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Neurovascular unit on a chip:the relevance and maturity as an advanced in vitro model

Neural Regeneration Research 2024年第6期19卷 1165-1166页

作者： Sujey Palma-Florez Anna Lagunas Mònica Mir Nanobioengineering Group Institute for Bioengineering of Catalonia(IBEC)Barcelona Institute of Science and Technology(BIST)BarcelonaSpain CIBER-BBN ISCIIIMadridSpain Department of Electronics and Biomedical Engineering University of BarcelonaBarcelonaSpain

The brain is a high-energy demanding organ,consuming around 20%of the metabolic energy *** fulfill this demand,cerebral blood flow(CBF)supplies oxygen and glucose continuously through the intricate network of cerebral blood *** for many years brain activity and blood flow were conceived as independent processes,MRI-based functional brain imaging demonstrated that there is a coupling between them.

关键词： cerebral maturity consuming

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Dependence of Atrial Fibrillatory Rate Variations Induced by Head-Up/Down Tilt-Test on Autonomic Action 50

Dependence of Atrial Fibrillatory Rate Variations Induced by...

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50th Computing in Cardiology, CinC 2023

作者： Celotto, Chiara Sanchez, Carlos Abdollahpur, Mostafa Sandberg, Frida Laguna, Pablo Pueyo, Esther Aragon Institute of Engineering Research University of Zaragoza Iis Aragón Zaragoza Spain Ciber in Bioengineering Biomaterials and Nanomedicine Zaragoza Spain University of Lund Lund Sweden

ISBN: (纸本)9798350382525

In atrial fibrillation (AF), autonomic nervous system (ANS) differences among individuals may have a substantial influence on the varying effectiveness of anti-AF treatments. This work aimed to assess the relationship between changes in autonomic balance and in atrial fibrillatory rate (AFR) oscillations (F_{mathrm{f}}(t)) induced by head-up (HUT) and head-down (HDT) tilt test. 22 persistent AF (psAF) patients underwent a tilt test protocol and ECGs were recorded and analyzed to extract F_{mathrm{f}}(t) and its respiratory modulation (Delta F_{mathrm{f}}). Electrophysiological simulations of stable reentrant rotors in 2D human atrial psAF tissues were performed. Combinations of different levels of parasympathetic stimulation (PSS) by acetylcholine (ACh) and sympathetic stimulation (SS) by isoproterenol (Iso) were tested. The respiratory-related modulation of ACh was modeled by a cyclic temporal variation of ACh. In the patients, HUT/HDT resulted in an increase/decrease in AFR with respect to baseline (BL). Variations in Delta F_{mathrm{f}} from HDT/HUT to BL/HDT were significantly positively correlated with the variations in mean F_{mathrm{f}}(t)(overline{F}_{mathrm{f}}). In the simulations, higher Iso and/or ACh led to an increase in overline{F}_{mathrm{f}}, while Delta F_{mathrm{f}} was correlated to the range of ACh variation. HUT/HDT increased/decreased AFR, which could be explained by an increase/reduction in SS. The concomitant variation in Delta F_{mathrm{f}} could be linked to changes in PSS. © 2023 CinC.

关键词： Electrophysiology

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Evaluation of a QT Adaptation Time Estimator for ECG Exercise Stress Test in Controlled Simulation 50

Evaluation of a QT Adaptation Time Estimator for ECG Exercis...

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50th Computing in Cardiology, CinC 2023

作者： Perez, Cristina Pueyo, Esther Martinez, Juan Pablo Sornmo, Leif Laguna, Pablo University of Zaragoza I3A Iis Aragón BSICoS Group Zaragoza Spain CIBER-Bioengineering Madrid Spain Lund University Department of Biomedical Engineering Sweden

