gregório, Maria Helena SantosEsta investigação desenvolveu-se com o propósito de compreender as políticas de gestão e organização educativa, emergentes da modalidade dos contratos de autonomia das escolas. Para tal, propusemo-nos analisar e compreender o modo como o contrato de autonomia determina ou influencía a gestão das organizações escolares. Nas últimas décadas, as organizações educativas, a descentralização e a autonomia têm recebido bastantes desenvolvimentos ao nível do estudo teórico e ao nível da implementação prática. As diversas políticas educativas, apresentadas pelo Legislador, têm sido alvo de debates densos e alargados a todos os quadrantes da vida social, tal como os aspetos que se prendem com a contratualização aplicada ao contexto educativo. Seguimos a metodologia de investigação qualitativa e optámos pelo estudo de casos múltiplos, na região algarvia. Para a análise dos dados recolhidos junto de gestões escolares, utilizámos a análise de conteúdo, realizada através de um programa informático de análise qualitativa. Nos resultados apurados, encontramos indicadores referentes a descrições sobre o modo como se vivencía, o dia a dia das escolas e os processos de gestão. Estes não se referem apenas ao contratualizado e ao modo como as escolas tiveram que criar condições para a sua aplicação, mas também a dimensões de ação e de intervenção emergentes desta contratualização, em vários âmbitos e extensões do desenvolvimento organizacional e profissional. Destacam-se aspetos relacionados com a prestação de um serviço educativo com mais sucesso e ainda aspetos que se prendem com a adequação de procedimentos de autoavaliação mais eficazes, com vista a obtenção de melhores resultados dos alunos.
- Editorial: ECAB focus issue: Engineered catalysts, robust, cost-effective and integrated bioprocesses and high-throughput screeningPublication . Aires-Barros, Raquel; Buechs, Jochen; Ferreira, GuilhermeHow can technology and industrial biotechnology contribute to a more bio-based economy? At the 3rd European Congress of Applied Biotechnology (ECAB3) in Nice in 2015, relevant topics and technologies and their contribution to sustainability were presented and discussed. In this issue of Biotechnology Journal, five special articles are selected from this conference, highlighting processes and technologies envisaging the development of engineered catalysts, robust bioprocesses, as well as high-throughput screening methods for process development.
- Gaucher disease and Lupus: a rare association?Publication . Jerónimo, Teresa; Cabrita, Ana; Pimentel, Ana; Vidinha, Joana; Fragoso, Andre; Santos, Viriato; Bernardo, Idalecio; Viana, Helena; Carvalho, Fernanda; Brito, Helena; Lazaro, Mario; Neves, Pedro LeaoGaucher disease (GD), is an autosomal recessive lysosomal storage disease that is due to mutations in the glucocerebrosidase (GC) gene, with a prevalence of 1/57,000 to 1/75,000 births worldwide and significantly more common among the Ashkenazi Jewish heritage. GD is categorized into three clinical types4 and the clinical manifestations result from the accumulation of the lipid-laden macrophages in the spleen, liver, bone, bone marrow, leading to impairment of central nervous system in the most severe cases.
- Dynamic aggregation and scheduling in CoAP/Observe-based wireless sensor networksPublication . Correia, Noélia; Sacramento, David; Schutz, G.Wireless sensor networks (WSNs) are starting to have a high impact on our societies and, for next generation WSNs to become more integrated with the Internet, researchers recently proposed to embed IPv6 into such very constrained networks. Also, constraint application protocol (CoAP) and Observe have been proposed for RESTful services to be provided. CoAP/Observe supports the use of caches/proxies and, for this reason, an observation request may resort to multiple client/server registration steps in order to get notifications. Here, we propose to plan the multiple registration steps, at proxies, of multiple observation requests in order to make proper aggregation/scheduling of notifications for transmission. This leads to less energy consumption and to an effective use of bandwidth, avoiding energy depletion of nodes, and increasing the network lifetime. Besides, mathematically formalizing the problem, a heuristic approach is developed and a discussion on how to incorporate algorithm's decision into the network is done. The proposed framework can be applied to multiple application domains (e.g., monitoring, machine to machine).
