NUMERICAL MODELS AS TOOLS TO UNDERSTAND THE DYNAMICS IN BAYS: CASE OF STUDY CHETUMAL BAY, QUINTANA ROO

In this study performed the simulation of currents generated by the wind on the Bay of Chetumal, Quintana Roo through the use of a stationary shallow-water model. A homogeneous climatic wind was used for the entire Bay, with a velocity of 3m·s-1 , and directions North, South, Northeast, Northwest, East, Southeast, Southwest and West. The results showed a rather complex dynamics in Chetumal Bay, in which important turns were observed in deep areas, with speeds reaching up to 13 cm·s-1

Entorno de aprendizaje colaborativo para la enseñanza del Baloncesto

Cuba es ante el mundo una potencia deportiva, cuya base se encuentra en escuelas las escuelas deportivas, donde se forman y educan nuestros futuros atletas, es por eso la importancia que reviste el empleo de nuevas técnicas para la enseñanza de los deportes. En la formación táctica del jugador, se debe tener en cuenta tanto la formación teórica como la práctica. El uso de la informática en la enseñanza de los deportes, como método adjunto al entrenamiento específicamente en tema de la táctica en el alto rendimiento, en nuestro país, no esta ampliamente explorado, ni utilizado, es por eso que nuestro trabajo esta encaminado a elaborar una herramienta de aprendizaje colaborativo asistido por computadora siguiendo un sistema de acciones teóricas que permita un mayor aprendizaje de la táctica colectiva a la ofensiva en el baloncesto

Cell cycle reentry triggers hyperploidization and synaptic dysfunction followed by delayed cell death in differentiated cortical neurons

Cell cycle reentry followed by neuronal hyperploidy and synaptic failure are two early hallmarks of Alzheimer’s disease (AD), however their functional connection remains unexplored. To address this question, we induced cell cycle reentry in cultured cortical neurons by expressing SV40 large T antigen. Cell cycle reentry was followed by hyperploidy in ~70% of cortical neurons, and led to progressive axon initial segment loss and reduced density of dendritic PSD-95 puncta, which correlated with diminished spike generation and reduced spontaneous synaptic activity. This manipulation also resulted in delayed cell death, as previously observed in AD-affected hyperploid neurons. Membrane depolarization by high extracellular potassium maintained PSD-95 puncta density and partially rescued both spontaneous synaptic activity and cell death, while spike generation remained blocked. This suggests that AD-associated hyperploid neurons can be sustained in vivo if integrated in active neuronal circuits whilst promoting synaptic dysfunction. Thus, cell cycle reentry might contribute to cognitive impairment in early stages of AD and neuronal death susceptibility at late stages.This work was supported by Ministerio de Economía y Competitividad Grants SAF2015-68488-R (J.M.F.) and BFU2013-47265-R and BFU2016-75107-P (G.P.), and Intramural Grant 201620I017 (G.P.).Peer reviewe

Melanopsin for precise optogenetic activation of astrocyte-neuron networks

Optogenetics has been widely expanded to enhance or suppress neuronal activity and it has been recently applied to glial cells. Here, we have used a new approach based on selective expression of melanopsin, a G-protein-coupled photopigment, in astrocytes to trigger Ca2+ signaling. Using the genetically encoded Ca2+ indicator GCaMP6f and two-photon imaging, we show that melanopsin is both competent to stimulate robust IP3-dependent Ca2+ signals in astrocyte fine processes, and to evoke an ATP/Adenosine-dependent transient boost of hippocampal excitatory synaptic transmission. Additionally, under low-frequency light stimulation conditions, melanopsin-transfected astrocytes can trigger long-term synaptic changes. In vivo, melanopsin-astrocyte activation enhances episodic-like memory, suggesting melanopsin as an optical tool that could recapitulate the wide range of regulatory actions of astrocytes on neuronal networks in behaving animals. These results describe a novel approach using melanopsin as a precise trigger for astrocytes that mimics their endogenous G-protein signaling pathways, and present melanopsin as a valuable optical tool for neuron-glia studies.The authors thank Dr. J. Chen (UCSD, CA, USA) for providing IP3R2−/− mice; Dr. W. Buño, Dr. E. Martin and Dr. Araque for helpful comments; Dr. JA Esteban, C. Sánchez and M.A. Muñoz for helpful assistance with the two‐photon technical assistance; Dr. M. Valero for MATLAB advice. This work was supported by PhD fellowship program (MINECO, BES‐2014‐067594) to S.M; and MINECO grants (BFU2013‐47265R; Intramural 201620I017; BFU2016‐75107‐P) to G.P

