Presubiculum stimulation in vivo evokes distinct oscillations in superficial and deep entorhinal cortex layers in chronic epileptic rats

The characteristic cell loss in layer III of the medial entorhinal area (MEA-III) in human mesial temporal lobe epilepsy is reproduced in the rat kainate model of the disease. To understand how this cell loss affects the functional properties of the MEA, we investigated whether projections from the presubiculum (prS), providing a main input to the MEA-III, are altered in this epileptic rat model. Injections of an anterograde tracer in the prS revealed bilateral projection fibers mainly to the MEA-III in both control and chronic epileptic rats. We further examined the prS-MEA circuitry using a 16-channel electrode probe covering the MEA in anesthetized control and chronic epileptic rats. With a second 16-channel probe, we recorded signals in the hippocampus. Current source density analysis indicated that, after prS double-pulse stimulation, afterdischarges in the form of oscillations (20-45 Hz) occurred that were confined to the superficial layers of the MEA in all epileptic rats displaying MEA-III neuronal loss. Slower oscillations (theta range) were occasionally observed in the deep MEA layers and the dentate gyrus. This kind of oscillation was never observed in control rats. We conclude that dynamical changes occur in an extensive network within the temporal lobe in epileptic rats, manifested as different kinds of oscillations, the characteristics of which depend on local properties of particular subareas. These findings emphasize the significance of the entorhinal cortex in temporal lobe epilepsy and suggest that the superficial cell layers could play an important role in distributing oscillatory activity.status: publishe

Rheological behavior of thermoreversible k-carrageenan/nanosilica gels

The rheological behavior of silica/κ-carrageenan nanocomposites has been investigated as a function of silica particle size and load. The addition of silica nanoparticles was observed to invariably impair the gelation process, as viewed by the reduction of gel strength and decrease of gelation and melting temperatures. This weakening effect is seen, for the lowest particle size, to become slightly more marked as silica concentration (or load) is increased and at the lowest load as particle size is increased. These results suggest that, under these conditions, the particles act as physical barriers to polysaccharide chain aggregation and, hence, gelation. However, for larger particle sizes and higher loads, gel strength does not weaken with size or concentration but, rather, becomes relatively stronger for intermediate particles sizes, or remains unchanged for the largest particles, as a function of load. This indicates that larger particles in higher number do not seem to increasingly disrupt the gel, as expected, but rather promote the formation of stable gel network of intermediate strength. The possibility of this being caused by the larger negative surface charge found for the larger particles is discussed. This may impede further approximation of neighboring particles thus leaving enough inter-particle space for gel formation, taking advantage of a high local polysaccharide concentration due to the higher total space occupied by large particles at higher loads.FCT - PTDC/QUI/67712/2006FEDE

Potential of the endophyte Penicillium commune in the control of olive anthracnose via induction of antifungal volatiles in host plant

Olive anthracnose, caused by several Colletotrichum species, is the most economically harmful fruit disease of the olive crop. This work aimed to evaluate the ability of the endophyte Penicillium commune CIMO 14FM009 to protect the olive tree against Colletotrichum nymphaeae via induction of plant volatile organic compounds (VOCs). Accordingly, olive tree branches were inoculated with the endophyte and one month later with the pathogen. After 0, 3, and 24 h of pathogen inoculation, the volatile composition of leaves and fruits was analyzed by HSSPME- GC/MS, and compared with controls (branches inoculated with buffer, endophyte, or pathogen). The effect of plant-derived volatiles on C. nymphaeae was also evaluated. Penicillium commune induced the release of VOCs on the olive trees, with the capacity to reduce significantly the growth (up to 1.4-fold) and sporulation (up to 1.2-fold) of C. nymphaeae. This effect was most notorious on olives than on leaves, and occurred 3 h after pathogen-challenge, suggesting the need for a stressful stimulus for the production of antifungal VOCs. The observed inhibition was associated to a specific set of VOCs released from olives (mostly belonging to the alcohols and esters chemical classes) and leaves (mostly belonging to the alkenes). Curiously, a set of VOCs belonging to alkene, alkane and ester classes, were emitted exclusively in olive branches inoculated with C. nymphaeae. These findings provide new possibilities for controlling olive anthracnose using P. commune and/or volatiles, which efficacy should be tested in future works.This work is supported by FEDER funds through the COMPETE (Operational Program for Competitiveness Factors) and by National funds through the FCT (Foundation for Science and Technology) in the scope of the project POCI-01–0145-FEDER-031133 “MicOlives - Exploiting plant induced resistance by beneficial fungi as a new sustainable approach to olive crop protection”, Horizon 2020, the European Union’s Framework Programme for Research and Innovation, in the scope of the project PRIMA/0002/2018 “INTOMED- Innovative tools to combat crop pests in the Mediterranean”, and IFAP via the project “Bio4Med - Implementation of innovative strategies to increase sustainability in perennial Mediterranean crops”, as well as the Mountain Research Center - CIMO (UIDB/00690/2020; UIDP/00690/2020) and SusTEC (LA/P/0007/2020).info:eu-repo/semantics/publishedVersio

Peripheral nervous system plasmalogens regulate Schwann cell differentiation and myelination

