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person:Hiroshi Ishikawa (ishikh01) or chanc12 or shohas01 or chakrs07 or cohene10

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428


Illuminating Neural Computation Using Precision Optogenetics-Controlled Synthetic Perception

Gill, J V; Lerman, G M; Chong, E; Rinberg, D; Shoham, S
Connecting neuronal activity to perception requires tools that can probe neural codes at cellular and circuit levels, paired with sensitive behavioral measures. In this chapter, we present an overview of current methods for connecting neural codes to perception using precision optogenetics and psychophysical measurements of synthetically induced percepts. We also highlight new methodologies for validating precise control of optical and behavioral manipulations. Finally, we provide a perspective on upcoming developments that are poised to advance the field.
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EMBASE:640500153
ISSN: 1940-6045
CID: 5512082

Single cell RNA-seq of human cornea organoids identifies cell fates of a developing immature cornea

Maiti, George; Monteiro de Barros, Maithê Rocha; Hu, Nan; Dolgalev, Igor; Roshan, Mona; Foster, James W; Tsirigos, Aristotelis; Wahlin, Karl J; Chakravarti, Shukti
The cornea is a protective and refractive barrier in the eye crucial for vision. Understanding the human cornea in health, disease, and cell-based treatments can be greatly advanced with cornea organoids developed in culture from induced pluripotent stem cells. While a limited number of studies have investigated the single-cell transcriptomic composition of the human cornea, its organoids have not been examined similarly. Here, we elucidated the transcriptomic cell fate map of 4-month-old human cornea organoids and human donor corneas. The organoids harbor cell clusters that resemble cells of the corneal epithelium, stroma, and endothelium, with subpopulations that capture signatures of early developmental states. Unlike the adult cornea where the largest cell population is stromal, the organoids contain large proportions of epithelial and endothelial-like cells. These corneal organoids offer a 3D model to study corneal diseases and integrated responses of different cell types.
PMCID:9802453
PMID: 36712326
ISSN: 2752-6542
CID: 5430182

Genetic Disorders of the Extracellular Matrix: From Cell and Gene Therapy to Future Applications in Regenerative Medicine

Chakravarti, Shukti; Enzo, Elena; de Barros, Maithê Rocha Monteiro; Maffezzoni, Maria Benedetta Rizzarda; Pellegrini, Graziella
Metazoans have evolved to produce various types of extracellular matrix (ECM) that provide structural support, cell adhesion, cell-cell communication, and regulated exposure to external cues. Epithelial cells produce and adhere to a specialized sheet-like ECM, the basement membrane, that is critical for cellular homeostasis and tissue integrity. Mesenchymal cells, such as chondrocytes in cartilaginous tissues and keratocytes in the corneal stroma, produce a pericellular matrix that presents optimal levels of growth factors, cytokines, chemokines, and nutrients to the cell and regulates mechanosensory signals through specific cytoskeletal and cell surface receptor interactions. Here, we discuss laminins, collagen types IV and VII, and perlecan, which are major components of these two types of ECM. We examine genetic defects in these components that cause basement membrane pathologies such as epidermolysis bullosa, Alport syndrome, rare pericellular matrix-related chondrodysplasias, and corneal keratoconus and discuss recent advances in cell and gene therapies being developed for some of these disorders. Expected final online publication date for the Annual Review of Genomics and Human Genetics, Volume 23 is October 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
PMID: 35537467
ISSN: 1545-293x
CID: 5214312

Multimodal Noninvasive Functional Neurophotonic Imaging of Murine Brain-Wide Sensory Responses

Chen, Zhenyue; Zhou, Quanyu; Dean-Ben, Xose Luis; Gezginer, Irmak; Ni, Ruiqing; Reiss, Michael; Shoham, Shy; Razansky, Daniel
Modern optical neuroimaging approaches are expanding the ability to elucidate complex brain function. Diverse imaging contrasts enable direct observation of neural activity with functional sensors along with the induced hemodynamic responses. To date, decoupling the complex interplay of neurovascular coupling and dynamical physiological states has remained challenging when employing single-modality functional neuroimaging readings. A hybrid fluorescence optoacoustic tomography platform combined with a custom data processing pipeline based on statistical parametric mapping is devised, attaining the first noninvasive observation of simultaneous calcium and hemodynamic activation patterns using optical contrasts. Correlated changes in the oxy- and deoxygenated hemoglobin, total hemoglobin, oxygen saturation, and rapid GCaMP6f fluorescence signals are observed in response to peripheral sensory stimulation. While the concurrent epifluorescence serves to corroborate and complement the functional optoacoustic observations, the latter further aids in decoupling the rapid calcium responses from the slowly varying background in the fluorescence recordings mediated by hemodynamic changes. The hybrid imaging platform expands the capabilities of conventional neuroimaging methods to provide more comprehensive functional readings for studying neurovascular and neurometabolic coupling mechanisms and related diseases.
PMID: 35798308
ISSN: 2198-3844
CID: 5284812

