Updated Toolbox for Assessing Neuronal Network Reconstruction after Cell Therapy.

Cell therapy has proven to be a promising treatment for a range of neurological disorders, including Parkinson Disease, drug-resistant epilepsy, and stroke, by restoring function after brain damage. Nevertheless, evaluating the true effectiveness of these therapeutic interventions requires a deep understanding of the functional integration of grafted cells into existing neural networks. This review explores a powerful arsenal of molecular techniques revolutionizing our ability to unveil functional integration of grafted cells within the host brain. From precise manipulation of neuronal activity to pinpoint the functional contribution of transplanted cells by using opto- and chemo-genetics, to real-time monitoring of neuronal dynamics shedding light on functional connectivity within the reconstructed circuits by using genetically encoded (calcium) indicators in vivo. Finally, structural reconstruction and mapping communication pathways between grafted and host neurons can be achieved by monosynaptic tracing with viral vectors. The cutting-edge toolbox presented here holds immense promise for elucidating the impact of cell therapy on neural circuitry and guiding the development of more effective treatments for neurological disorders.

Neuronal activity dynamics in the dentate gyrus during early epileptogenesis.

Epileptogenesis is a complex process involving a multitude of changes at the molecular, cellular and network level. Previous studies have identified several key alterations contributing to epileptogenesis and the development of hyper-excitability in different animal models, but only a few have focused on the early stages of this process. For post status epilepticus (SE) temporal lobe epilepsy in particular, understanding network dynamics during the early phases might be crucial for developing accurate preventive treatments to block the development of chronic spontaneous seizures. In this study, we used a viral vector mediated approach to examine activity of neurons in the dentate gyrus of the hippocampus during early epileptogenesis. We find that while granule cells are active 8 h after SE and then gradually decrease their activity, Calretinin-positive mossy cells and Neuropeptide Y-positive GABAergic interneurons in the hilus show a delayed activation pattern starting at 24 and peaking at 48 h after SE. These data suggest that indirect inhibition of granule cells by mossy cells through recruitment of local GABAergic interneurons could be an important mechanisms of excitability control during early epileptogenesis, and contribute to our understanding of the complex role of these cells in normal and pathological conditions.

Does Sex Matter to the Biomedical Approach in Clinical Practice Guidelines (CPGs)?: A Systematic Review of Methodology Documents Used in the Spanish National Health System.

Sex and gender are important variables in health, although their incorporation in medicine has been very slow. If research is sensitive and yields fruitful sex and gender evidence, these results should be included in the guidelines for clinical practices. However, literature claims that clinical practice guidelines devote very little space to these categories. The present systematic review addresses the relevance of sex and gender dimensions through methodology documents for the development of clinical practice guidelines based on three sources: the AGREE Reporting Checklist, the GRADE Handbook, and the Spanish GuíaSalud NHS Clinical Guideline Program. Findings suggest that neglecting sex and gender issues in the biomedical approach may lead to continuing to ignore relevant evidence on biological and social dimensions that do indeed influence people's health and diseases.

Transplantation of Human Stem Cell-Derived GABAergic Neurons into the Early Postnatal Mouse Hippocampus to Mitigate Neurodevelopmental Disorders.

A reduced number or dysfunction of inhibitory interneurons is a common contributor to neurodevelopmental disorders. Therefore, cell therapy using interneurons to replace or mitigate the effects of altered neuronal circuits is an attractive therapeutic avenue. To this end, more knowledge is needed about how human stem cell-derived GABAergic interneuron-like cells (hdINs) mature, integrate, and function over time in the host circuitry. Of particular importance in neurodevelopmental disorders is a better understanding of whether these processes in transplanted cells are affected by an evolving and maturing host brain. The present protocol describes a fast and highly efficient generation of hdINs from human embryonic stem cells based on the transgenic expression of the transcription factors Ascl1 and Dlx2. These neuronal precursors are transplanted unilaterally, after 7 days in vitro, to the hippocampus of neonatal 2-day-old mice. The transplanted neurons disperse in the ipsi- and contralateral hippocampus of a mouse model of cortical dysplasia-focal epilepsy syndrome and survive for up to 9 months after transplantation. This approach allows for investigating the cellular identity, integration, functionality, and therapeutic potential of transplanted interneurons over an extended time in developing healthy and diseased brains.

