Effects of Estrogen and Bisphenol-A Exposure During Adolescent Development: A Golgi Study

Exposure to Bisphenol A (BPA) is inevitable because it is found in compounds we are exposed to daily, such as plastics, epoxy, and flame retardant materials. BPA is a known endocrine disruptor that interacts with estrogen and can affect both neuronal development and behavior. Previous studies, done on adult rats, have demonstrated that estrogen increases and BPA decreases spine density in the hippocampus. In the present study we investigated the effects of BPA administration during adolescence on spine density in the hippocampus of female rats at two time points. Female ovariectomized rats (6/group) were injected with BPA, estrogen, or oil during adolescence (postnatal days 42-49) and sacrificed at day 49 (Group 1) or day 79 (Group 2). Brains were removed and processed for Golgi impregnation and dendritic spine density was assessed in CA1 pyramidal cells and granule cells of the hippocampus. Given that adolescent brains are still developing and more vulnerable to outside stimuli, we hypothesize that BPA will have profound effects on dendritic spine density in the hippocampus. In addition the results of the present study will allow for a direct comparison of BPA and estrogen effects on dendritic spine density in adolescent and adult brains

Artists have superior local and global processing abilities but show a preference for initially drawing globally

The attentional demands of drawing require both local processing of an object’s details and global processing of its overall structure. In this study, we examined the extent to which artists have superior local and global processing skills, how these skills relate to artists’ ability to draw realistically and to autistic-related traits, and whether artists initially take a local or global approach to drawing. Forty first-year college art students and 41 nonart students completed two tasks assessing local processing and two tasks assessing global processing. Participants completed two drawing tasks that assessed their ability to draw realistically, two copying tasks that assessed whether they showed a preference for initially copying the local or global aspects of an object, and the Autism-Spectrum Quotient that assessed autistic-related traits. We found that art students outperformed nonart students on both the local and global processing tasks and that drawing ability was related to performance on these tasks. We also found that art students were more likely than nonart students to initially copy the global features in their drawings. Finally, we found that art students did not exhibit more autistic-related traits than nonart students and that the number of autistic-related traits was unrelated to performance on the local and global processing, drawing, or copying tasks. These results suggest that art students have an attentional flexibility that allows them to process information at a local and global level but that they have a preference for initially drawing globally

Omnipolar EGM Voltage Mapping for Atrial Fibrosis Identification Evaluated with an Electrophysiological Model

[EN] Atrial fibrillation (AF) is the most spread heart arrhythmia, whose mechanisms are not completely clear yet. Catheter ablation is a standard treatment, which isolates the area involved in the arrhythmia. Intracardiac electrograms (EGMs) are used to better understand the AF mechanisms and to find appropriate ablation sites. Bipolar EGMs (b-EGMs) are often employed, but their amplitude and shape depend on catheter orientation, limiting reliability. To avoid this uncertainty, an approach insensitive to catheter orientation, referred as Omnipolar EGM (OP-EGM) method, has been introduced, which uses an estimation of the electric field within a group of electrodes, referred as clique. In this work, we compare different mapping approaches based on b-EGMs and OPEGM signals in simulation including fibrosis, so to evaluate their ability to detect fibrosis and reproduce the spatial distribution of the voltage. Maps have been computed using two clique configurations (square and triangular), introducing or not a previous time alignment of the bEGMs. OP-EGM signals have been obtained by projecting the electric field along directions of its maximal excursion and its principal components. Results show that both cliques configurations present good performance, in terms of fibrosis detection and correlation with the reference voltage maps. In addition, the proposed alignment of b-EGMS improves maps based on OP-EGM signals, especially when square cliques are used.This work is part of a project that has received funding from the European Union¿s Horizon 2020 research and innovation program under the Marie Sk¿odowska-Curie grant agreement No 766082 (MY-ATRIA).Riccio, J.; Alcaine, A.; Rocher-Ventura, S.; Laguna, P.; Saiz Rodríguez, FJ.; Martínez, JP. (2021). Omnipolar EGM Voltage Mapping for Atrial Fibrosis Identification Evaluated with an Electrophysiological Model. IEEE. 920-924. https://doi.org/10.23919/Eusipco47968.2020.9287670S92092