ISBN: (纸本)9798350382525

Slowed adaptation of the QT interval to sudden abrupt heart rate (HR) changes has been identified as a marker of ventricular arrhythmic risk. However, abrupt HR changes are difficult to induce in patients. Quantifying the QT adaptation time in gradual HR changes, as observed in ECGs recording during an exercise stress test, has been recently proposed. The time lag between the QT series and an instantaneous memoryless HR-dependent QT series along stress test was computed as QT memory. Here, this method was evaluated in a control scenario using simulated exercise stress test ECG signals presenting different QT adaptation times. The method robustness was studied by contaminating the ECGs with muscular noise (MN) signals with different Signal-to-Noise ratio (SNR) values, either synthetic or extracted from real recordings. We found that delineation of the T-wave end point in the first transformed lead from Periodic Component Analysis offers the best performance for low SNR. Moreover, we confirmed that the estimator provides an unbiased estimate of the QT memory introduced in the simulations for the studied range of SNR values (25 to 50 dB). © 2023 CinC.

关键词： Electrocardiograms

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Rotor Termination in Cholinergic Paroxysmal Atrial Fibrillation by Small-Conductance Calcium-Activated K+Channels Inhibition and Isoproterenol: A Computational Study

Rotor Termination in Cholinergic Paroxysmal Atrial Fibrillat...

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2021 Computing in Cardiology, CinC 2021

作者： Celotto, Chiara Sanchez, Carlos Mountris, Konstantinos A. Laguna, Pablo Pueyo, Esther University of Zaragoza Zaragoza Spain CIBER in Bioengineering Biomaterials and Nanomedicine Zaragoza Spain

ISBN: (纸本)9781665479165

Hyperactivity of the parasympathetic nervous system has been linked to the onset of paroxysmal atrial fibrillation (AF). Recent investigations have proven inhibition of small-conductance calcium-activated potassium (SK) channels to improve adverse cholinergic effects in the atria. It has also been reported that beta -adrenergic stimulation by Isoproterenol (Iso) can act as a brake to lessen cholinergic effects on atrial tissue. Furthermore, the combination of SK channel block (SKb) and Iso has been suggested to possibly prolong atrial APD in ACh-stimulated myocytes. In this study, computational modeling was used to test individual and combined effects of SKb and Iso in terminating a stable rotor in a cholinergic AF model of human atria. 2D tissues with uniform ACh concentrations of 0.01 or 0.1mu M were simulated. After stable rotors were initiated, 1mu M Iso and/or complete SKb were progressively applied over time following different application kinetics. Both Iso alone and the combination of Iso and SKb were able to terminate rotors for the two ACh concentrations. SKb was only able to terminate the rotor for the lower ACh concentration. In conclusion, the results from this study support beta -adrenergic stimulation and SK channel block, the latter with less efficacy, as potential options to terminate rotors in parasympathetically-stimulated human atria. © 2021 Creative Commons.

关键词： Cardiology

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Nanowires replace lost retinal cells

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Science (New York, N.Y.) 2025年第6751期388卷 1025-1026页

作者： Eduardo Fernández Bioengineering Institute and Cátedra Bidons Egara University Miguel Hernández Elche Spain. CIBER Research Center on Bioengineering Biomaterials and Nanomedicine (CIBER BBN) Madrid Spain. John Moran Eye Center University of Utah Salt Lake City UT USA. Radboud University Donders Centre for Neuroscience Nijmegen Netherlands.

Tellurium nanowire networks could open up new avenues for artificial vision.

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Physiological Variations in CX43 and Fibrosis Deposition Affect Human Ventricular Electrophysiology Promoting Arrhythmia 50

Physiological Variations in CX43 and Fibrosis Deposition Aff...