Work-Life Balance and Teleworking: Lessons Learned during the Pandemic on Gender Role Transformation and Self-Reported Well-Being.

Lockdown during COVID-19 forced the emergence of a new scenario, with men and women teleworkers spending all their time at home. The purpose of this study is to address whether this situation has triggered a transformation in gender roles and self-reported well-being, comparing the responses of male and female respondents to the EUROFOUND April to July 2020 survey. The analysis addresses cultural differences across European regions related to diverse gender regimes, employment status, and the possibility of teleworking. It explores male and female well-being through life satisfaction, the distance between happiness and life satisfaction, and rates their feelings about work-life balance. Findings on life satisfaction display a low transformation of social roles, with women still worrying about work-life balance, while men were more affected by the health crisis. Men self-report high life satisfaction across Europe compared to women, although unexpectedly, female freelancers in Northern and Southern European had a higher life satisfaction ratio than men. Both men and women teleworkers reported difficulties with managing work-life balance at home, despite women handling core care and household tasks. These findings suggest that women would have received more support from men, as they worked harder and longer hours during the lockdown, despite their weak position in the labor market. This would seem to be a propitious setting for men to have assumed more responsibility at home, resulting in a more equal distribution of roles at home.

Transcription factor-based direct conversion of human fibroblasts to functional astrocytes.

Astrocytes are emerging key players in neurological disorders. However, their role in disease etiology is poorly understood owing to inaccessibility of primary human astrocytes. Pluripotent stem cell-derived cells fail to mimic age and due to their clonal origin do not mimic genetic heterogeneity of patients. In contrast, direct conversion constitutes an attractive approach to generate human astrocytes that capture age and genetic diversity. We describe efficient direct conversion of human fibroblasts to functional induced astrocytes (iAs). Expression of the minimal combination Sox9 and Nfib generates iAs with molecular, phenotypic, and functional properties resembling primary human astrocytes. iAs could be obtained by conversion of fibroblasts covering the entire human lifespan. Importantly, iAs supported function of induced neurons obtained through direct conversion from the same fibroblast population. Fibroblast-derived iAs will become a useful tool to elucidate the biology of astrocytes and complement current in vitro models for studies of late-onset neurological disorders.

Human Stem Cell-Derived GABAergic Interneurons Establish Efferent Synapses onto Host Neurons in Rat Epileptic Hippocampus and Inhibit Spontaneous Recurrent Seizures.

Epilepsy is a complex disorder affecting the central nervous system and is characterised by spontaneously recurring seizures (SRSs). Epileptic patients undergo symptomatic pharmacological treatments, however, in 30% of cases, they are ineffective, mostly in patients with temporal lobe epilepsy. Therefore, there is a need for developing novel treatment strategies. Transplantation of cells releasing γ-aminobutyric acid (GABA) could be used to counteract the imbalance between excitation and inhibition within epileptic neuronal networks. We generated GABAergic interneuron precursors from human embryonic stem cells (hESCs) and grafted them in the hippocampi of rats developing chronic SRSs after kainic acid-induced status epilepticus. Using whole-cell patch-clamp recordings, we characterised the maturation of the grafted cells into functional GABAergic interneurons in the host brain, and we confirmed the presence of functional inhibitory synaptic connections from grafted cells onto the host neurons. Moreover, optogenetic stimulation of grafted hESC-derived interneurons reduced the rate of epileptiform discharges in vitro. We also observed decreased SRS frequency and total time spent in SRSs in these animals in vivo as compared to non-grafted controls. These data represent a proof-of-concept that hESC-derived GABAergic neurons can exert a therapeutic effect on epileptic animals presumably through establishing inhibitory synapses with host neurons.

Human stem cell-derived GABAergic neurons functionally integrate into human neuronal networks.