Rhizomelic chondrodysplasia punctata (RCDP) is a developmental disorder characterized by hypotonia, cataracts, abnormal ossification, impaired motor development, and intellectual disability. The underlying etiology of RCDP is a deficiency in the biosynthesis of ether phospholipids, of which plasmalogens are the most abundant form in nervous tissue and myelin; however, the role of plasmalogens in the peripheral nervous system is poorly defined. Here, we used mouse models of RCDP and analyzed the consequence of plasmalogen deficiency in peripheral nerves. We determined that plasmalogens are crucial for Schwann cell development and differentiation and that plasmalogen defects impaired radial sorting, myelination, and myelin structure. Plasmalogen insufficiency resulted in defective protein kinase B (AKT) phosphorylation and subsequent signaling, causing overt activation of glycogen synthase kinase 3β (GSK3β) in nerves of mutant mice. Treatment with GSK3β inhibitors, lithium, or 4-benzyl-2-methyl-1,2,4-thiadiazolidine-3,5-dione (TDZD-8) restored Schwann cell defects, effectively bypassing plasmalogen deficiency. Our results demonstrate the requirement of plasmalogens for the correct and timely differentiation of Schwann cells and for the process of myelination. In addition, these studies identify a mechanism by which the lack of a membrane phospholipid causes neuropathology, implicating plasmalogens as regulators of membrane and cell signaling.We thank Paula Sampaio for microscopy support, Paula Magalhdes for genotyping, and Isabel Carvalho, Sofia Lamas, and Fatima Martins for excellent animal care. We are grateful to P. Brophy (University of Edinburgh) for the DRP2 antibody and to M. Baes (K.U. Leuven) for providing the Gnpat mouse strain. This work was funded by the Research Foundation of the European Leukodystrophy Association (ELA 2008-009C4, ELA 2010-042C5), by FEDER Funds through the Operational Competitiveness Program - COMPETE, and by national funds through the FCT - Fundacao para a Ciencia e a Tecnologia under the project FCOMP-01-0124-FEDER-015970 (PTDS/SAU-ORG/112406/2009). P. Brites is an FCT Investigator, and T. Ferreira da Silva was supported by the FCT (SFRH/BD/88160/2012)

Compilation of parameterized seismogenic sources in Iberia for the SHARE European-scale seismic source model.

Abstract: SHARE (Seismic Hazard Harmonization in Europe) is an EC-funded project (FP7) that aims to evaluate European seismic hazards using an integrated, standardized approach. In the context of SHARE, we are compiling a fully-parameterized active fault database for Iberia and the nearby offshore region. The principal goal of this initiative is for fault sources in the Iberian region to be represented in SHARE and incorporated into the source model that will be used to produce seismic hazard maps at the European scale. The SHARE project relies heavily on input from many regional experts throughout the Euro-Mediterranean region. At the SHARE regional meeting for Iberia, the 2010 Working Group on Iberian Seismogenic Sources (WGISS) was established; these researchers are contributing to this large effort by providing their data to the Iberian regional integrators in a standardized format. The development of the SHARE Iberian active fault database is occurring in parallel with IBERFAULT, another ongoing effort to compile a database of active faults in the Iberian region. The SHARE Iberian active fault database synthesizes a wide range of geological and geophysical observations on active seismogenic sources, and incorporates existing compilations (e.g., Cabral, 1995; Silva et al., 2008), original data contributed directly from researchers, data compiled from the literature, parameters estimated using empirical and analytical relationships, and, where necessary, parameters derived using expert judgment. The Iberian seismogenic source model derived for SHARE will be the first regional-scale source model for Iberia that includes fault data and follows an internationally standardized approach (Basili et al., 2008; 2009). This model can be used in both seismic hazard and risk analyses and will be appropriate for use in Iberian- and European-scale assessments

Tranfer+.Tec. Castanha

O Projeto “Tranfer+.Tec.Castanha” tem como objetivo central o dinamizar o ecossistema regional de inovação e estimular a transferência de tecnologia e de conhecimento da fileira da Castanha, para o setor empresarial da região, nacional e internacional, com vista ao desenvolvimento de novos produtos e ao desenvolvimento de projetos de transferência e utilização de conhecimento. Foram definidas seis ações e 19 atividades específicas. As ações são: 1 - Levantamento de Necessidades de Tecnologia e Conhecimento das empresas da fileira da Castanha; 2 - Disseminação e de difusão de novos conhecimentos e tecnologias geradas no âmbito da I&D, através de ações setoriais de experimentação, no domínio das pragas e doenças do castanheiro; 3 - Interação com o ambiente empresarial, para a sensibilização, partilha e mapeamento de oportunidades de desenvolvimento de tecnologias e conhecimentos na fileira da Castanha e criação de comunidades de inovação; 4 - Valorização económica dos resultados da investigação; 5 - Iniciativas de interação com o ambiente empresarial para a promoção nacional e internacional de tecnologias e de conhecimento; 6 - Promoção e divulgação do projeto. Será apresentado um balanço das atividades já realizadas e a realizar no próximo ano.Projeto “Tranfer+.Tec.Castanha: Reforço da transferência de conhecimento científico e tecnológico da fileira da castanha para o setor empresarial. NORTE 2020info:eu-repo/semantics/publishedVersio