Recording from two neurons: second order stimulus reconstruction from spike trains and population coding

We study the reconstruction of visual stimuli from spike trains, recording simultaneously from the two H1 neurons located in the lobula plate of the fly Chrysomya megacephala. The fly views two types of stimuli, corresponding to rotational and translational displacements. If the reconstructed stimulus is to be represented by a Volterra series and correlations between spikes are to be taken into account, first order expansions are insufficient and we have to go to second order, at least. In this case higher order correlation functions have to be manipulated, whose size may become prohibitively large. We therefore develop a Gaussian-like representation for fourth order correlation functions, which works exceedingly well in the case of the fly. The reconstructions using this Gaussian-like representation are very similar to the reconstructions using the experimental correlation functions. The overall contribution to rotational stimulus reconstruction of the second order kernels - measured by a chi-squared averaged over the whole experiment - is only about 8% of the first order contribution. Yet if we introduce an instant-dependent chi-square to measure the contribution of second order kernels at special events, we observe an up to 100% improvement. As may be expected, for translational stimuli the reconstructions are rather poor. The Gaussian-like representation could be a valuable aid in population coding with large number of neurons

From juvenile parkinsonism to encephalitis lethargica, a new phenotype of post-streptococcal disorders: case report.

We report the case of a 16-year-old boy presented with a mild akinetic-rigid parkinsonism shortly after a post-streptococcal infection. After stopping corticoids, he had a rapid neurological deterioration to a fatal encephalitis lethargica-like syndrome. Serum analysis demonstrated consistently elevated anti-streptolysin-O. This case illustrates a new severe phenotype in the spectrum of the post-streptococcal disorders. This etiology should be considered in the differential diagnosis of a movement disorder with a rapid detrimental evolution

Changes in the biophysical properties of the cell membrane are involved in the response of neurospora crassa to staurosporine

Neurospora crassa is a non-pathogenic filamentous fungus widely used as a multicellular eukaryotic model. Recently, the biophysical properties of the plasma membrane of N. crassa conidia were thoroughly characterized. They evolve during conidial germination at a speed that depends on culture conditions, suggesting an important association between membrane remodeling and the intense membrane biogenesis that takes place during the germinative process. Staurosporine (STS) is a drug used to induce programmed cell death in various organisms. In N. crassa, STS up-regulates the expression of the ABC transporter ABC-3, which localizes at the plasma membrane and pumps STS out. To understand the role of plasma membrane biophysical properties in the fungal drug response, N. crassa was subjected to STS treatment during early and late conidial development stages. Following 1 h treatment with STS, there is an increase in the abundance of the more ordered, sphingolipid-enriched, domains in the plasmamembrane of conidia. This leads to higher fluidity in othermembrane regions. The global order of the membrane remains thus practically unchanged. Significant changes in sphingolipid-enriched domains were also observed after 15min challenge with STS, but they were essentially opposite to those verified for the 1 h treatment, suggesting different types of drug responses. STS effects on membrane properties that are more dependent on ergosterol levels also depend on the developmental stage. There were no alterations on 2 h-grown cells, clearly contrasting to what happens at longer growth times. In this case, the differences were more marked for longer STS treatment, and rationalized considering that the drug prevents the increase in the ergosterol/glycerophospholipid ratio that normally takes place at the late conidial stage/transition to the mycelial stage. This could be perceived as a drug-induced development arrest after 5 h growth, involving ergosterol, and pointing to a role of lipid rafts possibly related with an up-regulated expression of the ABC-3 transporter. Overall, our results suggest the involvement of membrane ordered domains in the response mechanisms to STS in N. crassa. Neurospora crassa is a non-pathogenic filamentous fungus widely used as a multicellular eukaryotic model. Recently, the biophysical properties of the plasma membrane of N. crassa conidia were thoroughly characterized. They evolve during conidial germination at a speed that depends on culture conditions, suggesting an important association between membrane remodeling and the intense membrane biogenesis that takes place during the germinative process. Staurosporine (STS) is a drug used to induce programmed cell death in various organisms. In N. crassa, STS up-regulates the expression of the ABC transporter ABC-3, which localizes at the plasma membrane and pumps STS out. To understand the role of plasma membrane biophysical properties in the fungal drug response, N. crassa was subjected to STS treatment during early and late conidial development stages. Following 1 h treatment with STS, there is an increase in the abundance of the more ordered, sphingolipid-enriched, domains in the plasmamembrane of conidia. This leads to higher fluidity in othermembrane regions. The global order of the membrane remains thus practically unchanged. Significant changes in sphingolipid-enriched domains were also observed after 15min challenge with STS, but they were essentially opposite to those verified for the 1 h treatment, suggesting different types of drug responses. STS effects on membrane properties that are more dependent on ergosterol levels also depend on the developmental stage. There were no alterations on 2 h-grown cells, clearly contrasting to what happens at longer growth times. In this case, the differences were more marked for longer STS treatment, and rationalized considering that the drug prevents the increase in the ergosterol/glycerophospholipid ratio that normally takes place at the late conidial stage/transition to the mycelial stage. This could be perceived as a drug-induced development arrest after 5 h growth, involving ergosterol, and pointing to a role of lipid rafts possibly related with an up-regulated expression of the ABC-3 transporter. Overall, our results suggest the involvement of membrane ordered domains in the response mechanisms to STS in N. crassa.Fundação para a Ciência e a Tecnologia (FCT), Portugal, is acknowledged for grants PTDC/BBB-BQB/6071/2014, UID/Multi/00612/2013, IF/00317/2012, and PT2020 referring to research unit 4293. FS acknowledges Ph.D. scholarship SFRH/BD/108031/2015, also from FCT