Análisis de dispersión de autovalores de electrogramas unipolares para la detección de fibrosis auricular

La fibrosis auricular representa un papel clave en la patogenia de la fibrilación auricular, y es un factor importante para el guiado de procedimientos de ablación con catéter. Se consideran fibróticas las áreas cuyos electrogramas bipolares (b-EGMs) presentan una amplitud pico-a-pico inferior a 0.5 mV [1]. Sin embargo, la amplitud de dichas señales depende también de otros factores además de la fibrosis

Análisis de dispersión de autovalores de electrogramas unipolares para la detección de fibrosis auricular

La fibrosis auricular representa un papel clave en la patogenia de la fibrilación auricular, y es un factor importante para el guiado de procedimientos de ablación con catéter. Se consideran fibróticas las áreas cuyos electrogramas bipolares (b-EGMs) presentan una amplitud pico-a-pico inferior a 0.5 mV [1]. Sin embargo, la amplitud de dichas señales depende también de otros factores además de la fibrosis

Unipolar Electrogram Eigenvalue Distribution Analysis for the Identification of Atrial Fibrosis

[EN] Atrial fibrosis plays an important role in the pathogenesis of atrial fibrillation (AF). Low bipolar electrograms (b-EGMs) peak-to-peak voltage areas indicate scar tissue and are considered targets for AF substrate ablation. However, this approach ignores the spatiotemporal information embedded in the signal and the dependence of b-EGMs on catheter orientation. This work proposes an approach to detect fibrosis based on the eigenvalue dominance ratio (EIGDR) in an ensemble (clique) of unipolar electrograms (u-EGMs). A 2-D tissue with a central circular patch of fibrosis has been simulated using the Courtemanche cellular model. Maps of EIGDR have been computed using two sizes of electrode cliques, from the original u-EGMs within the ensemble or after a time alignment of these signals. Performance of each map in detecting fibrosis has been evaluated using receiver operating characteristic curves and detection accuracy. Best results achieve an area under the curve (AUC) of 0.98 and an accuracy (ACC) of 1 when we use as marker the gain in eigenvalue dominance produced by the ensemble alignmentFunding comes from EU Programme H2020 under the Marie Sklodowska-Curie Grant No 766082 (MY-ATRIA), Gobierno de Aragon (BSICoS Group T39-20R) cofunded by FEDER 2014-2020 "Building Europe from Aragon", fellowship ACIF/2018/174 from Generalitat Valenciana, and PID2019-104881RB-I00 from MICINN, SpainRiccio, J.; Rocher-Ventura, S.; Martínez-Mateu, L.; Alcaine, A.; Saiz Rodríguez, FJ.; Martínez, JP.; Laguna, P. (2020). Unipolar Electrogram Eigenvalue Distribution Analysis for the Identification of Atrial Fibrosis. IEEE. 1-4. https://doi.org/10.22489/CinC.2020.434S1

Atrial fibrosis identification with unipolar electrogram eigenvalue distribution analysis in multi-electrode arrays

Atrial fbrosis plays a key role in the initiation and progression of atrial fbrillation (AF). Atrial fbrosis is typically identifed by a peak-to-peak amplitude of bipolar electrograms (b-EGMs) lower than 0.5 mV, which may be considered as ablation targets. Nevertheless, this approach disregards signal spatiotemporal information and b-EGM sensitivity to catheter orientation. To overcome these limitations, we propose the dominant-to-remaining eigenvalue dominance ratio (EIGDR) of unipolar electrograms (u-EGMs) within neighbor electrode cliques as a waveform dispersion measure, hypothesizing that it is correlated with the presence of fbrosis. A simulated 2D tissue with a fbrosis patch was used for validation. We computed EIGDR maps from both original and time-aligned u-EGMs, denoted as R and RA, respectively, also mapping the gain in eigenvalue concentration obtained by the alignment, ΔRA. The performance of each map in detecting fbrosis was evaluated in scenarios including noise and variable electrode-tissue distance. Best results were achieved by RA, reaching 94% detection accuracy, versus the 86% of b-EGMs voltage maps. The proposed strategy was also tested in real u-EGMs from fbrotic and non-fbrotic areas over 3D electroanatomical maps, supporting the ability of the EIGDRs as fbrosis markers, encouraging further studies to confrm their translation to clinical settings