Sex-specific regulation of inhibition and network activity by local aromatase in the mouse hippocampus

Cognitive function relies on a balanced interplay between excitatory and inhibitory neurons (INs), but the impact of estradiol on IN function is not fully understood. Here, we characterize the regulation of hippocampal INs by aromatase, the enzyme responsible for estradiol synthesis, using a combination of molecular, genetic, functional and behavioral tools. The results show that CA1 parvalbumin-expressing INs (PV-INs) contribute to brain estradiol synthesis. Brain aromatase regulates synaptic inhibition through a mechanism that involves modification of perineuronal nets enwrapping PV-INs. In the female brain, aromatase modulates PV-INs activity, the dynamics of network oscillations and hippocampal-dependent memory. Aromatase regulation of PV-INs and inhibitory synapses is determined by the gonads and independent of sex chromosomes. These results suggest PV-INs are mediators of estrogenic regulation of behaviorally-relevant activity.We thank E. Jiménez, A. Arroyo, and C. Sanmartín Segovia for help with image analysis; C. Sánchez for Python data processing scripts, J.G. Yagüe and M.A. Arévalo for production and validation of aromatase antibody; A.P. Arnold (UCLA, USA) for the kind gift of the FCG mice and A. Bacci (ICM, Paris, France) and L.M. García-Segura (Cajal Institute, Madrid, Spain) for helpful discussions on the manuscript. This work was supported by grants: RYC-2015-18545 (to P.M.), funded by MCIN/AEI/ 10.13039/501100011033 by “ESF Investing in your future”, BFU2017-84490-P (to P.M.) and RTI2018-098581-B-I00 (to L.M.P.) funded by MCIN/AEI/ 10.13039/501100011033 by “ERDF A way of making Europe” and PID2020-112824GB-100 (to P.M.) funded by MCIN/AEI/ 10.13039/501100011033. N.C.-A. is supported by the Ph.D. fellowship PRE2018-084857 funded by MCIN/AEI/10.13039/501100011033 by “ESF Investing in your future”. A.S.-A. is supported by the Juan de la Cierva program FJCI-2017-32719 funded by MCIN/AEI/10.13039/501100011033

Elevated circulating levels of IL-21 and IL-22 define a cytokine signature profile in type 2 autoimmune hepatitis patients

Background and aims. Autoimmune hepatitis (AIH) is a chronic inflammatory condition of the liver in which the immunological mechanisms involved in tissue destruction and/or repair are still unclear. Different pro-inflammatory cytokines have been shown to play a determinant role in AIH pathogenesis. Here, we aim to compare the circulating levels of pro-and anti-inflammatory cytokines such as IL-6, TNF-α, IL-17A/F, IL-21, IL-22, IL-23, and IL-10 in patients with type 2 AIH compared to patients with type 1 AIH and healthy controls (HC). Fourty-six Mexican patients with AIH were recruited in our study. Patients were classified as type 1 or 2 AIH based on immune serological markers. Fourty-four serum samples from healthy individuals were included as controls. Serum cytokine levels were determined by ELISA technique.Results. Compared to healthy controls, serum levels of IL-17F, IL-21, IL-23, IL-10, IL-6, and TNF-α, but not IL-17A and IL-22, were significantly increased in AIH patients. When patients were grouped by aminotransferase activity, a biomarker of active disease, a positive correlation between serum IL-17F and alanine transaminase (rs: 0.4739; P = 0.0009) and aspartate transaminase (rs: 0.4984; P = 0.0004) levels was found. A cytokine signature profile associated with type 2 AIH was characterized by high serum IL-21 (type 1 AIH: 0.66 pg/mL; type 2 AIH: 331.1 pg/mL; P = 0.0042) and IL-22 (type 1 AIH: 0.1 pg/mL; type 2 AIH: 55.26 pg/mL; P = 0.0028) levels.Conclusions. We show for the first time, differential regulation of certain pro-inflammatory cytokines associated with disease progression and AIH type in Mexican patients