Gamma-aminobutyric acid (GABA)-releasing interneurons modulate neuronal network activity in the brain by inhibiting other neurons. The alteration or absence of these cells disrupts the balance between excitatory and inhibitory processes, leading to neurological disorders such as epilepsy. In this regard, cell-based therapy may be an alternative therapeutic approach. We generated light-sensitive human embryonic stem cell (hESC)-derived GABAergic interneurons (hdIN) and tested their functionality. After 35 days in vitro (DIV), hdINs showed electrophysiological properties and spontaneous synaptic currents comparable to mature neurons. In co-culture with human cortical neurons and after transplantation (AT) into human brain tissue resected from patients with drug-resistant epilepsy, light-activated channelrhodopsin-2 (ChR2) expressing hdINs induced postsynaptic currents in human neurons, strongly suggesting functional efferent synapse formation. These results provide a proof-of-concept that hESC-derived neurons can integrate and modulate the activity of a human host neuronal network. Therefore, this study supports the possibility of precise temporal control of network excitability by transplantation of light-sensitive interneurons.

Longitudinal Chromatic Aberration in Patients Implanted With Trifocal Diffractive Hydrophobic IOLs.

PURPOSE: To measure the in vivo longitudinal chromatic aberration (LCA) from the chromatic difference of focus (480 to 700 nm) using psychophysical methods in patients bilaterally implanted with a hydrophobic trifocal intraocular lens (IOL). METHODS: Psychophysical best focus was measured in both eyes at different wavelengths (480 to 700 nm) and at three different viewing distances (0.00, +1.75, and +3.50 diopters [D]) using a custom-developed polychromatic adaptive optics set-up provided with a supercontinuum laser, a Hartmann-Shack wavefront sensor, a deformable mirror, a motorized Badal system, a pupil monitoring system, and a psychophysical channel with monochromatically illuminated stimuli. Measurements were performed on 10 patients (20 eyes) bilaterally implanted with hydrophobic trifocal diffractive IOLs (FineVisionHP POD F GF; PhysIOL). LCA was computed from the chromatic difference of focus curves as the difference between 480 and 700 nm at near, intermediate, and far. RESULTS: The LCA from psychophysical measurements was significantly higher for far vision (0.99 ± 0.06 diopters [D]), than for intermediate (0.67 ± 0.10 D) and near (0.23 ± 0.08 D) vision (one-way analysis of variance, P < .05). CONCLUSIONS: LCA for far vision was significantly higher than for intermediate and near vision in hydrophobic trifocal diffractive IOLs, in agreement with a previous study with the same optical design but hydrophilic material IOLs. The LCA for the hydro-phobic IOL is slightly higher than for the hydrophilic IOL at far. Different combinations of refractive and diffractive LCA will allow optimizing IOL designs to improve polychromatic image quality. [J Refract Surg. 2020;36(12):804-810.].

Optical and Visual Quality With Physical and Visually Simulated Presbyopic Multifocal Contact Lenses.

Purpose: As multifocal contact lenses (MCLs) expand as a solution for presbyopia correction, a better understanding of their optical and visual performance becomes essential. Also, providing subjects with the experience of multifocal vision before contact lens fitting becomes critical, both to systematically test different multifocal designs and to optimize selection in the clinic. In this study, we evaluated the ability of a simultaneous vision visual simulator (SimVis) to represent MCLs. Methods: Through focus (TF) optical and visual quality with a center-near aspheric MCL (low, medium and high near adds) were measured using a multichannel polychromatic Adaptive Optics visual simulator equipped with double-pass, SimVis (temporal multiplexing), and psychophysical channels to allow measurements on-bench and in vivo. On bench TF optical quality of SimVis-simulated MCLs was obtained from double-pass (DP) images and images of an E-stimulus using artificial eyes. Ten presbyopic subjects were fitted with the MCL. Visual acuity (VA) and DP retinal images were measured TF in a 4.00 D range with the MCL on eye, and through SimVis simulations of the same MCLs on the same subjects. Results: TF optical (on bench and in vivo) and visual (in vivo) quality measurements captured the expected broadening of the curves with increasing add. Root mean square difference between real and SimVis-simulated lens was 0.031/0.025 (low add), 0.025/0.015 (medium add), 0.019/0.011 (high add), for TF DP and TF LogMAR VA, respectively. A shape similarity metric shows high statistical values (lag κ = 0), rho = 0.811/0.895 (low add), 0.792/0.944 (medium add), and 0.861/0.915 (high add) for TF DP/LogMAR VA, respectively. Conclusions: MCLs theoretically and effectively expand the depth of focus. A novel simulator, SimVis, captured the through-focus optical and visual performance of the MCL in most of the subjects. Visual simulators allow subjects to experience vision with multifocal lenses prior to testing them on-eye. Translational Relevance: Simultaneous visual simulators allow subjects to experience multifocal vision non-invasively. We demonstrated equivalency between real multifocal contact lenses and SimVis-simulated lenses. The results suggest that SimVis is a suitable technique to aid selection of presbyopic corrections in the contactology practice.

