Impacts of in vivo and in vitro exposures to tamoxifen: comparative effects on human cells and marine organisms

Tamoxifen (TAM) is a first generation-SERM administered for hormone receptor-positive (HER+) breast cancer in both pre- and post-menopausal patients and may undergo metabolic activation in organisms that share similar receptors and thus face comparable mechanisms of response. The present study aimed to assess whether environmental trace concentrations of TAM are bioavailable to the filter feeder M. galloprovincialis (100 ng L-1) and to the deposit feeder N. diversicolor (0.5, 10, 25 and 100 ng L-1) after 14 days of exposure. Behavioural impairment (burrowing kinetic), neurotoxicity (AChE activity), endocrine disruption by alkali-labile phosphate (ALP) content, oxidative stress (SOD, CAT, GPXs activities), biotransformation (GST activity), oxidative damage (LPO) and genotoxicity (DNA damage) were assessed. Moreover, this study also pertained to compare TAM cytotoxicity effects to mussels and targeted human (i.e. immortalized retinal pigment epithelium - RPE; and human transformed endothelial cells - HeLa) cell lines, in a range of concentrations from 0.5 ng L-1 to 50 μg L-1. In polychaetes N. diversicolor, TAM exerted remarkable oxidative stress and damage at the lowest concentration (0.5 ng L-1), whereas significant genotoxicity was reported at the highest exposure level (100 ng L-1). In mussels M. galloprovincialis, 100 ng L-1 TAM caused endocrine disruption in males, neurotoxicity, and an induction in GST activity and LPO byproducts in gills, corroborating in genotoxicity over the exposure days. Although cytotoxicity assays conducted with mussel haemocytes following in vivo exposure was not effective, in vitro exposure showed to be a feasible alternative, with comparable sensitivity to human cell line (HeLa).info:eu-repo/semantics/publishedVersio

Fundão Sénior, Território Maior: emigração, atratividade territorial e inovação social

Num território marcado pelo envelhecimento demográfico, por importantes fluxos migratórios e, ao mesmo tempo, pelo aumento e qualificação dos serviços e equipamentos sociais de apoio à 3ª idade, o Município do Fundão tem vindo a delinear estratégias que, no que diz respeito à população mais idosa, possam transformar o Fundão numa “Cidade Amiga das Pessoas Idosas”. É nessa sequência que se elabora a proposta do Projeto Fundão Sénior, Território Maior, com o intuito de promover um conjunto de respostas que potenciem a capacidade atrativa e a fixação no território por parte de um público-alvo concreto, aquele que corresponde à população sénior de naturalidade portuguesa que se encontra a residir fora do País. O projeto visa dar resposta a uma questão muito concreta: como pode o concelho do Fundão ser atrativo para os emigrantes que pretendam regressar ao seu país após a sua aposentação e ali equacionem fixar residência? O projeto baseia-se num prévio diagnóstico feito junto da comunidade portuguesa emigrante em França, maioritariamente mas não exclusivamente originária do concelho do Fundão, com idades entre os 50 e os 65 anos. Junto da mesma tentaram perceber-se quais as principais motivações para um eventual regresso a Portugal após a aposentação e sob que condições um determinado território se pode tornar atrativo como local escolhido para aí fixarem a sua nova residência. Na sequência do diagnóstico, definiram-se dois eixos estratégicos de intervenção: por um lado, criar no concelho medidas de incentivo, acompanhamento e apoio ao regresso de emigrantes reformados que, ao mesmo tempo, constituam fatores de atratividade territorial para este público-alvo; por outro, definir uma abordagem capaz de potenciar sinergias entre os agentes locais e renovar as funções sociais que os equipamentos já disponíveis podem satisfazer, numa lógica de inovação social ao nível das respostas sociais disponibilizadas, da satisfação de necessidades sociais emergentes e da promoção da qualidade de vida e bemestar.info:eu-repo/semantics/publishedVersio

Evaluation of Jackknife and Bootstrap for Defining Confidence Intervals for Pairwise Agreement Measures

Several research fields frequently deal with the analysis of diverse classification results of the same entities. This should imply an objective detection of overlaps and divergences between the formed clusters. The congruence between classifications can be quantified by clustering agreement measures, including pairwise agreement measures. Several measures have been proposed and the importance of obtaining confidence intervals for the point estimate in the comparison of these measures has been highlighted. A broad range of methods can be used for the estimation of confidence intervals. However, evidence is lacking about what are the appropriate methods for the calculation of confidence intervals for most clustering agreement measures. Here we evaluate the resampling techniques of bootstrap and jackknife for the calculation of the confidence intervals for clustering agreement measures. Contrary to what has been shown for some statistics, simulations showed that the jackknife performs better than the bootstrap at accurately estimating confidence intervals for pairwise agreement measures, especially when the agreement between partitions is low. The coverage of the jackknife confidence interval is robust to changes in cluster number and cluster size distribution

Ranked Adjusted Rand: integrating distance and partition information in a measure of clustering agreement

