Development and distribution of the non-indigenous Pacific oyster (Crassostrea gigas) in the Dutch Wadden Sea

Pacific oysters (Crassostrea gigas) were first observed in the Dutch Wadden Sea near Texel in 1983. The population increased slowly in the beginning but grew exponentially from the mid-1990s onwards, although now some stabilisation seems to be occurring. They occur on a variety of substrates such as mussel beds (Mytilus edulis), shell banks, dikes and poles. After initial settlement spat may fall on older individuals and congregate to dense clumps and subsequently form reefs. Individual Pacific oysters grow 3–4 cm long in their first year and 2–3 cm in their second year. Many mussel beds (Mytilus edulis) are slowly taken over by Pacific oysters, but there are also several reports of mussel spat settling on Pacific oyster reefs. This might in the end result in combined reefs. Successful Pacific oyster spat fall seems to be related to high summer temperatures, but also after mild summers much spat can be found on old (Pacific oyster) shells. Predation is of limited importance. Mortality factors are unknown, but every now and then unexplained mass mortality occurs. The gradual spread of the Pacific oyster in the Dutch Wadden Sea is documented in the first instance based on historical and anecdotal information. At the start of the more in-depth investigation in 2002, Pacific oysters of all size classes were already present near Texel. Near Ameland the development could be followed from the first observed settlement. On dense reefs each square metre may contain more than 500 adult Pacific oysters, weighing more than 100 kg per m² fresh weigh

Digital Skills, Labour Market, and Productivity

Analysis of the impact of possessing digital skills on labour market outcomes

Importance of the solvation degree of peptide-resin beads for amine groups determination by the picric acid method

The classic and important picric acid method used in polymers biochemical and chemical fields of polymers for amine group quantification was chosen in this work as a model for evaluating the influence of the resin bead solvation during an analytical procedure. It was observed that this method, proposed almost three decades ago, failed to quantify amine groups of peptidyl-resin containing aggregating and polar sequence. This was due to inefficient solvation of resin beads when only CH2Cl2 was used for picrate anion binding and subsequent washing steps. It was demonstrated that the use of CH2Cl2/DMF (dimethylformamide) and CH2Cl2/EtOH solutions during these steps allows correct determination of peptidyl-resin amine groups. Besides the importance for the solid phase peptide synthesis methodology itself, these findings also represent the first quantitative demonstration of the relationship between solvation degree and the efficiency of a polymer-supported analytical method.O clássico e importante método do ácido pícrico, usado nas áreas de bioquímica e química de polímeros para a quantificação de grupos aminos, foi escolhido neste trabalho como modelo para investigar a importância do grau de solvatação de grãos poliméricos durante o protocolo analítico. Verificou-se que este método, proposto há cerca de três décadas atrás, falha na quantificação de grupos amino de peptidil-resinas contendo seqüência agregante e polar. Isto ocorre devido à solvatação insuficiente dos grãos quando apenas o CH2Cl2 é utilizado na etapa de ligação do ânion picrato e na subsequente etapa de lavagem. Demonstrou-se que a utilização nestas etapas, de soluções de CH2Cl2/DMF (dimetilformamida) e de CH2Cl2/EtOH permite uma determinação correta dos grupos amínicos de peptídil-resinas. Além da importância em si para o método da síntese de peptídeos em fase sólida, estes resultados representam também a primeira comprovação experimental da correlação quantitativa existente entre o grau de solvatação e a eficiência de um método analítico efetuado em grãos de resinas.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Federal de São Paulo (UNIFESP) Departamento de BiofísicaUNIFESP, Depto. de BiofísicaSciEL

ProNGF Is a Cell-Type-Specific Mitogen for Adult Hippocampal and for Induced Neural Stem Cells

The role of proNGF, the precursor of Nerve Growth Factor (NGF), on the biology of adult neural stem cells (aNSCs) is still unclear. Here I analyzed adult hippo-campal neurogenesis in AD11 transgenic mice, in which the constitutive expression of anti-NGF antibody leads to an imbalance of proNGF over mature NGF. I found in-creased proliferation of progenitors but a reduced neurogenesis in the AD11 DG- hippocampus (HP-DG). Also in vitro, AD11 hippocampal neural stem cells (NSCs) pro-liferated more but were unable to differentiate into morphologically mature neu-rons. By treating wild-type (WT) hippocampal progenitors with the uncleavable form of proNGF (proNGF-KR) I demonstrated that proNGF acts as mitogen on aNSCs at low concentration. The mitogenic effect of proNGF was specifically addressed to the radial glia-like (RGL) neural stem cells through the induction of cyclin D1 expression. These cells express high level of p75NTR, as demonstrated by immunofluorescence analyses performed ex vivo on RGL cells isolated from freshly-dissociated HP-DG or selected in vitro from NSCs by LIF (leukemia inhibitory factor). Clonogenic assay per-formed in the absence of mitogens showed that RGLs respond to proNGF-KR by re-activating their proliferation and thus leading to neurospheres formation. The mito-genic effect of proNGF was further exploited in the expansion of mouse induced Neural Stem Cells (iNSCs). Chronic exposure of iNSCs to proNGF-KR increased their proliferation. Altogether, I demonstrated that proNGF acts as mitogen on hippo-campal and induced neural stem cells.The role of proNGF, the precursor of nerve growth factor (NGF), in the biology of adult neural stem cells (aNSCs) is still unclear. Here, we analyzed adult hippocampal neurogenesis in AD11 transgenic mice, in which the constitutive expression of anti-NGF antibody leads to an imbalance of proNGF over mature NGF. We found increased proliferation of progenitors but a reduced neurogenesis in the AD11 dentate gyrus (DG)-hippocampus (HP). Also in vitro, AD11 hippocampal neural stem cells (NSCs) proliferated more, but were unable to differentiate into morphologically mature neurons. By treating wild-type hippocampal progenitors with the uncleavable form of proNGF (proNGF-KR), we demonstrated that proNGF acts as mitogen on aNSCs at low concentration. The mitogenic effect of proNGF was specifically addressed to the radial glia-like (RGL) stem cells through the induction of cyclin D1 expression. These cells express high levels of p75NTR, as demonstrated by immunofluorescence analyses performed ex vivo on RGL cells isolated from freshly dissociated HP-DG or selected in vitro from NSCs by leukemia inhibitory factor. Clonogenic assay performed in the absence of mitogens showed that RGLs respond to proNGF-KR by reactivating their proliferation and thus leading to neurospheres formation. The mitogenic effect of proNGF was further exploited in the expansion of mouse-induced neural stem cells (iNSCs). Chronic exposure of iNSCs to proNGF-KR increased their proliferation. Altogether, we demonstrated that proNGF acts as mitogen on hippocampal and iNSCs. Stem Cells 2019;37:1223–1237

