Publications

2021

Tomita Y, Qiu C, Bull E, Allen W, Kotoda Y, Talukdar S, Smith L, Fu Z. Müller glial responses compensate for degenerating photoreceptors in retinitis pigmentosa. Exp Mol Med. 2021;
Photoreceptor degeneration caused by genetic defects leads to retinitis pigmentosa, a rare disease typically diagnosed in adolescents and young adults. In most cases, rod loss occurs first, followed by cone loss as well as altered function in cells connected to photoreceptors directly or indirectly. There remains a gap in our understanding of retinal cellular responses to photoreceptor abnormalities. Here, we utilized single-cell transcriptomics to investigate cellular responses in each major retinal cell type in retinitis pigmentosa model (P23H) mice vs. wild-type littermate mice. We found a significant decrease in the expression of genes associated with phototransduction, the inner/outer segment, photoreceptor cell cilium, and photoreceptor development in both rod and cone clusters, in line with the structural changes seen with immunohistochemistry. Accompanying this loss was a significant decrease in the expression of genes involved in metabolic pathways and energy production in both rods and cones. We found that in the Müller glia/astrocyte cluster, there was a significant increase in gene expression in pathways involving photoreceptor maintenance, while concomitant decreases were observed in rods and cones. Additionally, the expression of genes involved in mitochondrial localization and transport was increased in the Müller glia/astrocyte cluster. The Müller glial compensatory increase in the expression of genes downregulated in photoreceptors suggests that Müller glia adapt their transcriptome to support photoreceptors and could be thought of as general therapeutic targets to protect against retinal degeneration.
Greiner J, Glonek T. Intracellular ATP Concentration and Implication for Cellular Evolution. Biology (Basel). 2021;10(11).
Crystalline lens and striated muscle exist at opposite ends of the metabolic spectrum. Lens is a metabolically quiescent tissue, whereas striated muscle is a mechanically dynamic tissue with high-energy requirements, yet both tissues contain millimolar levels of ATP (>2.3 mM), far exceeding their underlying metabolic needs. We explored intracellular concentrations of ATP across multiple cells, tissues, species, and domains to provide context for interpreting lens/striated muscle data. Our database revealed that high intracellular ATP concentrations are ubiquitous across diverse life forms including species existing from the Precambrian Era, suggesting an ancient highly conserved role for ATP, independent of its widely accepted view as primarily "metabolic currency". Our findings reinforce suggestions that the primordial function of ATP was non-metabolic in nature, serving instead to prevent protein aggregation.
Kolomeyer N, Katz L, Hark L, Wahl M, Gajwani P, Aziz K, Myers J, Friedman D. Lessons Learned From 2 Large Community-based Glaucoma Screening Studies. J Glaucoma. 2021;30(10):875–877.
Community-based screening programs have had limited success in preventing vision loss from glaucoma due to overall low prevalence of glaucoma, screening limitations, and barriers to follow-up appointments. This editorial highlights lessons learned from 2 large prospective trials: the Philadelphia Telemedicine Glaucoma Detection and Follow-up Study and the Screening To Prevent Glaucoma Study. While some lessons are specific to ophthalmology, many lessons are applicable to screening for asymptomatic diseases in underserved, vulnerable communities.
Maguire M, Liu D, Bressler S, Friedman S, Melia M, Stockdale C, Glassman A, Sun J, DRCR Retina Network. Lapses in Care Among Patients Assigned to Ranibizumab for Proliferative Diabetic Retinopathy: A Post Hoc Analysis of a Randomized Clinical Trial. JAMA Ophthalmol. 2021;139(12):1266–1273.