BACKGROUND: Biological information is commonly used to cluster or classify entities of interest such as genes, conditions, species or samples. However, different sources of data can be used to classify the same set of entities and methods allowing the comparison of the performance of two data sources or the determination of how well a given classification agrees with another are frequently needed, especially in the absence of a universally accepted "gold standard" classification. RESULTS: Here, we describe a novel measure – the Ranked Adjusted Rand (RAR) index. RAR differs from existing methods by evaluating the extent of agreement between any two groupings, taking into account the intercluster distances. This characteristic is relevant to evaluate cases of pairs of entities grouped in the same cluster by one method and separated by another. The latter method may assign them to close neighbour clusters or, on the contrary, to clusters that are far apart from each other. RAR is applicable even when intercluster distance information is absent for both or one of the groupings. In the first case, RAR is equal to its predecessor, Adjusted Rand (HA) index. Artificially designed clusterings were used to demonstrate situations in which only RAR was able to detect differences in the grouping patterns. A study with larger simulated clusterings ensured that in realistic conditions, RAR is effectively integrating distance and partition information. The new method was applied to biological examples to compare 1) two microbial typing methods, 2) two gene regulatory network distances and 3) microarray gene expression data with pathway information. In the first application, one of the methods does not provide intercluster distances while the other originated a hierarchical clustering. RAR proved to be more sensitive than HA in the choice of a threshold for defining clusters in the hierarchical method that maximizes agreement between the results of both methods. CONCLUSION: RAR has its major advantage in combining cluster distance and partition information, while the previously available methods used only the latter. RAR should be used in the research problems were HA was previously used, because in the absence of inter cluster distance effects it is an equally effective measure, and in the presence of distance effects it is a more complete one

Asymmetric magnetization reversal in exchange-biased hysteresis loops

This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.Polarized neutron reflectometry is used to probe the in-plane projection of the net-magnetization vector M of polycrystalline Fe films exchange coupled to twinned (110) MnF2 or FeF2 antiferromagnetic (AF) layers. The magnetization reversal mechanism depends upon the orientation of the cooling field with respect to the twinned microstructure of the AF, and whether the applied field is increased to (or decreased from) a positive saturating field; i.e., the magnetization reversal is asymmetric. The reversal of the sample magnetization from one saturated state to the other occurs via either domain wall motion or magnetization rotation on opposite sides of the same hysteresis loop

Clear-PEM: A PET imaging system dedicated to breast cancer diagnostics

The Clear-PEM scanner for positron emission mammography under development is described. The detector is based on pixelized LYSO crystals optically coupled to avalanche photodiodes and readout by a fast low-noise electronic system. A dedicated digital trigger (TGR) and data acquisition (DAQ) system is used for on-line selection of coincidence events with high efficiency, large bandwidth and small dead-time. A specialized gantry allows to perform exams of the breast and of the axilla. In this paper we present results of the measurement of detector modules that integrate the system under construction as well as the imaging performance estimated from Monte Carlo simulated data.http://www.sciencedirect.com/science/article/B6TJM-4M942B5-D/1/e8aea93baa1aeae3538ea200a5a5466

Is the meiofauna a good indicator for climate change and anthropogenic impacts?

Our planet is changing, and one of the most pressing challenges facing the scientific community revolves around understanding how ecological communities respond to global changes. From coastal to deep-sea ecosystems, ecologists are exploring new areas of research to find model organisms that help predict the future of life on our planet. Among the different categories of organisms, meiofauna offer several advantages for the study of marine benthic ecosystems. This paper reviews the advances in the study of meiofauna with regard to climate change and anthropogenic impacts. Four taxonomic groups are valuable for predicting global changes: foraminifers (especially calcareous forms), nematodes, copepods and ostracods. Environmental variables are fundamental in the interpretation of meiofaunal patterns and multistressor experiments are more informative than single stressor ones, revealing complex ecological and biological interactions. Global change has a general negative effect on meiofauna, with important consequences on benthic food webs. However, some meiofaunal species can be favoured by the extreme conditions induced by global change, as they can exhibit remarkable physiological adaptations. This review highlights the need to incorporate studies on taxonomy, genetics and function of meiofaunal taxa into global change impact research

Sensitivity of endorectal ecography in the staging of rectal chancre: correlation with pathological staging

Objectivo: Avaliar a sensibilidade da ecografia endorectal, em nossa experiência, no estadiamento do cancro do recto comparando com o resultado anatomopatológico. Material e métodos: Estudo retrospectivo, realizado entre Janeiro de 2005 e Agosto de 2009. Calculou-se a sensibilidade, a especificidade, o valor preditivo positivo e negativo para cada estadio T e N. Por meio da ela-boração de curvas ROC avaliou-se a precisão do estadiamento ecoendoscópico e por meio do teste de McNemar comparou-se com o resultado anatomopatológico. Resultados: Dos 112 doentes, 76 cumpriram os critérios de inclusão. Obtivemos uma eficácia de 75 a 97% para uT e de 75% para uN. Verificou-se sensibilidade, especificidade, valor preditivo positivo e negativo, respectivamente, de 63;98;92 e 89% para uT1; 71;76;54 e 88% para uT2; 67;81;73 e 76% para uT3; 100;97;60 e 100% para uT4; e 39;91;62 e 78% para uN. As curvas ROC indicaram que a ecografia endorectal é um bom teste para o estadiamento do T e razoável para o N. O teste de Mc-Nemar revelou que não há diferenças significativas entre o estadiamento ecoendoscópico e anatomopatológico (p>0,05). Conclusões: Conclui-se que a ecografia endorectal é uma importante ferramenta no estadiamento do cancro do recto, apresentando boa correlação com o resultado anatomopatológico.(undefined