Interaction of Monochromatic and Chromatic Aberrations in Pseudophakic Patients.

PURPOSE: To measure monochromatic aberrations at various wavelengths in eyes implanted with the Clareon monofocal aspheric intraocular lens (IOL) (Alcon Laboratories, Inc., Fort Worth, TX). The authors estimated longitudinal chromatic aberration (LCA), modulation transfer functions (MTFs), and the impact of interactions between chromatic and monochromatic aberrations on retinal image quality. METHODS: Ten patients (age: 68.4 ± 3.21 years) were measured in two experiments: (1) Hartmann-Shack wave aberrations at five visible wavelengths (480 to 700 nm) and (2) best subjective focus at each wavelength. Objective and psychophysical LCAs were obtained from the Zernike defocus and psychophysical best focus, respectively. MTFs were calculated for the closest wavelengths to the peak sensitivity of the three cone classes (S [480 nm], M [555 nm], and L [564 nm]) using the measured aberrations and chromatic difference of focus. The degradation produced by LCA was estimated as the visual Strehl ratio for green divided by the visual Strehl ratio for blue and red. RESULTS: The root mean square for higher order aberrations (HOAs) ranged from 0.0622 to 0.2084 µm (700 nm, 4.3-mm pupil). Monochromatic visual Strehl ratio was above 0.35 in all patients. LCA was 1.23 ± 0.05 diopters (D) (psychophysical) and 0.90 ± 0.11 D (objective). Visual Strehl ratio decreased by a factor ranging from 1.38 to 3.82 on chromatic defocus from green to blue. There was a significant correlation between native visual Strehl ratio and the degradation produced by LCA (ie, visual Strehl555/visual Strehl480). CONCLUSIONS: The Clareon IOL compensates for spherical aberration, with postoperative wave aberrations dominated by astigmatism and other HOAs, being highly subject-dependent. The impact of LCA in blue is largely dependent on the magnitude of monochromatic aberrations. [J Refract Surg. 2020;36(4):230-238.].

VioBio lab adaptive optics: technology and applications by women vision scientists.

PURPOSE: Adaptive Optics allows measurement and manipulation of the optical aberrations of the eye. We review two Adaptive Optics set-ups implemented at the Visual Optics and Biophotonics Laboratory, and present examples of their use in better understanding of the role of optical aberrations on visual perception, in normal and treated eyes. RECENT FINDINGS: Two systems (AOI and AOII) are described that measure ocular aberrations with a Hartmann-Shack wavefront sensor, which operates in closed-loop with an electromagnetic deformable mirror, and visual stimuli are projected in a visual display for psychophysical measurements. AOI operates in infrared radiation (IR) light. AOII is provided with a supercontiniuum laser source (IR and visible wavelengths), additional elements for simulation (spatial light modulator, temporal multiplexing with optotunable lenses, phase plates, cuvette for intraocular lenses-IOLs), and a double-pass retinal camera. We review several studies undertaken with these AO systems, including the evaluation of the visual benefits of AO correction, vision with simulated multifocal IOLs (MIOLs), optical aberrations in pseudophakic eyes, chromatic aberrations and their visual impact, and neural adaptation to ocular aberrations. SUMMARY: Monochromatic and chromatic aberrations have been measured in normal and treated eyes. AO systems have allowed understanding the visual benefit of correcting aberrations in normal eyes and the adaptation of the visual system to the eye's native aberrations. Ocular corrections such as intraocular and contact lenses modify the wave aberrations. AO systems allow simulating vision with these corrections before they are implanted/fitted in the eye, or even before they are manufactured, revealing great potential for industry and the clinical practice. This review paper is part of a special issue of Ophthalmic & Physiological Optics on women in visual optics, and is co-authored by all women scientists of the research team.