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50th Computing in Cardiology, CinC 2023

作者： Garcia-Mendivil, Laura Perez-Zabalza, Maria Rosales, Ricardo M Vallejo-Gil, Jose M Fananas-Mastral, Javier Vazquez-Sancho, Manuel Bellido-Morales, Javier A Vaca-Nunez, Alexander S Ballester-Cuenca, Carlos Ordovas, Laura Pueyo, Esther Aragon Institute of Engineering Research University of Zaragoza Iis Aragón Zaragoza Spain Zaragoza Spain Ciber in Bioengineering Biomaterials and Nanomedicine Zaragoza Spain University Hospital Miguel Servet Department of Cardiovascular Surgery Zaragoza Spain Zaragoza Spain

ISBN: (纸本)9798350382525

Connexin 43 (Cx43), the major component of gap junctions in the ventricle, is responsible for electrical impulse transmission between ventricular cardiomyocytes. Little is known about the interindividual heterogeneity of CX43 tissue expression in the human left ventricle (LV) and its contribution to arrhythmogenecity either alone or in combination with other proarrhythmic factors like fibrosis. We processed LV fluorescent immunostaining images from living donors and characterized the population heterogeneity of CX43 expression and fibrosis deposition. The lowest CX43 expression and the highest fibrosis deposition values in the population were implemented in 2D computational models of human LV electrophysiology. We measured conduction velocity (CV) and areas of High Repolarization Gradient (HRG) from the simulated action potentials (APs), and the amplitude, duration and area of calculated unipolar electrograms (EGMs). Simulations showed that both reduced CX43 and fibrosis notably influence CV, HRG extent, EGM activation area and the dispersion of activation recovery intervals from EGMs, with a largest impact of CX43 reduction. In conclusion, decreased CX43 and increased fibrosis, to the extents measured in non-diseased human LV tissues, contribute to a substrate for the generation of reentrant arrhythmias, which can be quantified from ventricular EGMs. © 2023 CinC.

关键词： Electrophysiology

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Automatic characterization of Meibomian gland morphology

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ACTA OPHTHALMOLOGICA 2024年第Sup279期102卷

作者： Novo-Diez, Andrea Blanco-Vazquez, Marta Arlanzon-Lope, Pablo Valencia-Sandonis, Cristina Gonzalez-Garcia, Maria J. Fernandez, Itziar IOBA (Institute of Applied Ophthalmobiology) University of Valladolid Valladolid Spain CIBER-BBN (Biomedical Research Networking center in Bioengineering Biomaterials and Nanomedicine) Madrid Spain

Aims/Purpose: To characterize the Meibomian gland (MG) morphology in healthy subjects with an automatic software. Methods: An automatic software was developed for image analysis in R code, consisting of 4 stages: (1) selection of the region of interest, (2) image preprocessing to obtain a binary and a skeleton image, (3) modelling of each MG to fit each MG to a piecewise linear model, and (4) quantification of the following MG features: tortuosity, MG shortening, number of MGs, deviation from a vertical line, and MG area. Meibography images of the upper eyelid were acquired using the Easy Tear View+®. A group of 156 healthy subjects were included, with a mean age and confidence interval (CI) of 43.88 (95% CI: 41.38–46.37) years, range 16–76 years. Reference intervals (RI) were calculated for each MG feature to be used as a diagnostic tool to classify a specific value as normal or non-normal. Generalized Additive Models for Location, Scale and Shape were used to estimate the percentile curve for each morphologic feature of MG, considering the influence of age and sex. Results: Age had an influence on tortuosity, mean = 0.3 (95% CI: 0.3–0.31), RI: 0.19–0.4 <20 years, and 0.24–0.39 at 50–60 years. Age and sex had an influence in the MG shortening, mean = 63% (95% CI: 62–64%), mean RI: 58–74% <20 years; 59–84% >75 years; women RI: 56–71% <20 years; 57–82% >75 years. The rest of the variables were not affected by age or sex: number of MGs = 16.05 (95% CI: 15.28–16.82), RI: 8–27; vertical deviation = 0.37 (95% CI: 0.36–0.38), RI: 0.29–0.45, and MG area = 14% (95% CI: 14–15%), RI: 8.17–19.81%. Conclusions: Tortuosity variability decreases between 45 and 60 years of age. The MG shortening increases with age and is higher in men. These values could be useful to classify a meibography image as normal or non-normal, helping to diagnose MG alterations in an objective way.