Apparent lack of association of COVID-19 vaccination with Herpes Zoster

Patil, Sachi A; Dygert, Levi; Galetta, Steven L; Balcer, Laura J; Cohen, Elisabeth J
Purpose/UNASSIGNED:Herpes zoster (HZ) has been identified as a potential association with the BNT162b2 COVID-19 vaccination. This study evaluated this possible association in a cohort of patients receiving the vaccination. Methods/UNASSIGNED:Epic electronic health records of adult patients who received at least one COVID-19 vaccination between January 12, 2020 and 9/30/2021 within the NYU Langone Health were reviewed to analyze a new diagnosis of herpes zoster within 3 months before compared to 3 months after vaccination. Results/UNASSIGNED:Of the 596,111 patients who received at least one COVID-19 vaccination, 716 patients were diagnosed with HZ within three months prior to vaccination, compared to 781 patients diagnosed within 3 months afterwards. Using the chi-square test for independence of proportions, there was not a statistically significant difference in frequency of HZ before (proportion: 0.0012, 95% CI: [0.0011, 0.0013]) vs. after vaccination (proportion: 0.0013, 95% CI: [0.0012, 0.0014]); (p = 0.093). Conclusions and importance/UNASSIGNED:This study did not find evidence of an association between COVID-19 vaccination and a new diagnosis of HZ. We encourage health care professionals to strongly recommend COVID-19 vaccinations per Centers for Disease Control (CDC) recommendations and vaccination against HZ according to Food and Drug Administration (FDA) approval for the recombinant zoster vaccine.
PMCID:9021123
PMID: 35474754
ISSN: 2451-9936
CID: 5217432

Zoster Eye Disease Study: Rationale and Design

Cohen, Elisabeth J; Hochman, Judith S; Troxel, Andrea B; Colby, Kathryn A; Jeng, Bennie H
PURPOSE/OBJECTIVE:The purpose of this study was to describe the rationale and design of the Zoster Eye Disease Study (ZEDS). METHODS:ZEDS is a National Eye Institute-supported randomized clinical trial designed to determine whether 1 year of suppressive valacyclovir in patients with herpes zoster ophthalmicus (HZO) reduces complications because there is currently no high-quality evidence to support its use. Eligible patients are 18 years and older, immunocompetent, have a history of a typical rash at disease onset, and have had a record of active epithelial or stromal keratitis or iritis within 1 year before enrollment. Exclusion criteria include estimated glomerular filtration rate less than 45 or pregnancy. The primary endpoint is the time to first occurrence of new or worsening dendriform epithelial keratitis, stromal keratitis without or with ulceration, endothelial keratitis, or iritis due to HZO during 12 months of study treatment requiring prespecified treatment changes. The study has 80% power to detect a 30% difference between treatment groups, with a 30% rate of endpoints by 1 year assumed among controls. Secondary and exploratory questions include whether there is a persistent treatment benefit during the 6 months after treatment, whether development of postherpetic neuralgia varies by treatment group, and whether vaccinations against herpes zoster affect study outcomes and coronavirus disease 19 status. RESULTS:Over approximately 4 years, over 400 study participants have been enrolled. CONCLUSIONS:ZEDS aims to provide scientific evidence on whether suppressive valacyclovir treatment improves outcomes in HZO and should become the standard of care.
PMID: 35090154
ISSN: 1536-4798
CID: 5154932

Glymphatic imaging and modulation of the optic nerve

Kasi, Anisha; Liu, Crystal; Faiq, Muneeb A; Chan, Kevin C
Optic nerve health is essential for proper function of the visual system. However, the pathophysiology of certain neurodegenerative disease processes affecting the optic nerve, such as glaucoma, is not fully understood. Recently, it was hypothesized that a lack of proper clearance of neurotoxins contributes to neurodegenerative diseases. The ability to clear metabolic waste is essential for tissue homeostasis in mammals, including humans. While the brain lacks the traditional lymphatic drainage system identified in other anatomical regions, there is growing evidence of a glymphatic system in the central nervous system, which structurally includes the optic nerve. Named to acknowledge the supportive role of astroglial cells, this perivascular fluid drainage system is essential to remove toxic metabolites from the central nervous system. Herein, we review existing literature describing the physiology and dysfunction of the glymphatic system specifically as it relates to the optic nerve. We summarize key imaging studies demonstrating the existence of a glymphatic system in the optic nerves of wild-type rodents, aquaporin 4-null rodents, and humans; glymphatic imaging studies in diseases where the optic nerve is impaired; and current evidence regarding pharmacological and lifestyle interventions that may help promote glymphatic function to improve optic nerve health. We conclude by highlighting future research directions that could be applied to improve imaging detection and guide therapeutic interventions for diseases affecting the optic nerve.
PMCID:8552868
PMID: 34558505
ISSN: 1673-5374
CID: 5110742