(R)-(1-Ammonio­prop­yl)phospho­nate

The title compound, C3H10NO3P, crystallizes in its zwitterionic form, H3N+CH(C2H5)PO(O−)(OH), with the asymmetric unit being composed by two of such entities (Z′ = 2). The crystal packing leads to a sequence of hydro­phobic and hydro­philic layers. While the hydro­phobic layer comprises the aliphatic substituent groups, the hydro­philic one is held together by a series of strong and rather directional N+—H⋯O and O—H⋯O hydrogen bonds

Biocontrole da mela do feijoeiro comum (Rhizoctonia solani) por rizobactérias em condições de campo.

Neste trabalho, buscou-se testar oito rizobactérias obtidas de plantios de feijoeiro nos campos experimentais da Embrapa Rondônia e previamente selecionadas em casa-de-vegetação

Structural behaviour analysis of Faria Guimarães station

No presente estudo efectua-se a modelação e análise do comportamento estrutural da estação Faria Guimarães, do Metro do Porto. A estação é constituída por um cruzamento oblíquo de duas grandes galerias executadas através do método SEM/NATM. A obra é de elevada complexidade devido aos condicionamentos geométricos da estação e obras adjacentes, à grande heterogeneidade do maciço e à ocupação intensa da superfície. A análise do comportamento estrutural da estação foi realizada recorrendo a modelos numéricos 2D e 3D, bem como a resultados obtidos com a observação da estação.In present paper the modelling and structural behaviour analysis of the Faria Guimarães station, of Metro do Porto, is presented. The station includes the inclined intersection of two large galleries executed through SEM/NATM method. The work is highly complex due to geometric limitations of the station and adjacent works, the heterogeneity of the rock mass and the dense occupation at surface. The structural behaviour analysis of the station was performed using 2D and 3D numerical models, as well as results obtained through the observation of the station.Fundação para a Ciência e Tecnologia (FCT) - Projecto POCI/ECM/57495/2004, intitulado Geotechnical Risk in Tunnels for High Speed Trains

NEFRECTOMIA PARCIAL – A EXPERIÊNCIA DE 10 ANOS DO HOSPITAL DE SANTO ANTÓNIO

A nefrectomia parcial (NP) é uma técnica reconhecida no tratamento de diferentes patologias renais,nomedamente na oncológica. Os autores apresentam a sua casuística dos últimos 10 anos, com avaliação dos índices de recorrência e sobrevivência

Morphological transition of Helicobacter pylori adapted to water

To view the supplementary data that accompany this paper please visit the journal website at: www. futuremedicine.com /doi/full/10.2217/fmb-2016-0174.Aim: This study aims to investigate the morphological transition of Helicobacter pylori during adaptation to water. Materials \& methods: Different strains were adapted to water. Changes regarding cultivability and cellular morphology were recorded. Expression of 11 genes involved in H. pylori morphological changes was evaluated by real-time PCR. Results: H. pylori presented increased cultivability in water after adaptation. The permanent loss of the spiral shape was observed, but no transition into coccoid form has occurred. Expression levels of genes involved in peptidoglycan assembly of H. pylori 26695 have shown significant changes between adapted and nonadapted strains. Conclusion: Adaption to water favors the culturable phenotype and the morphological transition to the rod shape, into a process that implicates the peptidoglycan turnover.This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the project ‘Heliwater’ (PTDC/BIA-MIC/108811/2008), the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte. No writing assistance was utilized in the production of this manuscript.info:eu-repo/semantics/publishedVersio

Characterization of multispecies biofilms by peptide nucleic acid fluorescence in situ hybridization (PNA-FISH)

Our current understanding of biofilms in the environment and in health indicates that these structures are typically composed of many different microbial species. However, the lack of reliable techniques for the quantification, visualization and discrimination of each population has meant that studies assessing multi-species interactions between sessile microorganisms are scarce and low-throughput. Employing novel peptide nucleic acid fluorescence in situ hybridization (PNA-FISH) methods, we present here a characterization of Salmonella enterica/Listeria monocytogenes/Escherichia coli single, dual and tri-species biofilms in seven support materials. Ex-situ, we were able to relate quantitatively the populations of ~56 mixed species biofilms up to 48h, regardless of the support material.In situ a correct quantification remained more elusive, but a qualitative understanding of biofilm structure and composition is clearly possible for most support materials. Regarding biological behavior, composition of mixed-culture biofilm seems to be the final result of competition between microorganisms, both for available nutrients and for free surface to colonize. It is also suggested that the ability to form biofilm is mostly a species-dependent phenomenon rather than surfacedependent, as six of the materials maintained both the species profile and had similar total cell numbers. The exception was copper, that inhibited the biofilm formation for the species tested. Our findings concluded that, using a single method, such as PNA-FISH, to confidently discriminate multispecies early-stage biofilms, researchers can infer about spatial organization, intra- or inter-specie interaction and also assess viable but not cultivable states