Leaky Optoelectrical Fiber for Optogenetic Stimulation and Electrochemical Detection of Dopamine Exocytosis from Human Dopaminergic Neurons.

In Parkinson's disease, the degeneration of dopaminergic neurons in substantia nigra leads to a decrease in the physiological levels of dopamine in striatum. The existing dopaminergic therapies effectively alleviate the symptoms, albeit they do not revert the disease progression and result in significant adverse effects. Transplanting dopaminergic neurons derived from stem cells could restore dopamine levels without additional motor complications. However, the transplanted cells disperse in vivo and it is not possible to stimulate them on demand to modulate dopamine release to prevent dyskinesia. In order to address these issues, this paper presents a multifunctional leaky optoelectrical fiber for potential neuromodulation and as a cell substrate for application in combined optogenetic stem cell therapy. Pyrolytic carbon coated optical fibers are laser ablated to pattern micro-optical windows to permit light leakage over a large area. The pyrolytic carbon acts as an excellent electrode for the electrochemical detection of dopamine. Human neural stem cells are genetically modified to express the light sensitive opsin channelrhodopsin-2 and are differentiated into dopaminergic neurons on the leaky optoelectrical fiber. Finally, light leaking from the micro-optical windows is used to stimulate the dopaminergic neurons resulting in the release of dopamine that is detected in real-time using chronoamperometry.

Accelerated Researchers: Psychosocial Risks in Gendered Institutions in Academia.

In recent decades, scientific institutions have undergone significant changes due to new managerialism and the application of excellence in research. This research model has given rise to tensions related to increasing pressures and working demands in a competitive international environment that accelerate the pace of academic life. In addition, precarious working conditions and job insecurity have affected academics' lives and careers. Academic literature has already addressed these organizational changes and their impact on academics, however, few studies have focused on psychosocial risks related to time constraints, meritocratic pressures and career insecurity from a gender perspective. This analysis is relevant given the gendered distribution of responsibilities and the evidence of gender biases in academia that hinder the advancement of gender equality in scientific institutions, as the persistent lack of women at the top of research careers show. In this paper, we explore the psychosocial effects of the new organizational model of science characterized by accelerated time regimes and precarious working conditions from a gender perspective. We draw attention to gender-based discriminatory practices that may yield an accumulative effect on the well-being of women academics. We analyze 36 interviews from women and men researchers from five areas of knowledge in Spanish universities and research centers, following a 'gendered institutions' approach. The results highlight psychosocial risks for both men and women academics as a result of accelerated work organizations, intensified by uncertainty and hyper-competition due to lack of positions. The hegemonic male work model characterized by total availability confirms academia as a gendered institution, especially damaging women's well-being and careers, as well as those of men committed to care responsibilities - challenging motherhood explanations - which may discourage them from the pursuit of gender equality. Our findings highlight discriminatory practices toward women academics which create psychological harm and feelings of being unwelcome, putting their career progression at risk. Lastly, we suggest a different model of work organization following the implementation of a culture based on an 'ethics of care' feminist approach.

In Vivo Measurement of Longitudinal Chromatic Aberration in Patients Implanted With Trifocal Diffractive Intraocular Lenses.