Dissecting the mechanism of action of actinoporins. Role of the N-terminal amphipathic α-helix in membrane binding and pore activity of sticholysins I and II

<div><p>Actinoporins sticholysin I and sticholysin II (St I, St II) are proposed to lyse model and biomembranes via toroidal pore formation by their N-terminal domain. Based on the hypothesis that peptide fragments can reproduce the structure and function of this domain, the behavior of peptides containing St I residues 12–31 (StI_12-31), St II residues 11–30 (StII_11-30), and its TOAC-labeled analogue (N-TOAC-StII_11-30) was examined. Molecular modeling showed a good match with experimental structures, indicating amphipathic α-helices in the same regions as in the toxins. CD spectra revealed that the peptides were essentially unstructured in aqueous solution, acquiring α-helical conformation upon interaction with micelles and large unilamellar vesicles (LUV) of variable lipid composition. Fluorescence quenching studies with NBD-containing lipids indicated that N-TOAC-StII_11-30’s nitroxide moiety is located in the membranes polar head group region. Pyrene-labeled phospholipid inter-leaflet redistribution suggested that the peptides form toroidal pores, according to the mechanism of action proposed for the toxins. Binding occurred only to negatively charged LUV, indicating the importance of electrostatic interactions; in contrast the peptides bound to both negatively charged and zwitterionic micelles, pointing to a lesser influence of these interactions. In addition, differences between bilayers and micelles in head group packing and in curvature led to differences in peptide-membrane interaction. We propose that the peptides topography in micelles resembles that of the toxins in the toroidal pore. The peptides mimicked the toxins permeabilizing activity, St II peptides being more effective than StI_12-31. To our knowledge, this is the first demonstration that differences in the toxins N-terminal amphipathic α-helix play a role in the difference between St I and St II activities.</p></div

The State of the ReCLes. pt CLIL training project

Content and Language Integrated Learning (CLIL), an area that has only recently been more thoroughly explored for appropriate use at higher levels of education, has been one of the research areas identified by the Association of Language Centers in Higher Education in Portugal (ReCLes.pt). ReCLes.pt members – administration and research professors are striving to make a difference in the paucity of scientific publications in this area with the creation of their national program for training content teachers in Portuguese higher education. To best learn from each other in a collaborative network and apply well-informed teaching and learning methodology to English-taught classrooms, the underlying concepts range from classroom management and scaffolding to learner autonomy and from Web 2.0 tools to terminology-based learning. As an update of the current state of the art as interpreted in this project, the outreach and reception will be described in full with attention to some detailed examples of the more successful aspects as well as others where we have found room for improvement. Recommendations will be made for other networks and individual schools aiming to effectively prepare their students for the market by using an integrated approach to content and language learning. This paper reports on the current state of the ongoing ReCLes.pt CLIL Training Project, financed in part by the FCT (the Portuguese Foundation for Science and Technology), with project members from a number of universities and polytechnics across Portugal.info:eu-repo/semantics/publishedVersio

Effects of miRNA-15 and miRNA-16 expression replacement in chronic lymphocytic leukemia : implication for therapy

This work was supported by: Associazione Italiana Ricerca sul Cancro (AIRC) Grant 5 x mille n.9980, (to M.F., F.M. A. N., P.T. and M.N.) ; AIRC I.G. n. 14326 (to M.F.), n.10136 and 16722 (A.N.), n.15426 (to F.F.). AIRC and Fondazione CaRiCal co-financed Multi Unit Regional Grant 2014 n.16695 (to F.M.). Italian Ministry of Health 5x1000 funds (to S.Z. and F.F). A.G R. was supported by Associazione Italiana contro le Leucemie-Linfomi-Mielomi (AIL) Cosenza - Fondazione Amelia Scorza (FAS). S.M. C.M., M.C., L.E., S.B. were supported by AIRC.Peer reviewedPostprin