Pathogenesis of keratoconus: NRF2-antioxidant, extracellular matrix and cellular dysfunctions

Monteiro de Barros, Maithê Rocha; Chakravarti, Shukti
Keratoconus (KC) is a degenerative disease associated with cell and extracellular matrix (ECM) loss that causes gradual thinning and steepening of the cornea and loss of vision. Collagen cross linking with ultraviolet light treatment can strengthen the ECM and delay weakening of the cornea, but severe cases require corneal transplantation. KC is multifactorial and multigenic, but its pathophysiology is still an enigma. Multiple approaches are being pursued to elucidate the molecular changes that underlie the corneal phenotype to identify relevant genes for tailored candidate searches and to develop potential biomarkers and targets for therapeutic interventions. Recent proteomic and transcriptomic studies suggest dysregulations in oxidative stress, NRF2-regulated antioxidant programs, WNT-signaling, TGF-β, ECM and matrix metalloproteinases. This review aims to provide a broad update on the transcriptomic and proteomic studies of KC with a focus on findings that relate to oxidative stress, and dysregulations in cellular and extracellular matrix functions.
PMID: 35385756
ISSN: 1096-0007
CID: 5201652

Advanced Diffusion MRI of the Visual System in Glaucoma: From Experimental Animal Models to Humans

Mendoza, Monica; Shotbolt, Max; Faiq, Muneeb A; Parra, Carlos; Chan, Kevin C
Glaucoma is a group of ophthalmologic conditions characterized by progressive retinal ganglion cell death, optic nerve degeneration, and irreversible vision loss. While intraocular pressure is the only clinically modifiable risk factor, glaucoma may continue to progress at controlled intraocular pressure, indicating other major factors in contributing to the disease mechanisms. Recent studies demonstrated the feasibility of advanced diffusion magnetic resonance imaging (dMRI) in visualizing the microstructural integrity of the visual system, opening new possibilities for non-invasive characterization of glaucomatous brain changes for guiding earlier and targeted intervention besides intraocular pressure lowering. In this review, we discuss dMRI methods currently used in visual system investigations, focusing on the eye, optic nerve, optic tract, subcortical visual brain nuclei, optic radiations, and visual cortex. We evaluate how conventional diffusion tensor imaging, higher-order diffusion kurtosis imaging, and other extended dMRI techniques can assess the neuronal and glial integrity of the visual system in both humans and experimental animal models of glaucoma, among other optic neuropathies or neurodegenerative diseases. We also compare the pros and cons of these methods against other imaging modalities. A growing body of dMRI research indicates that this modality holds promise in characterizing early glaucomatous changes in the visual system, determining the disease severity, and identifying potential neurotherapeutic targets, offering more options to slow glaucoma progression and to reduce the prevalence of this world's leading cause of irreversible but preventable blindness.
PMCID:8945790
PMID: 35336827
ISSN: 2079-7737
CID: 5220492

In vivo MRI evaluation of anterograde manganese transport along the visual pathway following whole eye transplantation

Komatsu, Chiaki; van der Merwe, Yolandi; He, Lin; Kasi, Anisha; Sims, Jeffrey R; Miller, Maxine R; Rosner, Ian A; Khatter, Neil J; Su, An-Jey A; Schuman, Joel S; Washington, Kia M; Chan, Kevin C
BACKGROUND:administration into both native and transplanted eyes. RESULTS: No significant intraocular pressure difference was found between native and transplanted eyes, whereas comparable manganese enhancement was observed between native and transplanted intraorbital optic nerves, suggesting the presence of anterograde manganese transport after WET. No enhancement was detected across the coaptation site in the higher visual areas of the recipient brain. Comparison with Existing Methods: Existing imaging methods to assess WET focus on either the eye or local optic nerve segments without direct visualization and longitudinal quantification of physiological transport along the transplanted visual pathway, hence the development of in vivo MEMRI. CONCLUSION/CONCLUSIONS: Our established imaging platform indicated that essential physiological transport exists in the transplanted optic nerve after WET. As neuroregenerative approaches are being developed to connect the transplanted eye to the recipient's brain, in vivo MEMRI is well-suited to guide strategies for successful WET integration for vision restoration. Keywords (Max 6): Anterograde transport, magnetic resonance imaging, manganese, neuroregeneration, optic nerve, whole-eye transplantation.
PMID: 35202613
ISSN: 1872-678x
CID: 5167792