PURPOSE: To measure the longitudinal chromatic aberration (LCA) by both psychophysical methods and in vivo double-pass retinal imaging in patients bilaterally implanted with trifocal diffractive intraocular lenses (IOLs). METHODS: Measurements were performed with a polychromatic adaptive optics system provided with a supercontinuum laser, a Hartmann-Shack wavefront sensor, a deformable mirror, a motorized Badal system, a pupil monitoring system, a double-pass retinal imaging channel, and a psychophysical channel with monochromatically illuminated stimuli. Ten patients (20 eyes) bilaterally implanted with hydrophilic trifocal diffractive IOLs (POD F [FINeVision]; PhysIOL, Liege, Belgium) participated in the study. Measurements were performed in both eyes at three different viewing distances (0.00, +1.75, and +3.50 diopters [D]). Subjective best focus of monochromatic stimuli at five wavelengths (480 to 700 nm) was obtained using the Badal system. Best focused images of through-focus double-pass image series were obtained at three wavelengths (480 to 700 nm). LCA was computed from chromatic difference of focus curves (objective and subjective) as the difference between 480 and 700 nm at near, intermediate, and far. RESULTS: The average subjective LCA was 0.82 ± 0.05 D for far, 0.27 ± 0.15 D for intermediate, and 0.15 ± 0.15 D for near. The average objective LCA was 0.72 ± 0.10 D for far, 0.19 ± 0.15 D for intermediate, and 0.07 ± 0.17 D for near. CONCLUSIONS: Objective LCA was lower than subjective LCA, which was in agreement with previous studies on patients with phakic and monofocal IOLs. In vivo measurements of LCA enable understanding of the relative contribution of refractive and diffractive LCA and will eventually optimize IOL designs to improve polychromatic image quality. [J Refract Surg. 2017;33(11):736-742.].

Stroke alters behavior of human skin-derived neural progenitors after transplantation adjacent to neurogenic area in rat brain.

BACKGROUND: Intracerebral transplantation of human induced pluripotent stem cells (iPSCs) can ameliorate behavioral deficits in animal models of stroke. How the ischemic lesion affects the survival of the transplanted cells, their proliferation, migration, differentiation, and function is only partly understood. METHODS: Here we have assessed the influence of the stroke-induced injury on grafts of human skin iPSCs-derived long-term neuroepithelial-like stem cells using transplantation into the rostral migratory stream (RMS), adjacent to the neurogenic subventricular zone, in adult rats as a model system. RESULTS: We show that the occurrence of an ischemic lesion, induced by middle cerebral artery occlusion, in the striatum close to the transplant does not alter the survival, proliferation, or generation of neuroblasts or mature neurons or astrocytes from the grafted progenitors. In contrast, the migration and axonal projection patterns of the transplanted cells are markedly influenced. In the intact brain, the grafted cells send many fibers to the main olfactory bulb through the RMS and a few of them migrate in the same direction, reaching the first one third of this pathway. In the stroke-injured brain, on the other hand, the grafted cells only migrate toward the ischemic lesion and virtually no axonal outgrowth is observed in the RMS. CONCLUSIONS: Our findings indicate that signals released from the stroke-injured area regulate the migration of and fiber outgrowth from grafted human skin-derived neural progenitors and overcome the influence on these cellular properties exerted by the neurogenic area/RMS in the intact brain.

[Costs in hand amputations derived from labor injuries]. / Costos directos e indirectos por amputaciones en mano derivadas de accidentes de trabajo.

BACKGROUND: Hand injuries by labor accidents are first rank. It is necessary to have a multidisciplinary medical approach to frequently generated temporary and permanent disabilities that affect costs to an institution and to enterprise. OBJECTIVE: To determine the direct cost (DC) and the indirect cost (IC) of complete and partial amputations in hand caused by labor injuries. METHODS: An observational study was performed. The data was obtained from labor injuries with amputation of a finger or hand that received multidisciplinary management. The costs were calculated according to the list of Institutional Unit Costs. The IC were obtained with the "safety pays" program. RESULTS: We included 48 cases. The average age was 32.17 years; the cost of surgical operations was $767,470; and the payment of a partial disability permanent was $1,032,670; the DC of the sample of 48 workers was $2,955,007 with an IC of $3,250,507 and a total cost of $6,205,515, the average cost per worker of $51,741 for DC, $56,915 for IC and $108,657 for the total cost. CONCLUSIONS: Costs of hand injures requires the creation of prevention programs.