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

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

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

Super-hydrodynamic limit in interacting particle systems

This paper is a follow-up of the work initiated in [3], where it has been investigated the hydrodynamic limit of symmetric independent random walkers with birth at the origin and death at the rightmost occupied site. Here we obtain two further results: first we characterize the stationary states on the hydrodynamic time scale and show that they are given by a family of linear macroscopic profiles whose parameters are determined by the current reservoirs and the system mass. Then we prove the existence of a super-hyrdrodynamic time scale, beyond the hydrodynamic one. On this larger time scale the system mass fluctuates and correspondingly the macroscopic profile of the system randomly moves within the family of linear profiles, with the randomness of a Brownian motion.Comment: 22 page