- Photochemistry of 1-and 2-Methyl-5-aminotetrazoles: structural effects on reaction pathwaysPublication . Ismael, Amin; Fausto, R.; Cristiano, Maria Lurdes SantosThe influence of the position of the methyl substituent in 1- and 2-methyl-substituted 5-aminotetrazoles on the photochemistry of these molecules is evaluated. The two compounds were isolated in an argon matrix (15 K) and the matrix was subjected to in situ narrowband UV excitation at different wavelengths, which induce selectively photochemical transformations of different species (reactants and initially formed photoproducts). The progress of the reactions was followed by infrared spectroscopy, supported by quantum chemical calculations. It is shown that the photochemistries of the two isomers, 1-methyl-(1H)-tetrazole-5-amine (la) and 2-methyl-(2H)-tetrazole-5-amine (1b), although resulting in a common intermediate diazirine 3, which undergoes subsequent photoconversion into 1-amino-3-methylcarbodiimide (H2N-N=C=N-CH3), show marked differences: formation of the amino cyanamide 4 (H2N-N(CH3)-CE equivalent to N) is only observed from the photo cleavage of the isomer la, whereas formation of the nitrile imine 2 (H2N-C-=N+=N-CH3) is only obtained from photolysis of 1b. The exclusive formation of nitrile imine from the isomer lb points to the possibility that only the 2H-tetrazoles forms can give a direct access to nitrile imines, while observation of the amino cyanamide 4 represents a novel reaction pathway in the photochemistry of tetrazoles and seems to be characteristic of 1H-tetrazoles. The structural and vibrational characterization of both reactants and photoproducts has been undertaken.
- Global sharing, local innovation: Four schools, four countries, one curriculumPublication . Castelo-Branco, Luís; Finucane, Paul; Marvão, Pedro; McCrorie, Peter; Ponte, José; Worley, PaulBackground: Many internal and external obstacles, must be overcome when establishing a new medical school, or when radically revising an existing medical curriculum.Aims: Twenty-five years after the Flinders University curriculum was introduced as the first graduate-entry medical programme (GEMP) in Australia, we aim at describing how it has been adopted and adapted by several other schools, in Australia and in Europe (UK, Ireland, and Portugal).Method/Results: This paper reports on the experience of four schools establishing a new medical school or new curriculum at different times and in different settings.Conclusions: We believe that these experiences might be of interest to others contemplating a similar development.
- Genetic implications of phylogeographical patterns in the conservation of the boreal wetland butterfly Colias palaeno (Pieridae)Publication . Kramp, Katja; Cizek, Oldrich; Madeira, Pedro M.; Ramos, Ana; Konvicka, Martin; Castilho, Rita; Schmitt, ThomasThe boreo-montane wetland butterfly species Colias palaeno has a European distribution from the Alps to northern Fennoscandia. Within its European range, the species' populations have shrunk dramatically in recent historical times. Therefore, detailed baseline knowledge of the genetic makeup of the species is pivotal in planning potential conservation strategies. We collected 523 individuals from 21 populations across the entire European range and analyzed nuclear (20 allozyme loci) and mitochondrial (600bp of the cytochrome c oxidase subunit I gene) genetic markers. The markers revealed contrasting levels of genetic diversity and divergence: higher in allozymes and lower in mitochondrial sequences. Five main groups were identified by allozymes: Alps, two Czech groups, Baltic countries, Fennoscandia, and Poland. The haplotype mitochondrial network indicates a recent range expansion. The most parsimonious interpretation for our results is the existence of a continuous Wurm glacial distribution in Central Europe, with secondary disjunction during the Last Glacial Maximum into a south-western and a north-eastern fragment and subsequent moderate differentiation. Both groups present signs of postglacial intermixing in the Czech Republic. However, even a complete extinction in this region would not considerably affect the species' genetic basis, as long as the source populations in the Alps and in northern Europe, comprising the most relevant evolutionary units for conservation, are surviving.