Fundamentals of cell polarity and motility

Cell polarity is a fundamental characteristic regarding cell motility and division. In this work, first we analyze polarization from a biological vantage point, namely which are the molecules taking part on it and how it is experimentally observed. Then, we evaluate this mechanism by implementing a simple mathematical model, so that the fundamental concepts can be understood, and afterwards, a more complex modelization is analyzed, involving the kinetics of two proteins, so that we show how a simplified two-variable model can reproduce the symmetry breaking needed for polarity. Finally, the validity of this model is considered2021/202

A Comment on Griffin et al “My Quest, an Intervention Using Text Messaging to Improve Dietary and Physical Activity Behaviors and Promote Weight Loss in Low-Income Women”

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Lifestyle at Time of COVID-19: How Could Quarantine Affect Cardiovascular Risk

COVID-19 is causing a global pandemic with a high number of deaths and infected people. To contain the diffusion of COVID-19 virus, governments have enforced restrictions on outdoor activities or even collective quarantine on the population. Quarantine carries some long-term effects on cardiovascular disease, mainly related to unhealthy lifestyle and anxiety

Quarantine and Isolation during COVID-19 outbreak: A case of online diagnosis of supraventricular arrhythmia through telemedicine

The present case report highlights the usefulness of telemedicine during quarantine and isolation. The patient developed a supraventricular arrhythmia, and the diagnosis and management of the arrhythmia was done online

Nanomedicine and graphene-based materials: advanced technologies for potential treatments of diseases in the developing nervous system

Abstract: The interest in graphene-based nanomaterials (GBNs) application in nanomedicine, in particular in neurology, steadily increased in the last decades. GBNs peculiar physical–chemical properties allow the design of innovative therapeutic tools able to manipulate biological structures with subcellular resolution. In this review, we report GBNs applications to the central nervous system (CNS) when these nanomaterials are engineered as potential therapeutics to treat brain pathologies, with a focus on those of the pediatric age. We revise the state-of-the art studies addressing the impact of GBNs in the CNS, showing that the design of GBNs with different dimensions and chemical compositions or the use of specific administration routes and doses can limit unwanted side effects, exploiting GBNs efficacy in therapeutic approaches. These features favor the development of GBNs-based multifunctional devices that may find applications in the field of precision medicine for the treatment of disorders in the developing CNS. In this framework, we address the suitability of GBNs to become successful therapeutic tools, such as drug nano-delivery vectors when being chemically decorated with pharmaceutical agents and/or other molecules to obtain a high specific targeting of the diseased area and to achieve a controlled release of active molecules. Impact: The translational potential of graphene-based nanomaterials (GBNs) can be used for the design of novel therapeutic approaches to treat pathologies affecting the brain with a focus on the pediatric age.GBNs can be chemically decorated with pharmaceutical agents and molecules to obtain a highly specific targeting of the diseased site and a controlled drug release.The type of GBNs, the selected functionalization, the dose, and the way of administration are factors that should be considered to potentiate the therapeutic efficacy of GBNs, limiting possible side effects.GBNs-based multifunctional devices might find applications in the precision medicine and theranostics fields

GP-Unet: Lesion Detection from Weak Labels with a 3D Regression Network

We propose a novel convolutional neural network for lesion detection from weak labels. Only a single, global label per image - the lesion count - is needed for training. We train a regression network with a fully convolutional architecture combined with a global pooling layer to aggregate the 3D output into a scalar indicating the lesion count. When testing on unseen images, we first run the network to estimate the number of lesions. Then we remove the global pooling layer to compute localization maps of the size of the input image. We evaluate the proposed network on the detection of enlarged perivascular spaces in the basal ganglia in MRI. Our method achieves a sensitivity of 62% with on average 1.5 false positives per image. Compared with four other approaches based on intensity thresholding, saliency and class maps, our method has a 20% higher sensitivity.Comment: Article published in MICCAI 2017. We corrected a few errors from the first version: padding, loss, typos and update of the DOI numbe

Comparative transcriptomics of early petal development across four diverse species of Aquilegia reveal few genes consistently associated with nectar spur development