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Effectiveness of Support Programmes for (in)Formal Caregivers of Older Dependent People to Design Technologies 9th

Effectiveness of Support Programmes for (in)Formal Caregiver...

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9th International Conference on Human Aspects of IT for the Aged Population, ITAP 2023, held as part of the 25th International Conference on Human-Computer Interaction, HCII 2023

作者： Zorrilla-Muñoz, Vanessa Veira-Ramos, Alberto Agulló-Tomás, María Silveria Garcia-Aracil, Nicolas Fernandez, Eduardo Bioengineering Institute Miguel Hernández University of Elche Elche Spain University Institute on Gender Studies University Carlos III of Madrid Getafe Spain Department of Social Analysis University Carlos III of Madrid Getafe Spain CIBER BBN Elche Spain

ISBN: (纸本)9783031349164

The growing number of older dependent population in Spain has incremented the demand for programmes and services aimed to provide support to (in)formal caregivers. Current legislation does not provide clear standardized practices for the results evaluation of such programmes which can constitute a guideline for public or private organizations, including NGOs. One strategy to successfully cope with this situation is the implementation of self-administrated questionnaires as an essential part of a cycle of continuous improvement of programmes and services. This paper is based on results from survey data collected from a sample of managers of programmes, suggests that entities using self-administrated questionnaires can, indeed, improve the effectiveness of their programmes significantly. The result of this study could contribute to the design and develop devices and software to improve care of older people and provide caregivers complementary assistance, especially, for older women. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

关键词： Computer programming

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Evaluation of a QT Adaptation Time Estimator for ECG Exercise Stress Test in Controlled Simulation

Evaluation of a QT Adaptation Time Estimator for ECG Exercis...

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Computers in Cardiology (CinC)

作者： Cristina Pérez Esther Pueyo Juan Pablo Martínez Leif Sörnmo Pablo Laguna BSICoS Group I3A IIS Aragón University of Zaragoza Zaragoza Spain CIBER-Bioengineering Biomaterials and Nanomedicine (CIBER BBN) Madrid Spain Department of Biomedical Engineering Lund University Sweden

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Effects of Acetylcholine Release Spatial Distribution on the Frequency of Atrial Reentrant Circuits: a Computational Study

Effects of Acetylcholine Release Spatial Distribution on the...

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2022 Computing in Cardiology, CinC 2022

作者： Celotto, Chiara Sanchez, Carlos Abdollahpur, Mostafa Sandberg, Frida Rodriguez, Jose F. Laguna, Pablo Pueyo, Esther Aragon Institute of Engineering Research University of Zaragoza Iis Aragón Zaragoza Spain Ciber in Bioengineering Biomaterials and Nanomedicine Zaragoza Spain University of Lund Lund Sweden Politecnico di Milano Milano Italy

ISBN: (纸本)9798350300970

The frequency of the ECG fibrillatory f-waves (Ff) in atrial fibrillation (AF) shows significant variations over time. Cardiorespiratory interactions through the autonomic nervous system have been suggested to play a role in such variations. Here, we tested whether the spatial distribution associated with the release of the parasympathetic neurotransmitter acetylcholine (ACh) could affect the frequency of atrial reentrant circuits. Computational simulations in a human persistent-AF 3D atrial model were performed. We evaluated two different patterns of atrial innervation: ACh release restricted to the area of the ganglionated plexi (GP) and the nerves departing from them, following the so-called octopus hypothesis, and ACh release distributed uniformly randomly throughout the atria. In both cases, ACh release sites occupied 8% of the atria. The temporal pattern of ACh release was simulated following a sinusoidal waveform of frequency 0.125 Hz (respiratory frequency). Different mean levels and peak-to-peak variation ranges of ACh were tested. We found that variations in the dominant frequency Ff followed the simulated temporal ACh pattern in all cases, with Ff modulation being more pronounced for increasingly larger ACh variation ranges. For the tested percentage of ACh release sites (8%), the spatial distribution of ACh did not have an impact on Ff modulation. © 2022 Creative Commons.

关键词： Spatial distribution

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