Characterization of Atrial Propagation Patterns and Fibrotic Substrate With a Modified Omnipolar Electrogram Strategy in Multi-Electrode Arrays

[EN] Introduction: The omnipolar electrogram method was recently proposed to try to generate orientation-independent electrograms. It estimates the electric field from the bipolar electrograms of a clique, under the assumption of locally plane and homogeneous propagation. The local electric field evolution over time describes a loop trajectory from which omnipolar signals in the propagation direction, substrate and propagation features, are derived. In this work, we propose substrate and conduction velocity mapping modalities based on a modified version of the omnipolar electrogram method, which aims to reduce orientation-dependent residual components in the standard approach. Methods: A simulated electrical propagation in 2D, with a tissue including a circular patch of diffuse fibrosis, was used for validation. Unipolar electrograms were calculated in a multi-electrode array, also deriving bipolar electrograms along the two main directions of the grid. Simulated bipolar electrograms were also contaminated with real noise, to assess the robustness of the mapping strategies against noise. The performance of the maps in identifying fibrosis and in reproducing unipolar reference voltage maps was evaluated. Bipolar voltage maps were also considered for performance comparison. Results: Results show that the modified omnipolar mapping strategies are more accurate and robust against noise than bipolar and standard omnipolar maps in fibrosis detection (accuracies higher than 85 vs. 80% and 70%, respectively). They present better correlation with unipolar reference voltage maps than bipolar and original omnipolar maps (Pearson's correlations higher than 0.75 vs. 0.60 and 0.70, respectively). Conclusion: The modified omnipolar method improves fibrosis detection, characterization of substrate and propagation, also reducing the residual sensitivity to directionality over the standard approach and improving robustness against noise. Nevertheless, studies with real electrograms will elucidate its impact in catheter ablation interventions.This study has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 766082 (MY-ATRIA project), from projects PID2019-104881RB-I00, and PID2019-105674RB-I00 from MICINN, Spain, from Gobierno de Aragon (BSICoS Group T39-20R) cofunded by FEDER 20142020 Building Europe from Aragon and from Generalitat Valenciana through the fellowship ACIF/2018/174 and the grant PROMETEO/2020/043.Riccio, J.; Alcaine, A.; Rocher-Ventura, S.; Martínez-Mateu, L.; Laranjo, S.; Saiz Rodríguez, FJ.; Laguna, P.... (2021). Characterization of Atrial Propagation Patterns and Fibrotic Substrate With a Modified Omnipolar Electrogram Strategy in Multi-Electrode Arrays. Frontiers in Physiology. 12:1-21. https://doi.org/10.3389/fphys.2021.674223S1211

The Lantern Vol. 52, No. 1, Fall 1985

• Nudes • Orion • Fragments of an Epic • Sunrise • The Planting Season • Nursing Home • Hope Chest • Childhood Swing • Relationships • Elroy, Leopold, and Max • Urban Dragon • The Farmer\u27s Wife • A Ballad of Two Lovers • Betrayal • Choices • Letting Go • Emergence of a Butterfly • Poem for Every Man • Friction • Genesis • All\u27s Well • The Willow Tree • White Wasteland • Moe\u27s Happy Christmas • Rare Bird • Carnivalhttps://digitalcommons.ursinus.edu/lantern/1127/thumbnail.jp