BackgroundPetal nectar spurs, which facilitate pollination through animal attraction and pollen placement, represent a key innovation promoting diversification in the genus Aquilegia (Ranunculaceae). Identifying the genetic components that contribute to the development of these three-dimensional structures will inform our understanding of the number and types of genetic changes that are involved in the evolution of novel traits. In a prior study, gene expression between two regions of developing petals, the laminar blade and the spur cup, was compared at two developmental stages in the horticultural variety A. coerulea 'Origami'. Several hundred genes were differentially expressed (DE) between the blade and spur at both developmental stages. In order to narrow in on a set of genes crucial to early spur formation, the current study uses RNA sequencing (RNAseq) to conduct comparative expression analyses of petals from five developmental stages between four Aquilegia species, three with morphologically variable nectar spurs, A. sibirica, A. formosa, and A. chrysantha, and one that lacks nectar spurs, A. ecalcarata.ResultsPetal morphology differed increasingly between taxa across the developmental stages assessed, with petals from all four taxa being indistinguishable pre-spur formation at developmental stage 1 (DS1) and highly differentiated by developmental stage 5 (DS5). In all four taxa, genes involved in mitosis were down-regulated over the course of the assessed developmental stages, however, many genes involved in mitotic processes remained expressed at higher levels later in development in the spurred taxa. A total of 690 genes were identified that were consistently DE between the spurred taxa and A. ecalcarata at all five developmental stages. By comparing these genes with those identified as DE between spur and blade tissue in A. coerulea 'Origami', a set of only 35 genes was identified that shows consistent DE between petal samples containing spur tissue versus those without spur tissue.ConclusionsThe results of this study suggest that expression differences in very few loci are associated with the presence and absence of spurs. In general, it appears that the spurless petals of A. ecalcarata cease cell divisions and enter the cell differentiation phase at an earlier developmental time point than those that produce spurs. This much more tractable list of 35 candidates genes will greatly facilitate targeted functional studies to assess the genetic control and evolution of petal spurs in Aquilegia

Bridging pro-inflammatory signals, synaptic transmission and protection in spinal explants in vitro

Multiple sclerosis is characterized by tissue atrophy involving the brain and the spinal cord, where reactive inflammation contributes to the neurodegenerative processes. Recently, the presence of synapse alterations induced by the inflammatory responses was suggested by experimental and clinical observations, in experimental autoimmune encephalomyelitis mouse model and in patients, respectively. Further knowledge on the interplay between pro-inflammatory agents, neuroglia and synaptic dysfunction is crucial to the design of unconventional protective molecules. Here we report the effects, on spinal cord circuits, of a cytokine cocktail that partly mimics the signature of T lymphocytes sub population Th1. In embryonic mouse spinal organ-cultures, containing neuronal cells and neuroglia, cytokines induced inflammatory responses accompanied by a significant increase in spontaneous synaptic activity. We suggest that cytokines specifically altered signal integration in spinal networks by speeding the decay of GABAA responses. This hypothesis is supported by the finding that synapse protection by a non-peptidic NGF mimetic molecule prevented both the changes in the time course of GABA events and in network activity that were left unchanged by the cytokine production from astrocytes and microglia present in the cultured tissue. In conclusion, we developed an important tool for the study of synaptic alterations induced by inflammation, that takes into account the role of neuronal and not neuronal resident cells

Evidenciando la evidencia

El Sistema de Educación Superior en Chile ha crecido rápidamente en los últimos años, en términos de matrícula, cantidad de instituciones, programas de pre y postgrado y recursos financieros. Y también se ha hecho más complejo, aumentando en forma creciente la variedad del sistema. En este contexto, es necesario disponer de información precisa, uniforme y transparente respecto de indicadores de gestión relevantes de cada uno de los actores involucrados en el modelo. Lo anterior, con el objetivo de que tanto los estudiantes que desean ingresar a las universidades, centros de formación técnica o institutos profesionales, sus padres y la sociedad en su conjunto, dispongan de antecedentes efectivos sobre el nivel de logro de estas instituciones y su contribución al desarrollo de la región y el país

Evidenciando la evidencia

El Sistema de Educación Superior en Chile ha crecido rápidamente en los últimos años, en términos de matrícula, cantidad de instituciones, programas de pre y postgrado y recursos financieros. Y también se ha hecho más complejo, aumentando en forma creciente la variedad del sistema. En este contexto, es necesario disponer de información precisa, uniforme y transparente respecto de indicadores de gestión relevantes de cada uno de los actores involucrados en el modelo. Lo anterior, con el objetivo de que tanto los estudiantes que desean ingresar a las universidades, centros de formación técnica o institutos profesionales, sus padres y la sociedad en su conjunto, dispongan de antecedentes efectivos sobre el nivel de logro de estas instituciones y su contribución al desarrollo de la región y el país