Importance: The follow-up schedule for individuals with eyes treated with anti-vascular endothelial growth factor agents for proliferative diabetic retinopathy (PDR) requires that patients return frequently for monitoring and repeated treatment. The likelihood that a patient will comply should be a consideration in choosing a treatment approach. Objective: To describe completion of scheduled examinations among participants assigned to intravitreous injections of ranibizumab for PDR in a multicenter randomized clinical trial. Design, Setting, and Participants: This post hoc analysis evaluates data from a randomized clinical trial conducted at 55 US sites among 305 adults with proliferative diabetic retinopathy enrolled between February and December 2012. Both eyes were enrolled for 89 participants (1 eye to each study group), with a total of 394 study eyes. The final 2-year visit was completed in January 2015. Data were analyzed from April 2019 to July 2021. Interventions: Ranibizumab injections for PDR or macular edema. Main Outcomes and Measures: A long lapse in care of 8 or more weeks past a scheduled examination, dropout from follow-up, visual acuity at 5 years. Results: Among 170 participants, the median age was 51 years, and 44.7% were female. Through 5 years of follow-up, 94 of 170 participants (55.3%) had 1 or more long lapse in care. Median time to the first long lapse was 210 weeks, and 69 of 94 participants (73.4%) returned for examination after the first long lapse. Fifty of 170 participants (29.4%) dropped out of follow-up by 5 years. Among the 120 participants who completed the 5-year examination, median change from baseline in visual acuity was -2 letters for participants who had 1 or more long lapse compared with +5 letters for those without a long lapse (P = .02). After multivariable adjustment, the odds ratio (95% CI) for baseline associations with 1 or more long lapse was 1.21 (1.03-1.43) for each 5-letter decrement in visual acuity score, 2.19 (1.09-4.38) for neovascularization of the disc and elsewhere, and 3.48 (1.38-8.78) for no prior laser treatment for diabetic macular edema. Conclusions and Relevance: Over 5 years, approximately half of the participants assigned to ranibizumab for PDR had a long lapse in care despite substantial effort by the DRCR Retina Network to facilitate timely completion of examinations. The likelihood of a long lapse in care during long-term follow-up needs to be considered when choosing treatment for PDR. Trial Registration: ClinicalTrials.gov Identifier: NCT01489189.
Hellström A, Pivodic A, Gränse L, Lundgren P, Sjöbom U, Nilsson A, Söderling H, Hård AL, Smith L, Löfqvist CA. Association of Docosahexaenoic Acid and Arachidonic Acid Serum Levels With Retinopathy of Prematurity in Preterm Infants. JAMA Netw Open. 2021;4(10):e2128771.
Importance: Supplementing preterm infants with long-chain polyunsaturated fatty acids (LC-PUFA) has been inconsistent in reducing the severity and incidence of retinopathy of prematurity (ROP). Furthermore, few studies have measured the long-term serum lipid levels after supplementation. Objective: To assess whether ROP severity is associated with serum levels of LC-PUFA, especially docosahexaenoic acid (DHA) and arachidonic acid (AA), during the first 28 postnatal days. Design, Setting, and Participants: This cohort study analyzed the Mega Donna Mega study, a randomized clinical trial that provided enteral fatty acid supplementation at 3 neonatal intensive care units in Sweden. Infants included in this cohort study were born at a gestational age of less than 28 weeks between December 20, 2016, and August 6, 2019. Main Outcomes and Measures: Severity of ROP was classified as no ROP, mild or moderate ROP (stage 1-2), or severe ROP (stage 3 and type 1). Serum phospholipid fatty acids were measured through gas chromatography-mass spectrometry. Ordinal logistic regression, with a description of unadjusted odds ratio (OR) as well as gestational age- and birth weight-adjusted ORs and 95% CIs, was used. Areas under the curve were used to calculate mean daily levels of fatty acids during postnatal days 1 to 28. Blood samples were obtained at the postnatal ages of 1, 3, 7, 14, and 28 days. Results: A total of 175 infants were included in analysis. Of these infants, 99 were boys (56.6%); the median (IQR) gestational age was 25 weeks 5 days (24 weeks 3 days to 26 weeks 6 days), and the median (IQR) birth weight was 785 (650-945) grams. A higher DHA proportion was seen in infants with no ROP compared with those with mild or moderate ROP or severe ROP (OR per 0.5-molar percentage increase, 0.49 [95% CI, 0.36-0.68]; gestational age- and birth weight-adjusted OR, 0.66 [95% CI, 0.46-0.93]). The corresponding adjusted OR for AA levels per 1-molar percentage increase was 0.83 (95% CI, 0.66-1.05). The association between DHA levels and ROP severity appeared only in infants with sufficient AA levels, suggesting that a mean daily minimum level of 7.8 to 8.3 molar percentage of AA was necessary for a detectable association between DHA level and less severe ROP. Conclusions and Relevance: This cohort study found that higher mean daily serum levels of DHA during the first 28 postnatal days were associated with less severe ROP even after adjustment for known risk factors, but only in infants with sufficiently high AA levels. Further studies are needed to identify LC-PUFA supplementation strategies that may prevent ROP and other morbidities.
E JY, Mihailovic A, Schrack J, Garzon C, Li T, Friedman D, West S, Gitlin L, Ramulu P. Longitudinal changes in daily patterns of objectively measured physical activity after falls in older adults with varying degrees of glaucoma. EClinicalMedicine. 2021;40:101097.
Background: Visually impaired older adults have a greater risk of falling, making them particularly susceptible to fall-related health consequences and restricted physical activity. Unclear however, is the relationship between having falls and longitudinal changes in daily patterns of objectively measured physical activity in older adults with visual impairments. Methods: We created a three-year prospective cohort study (Falls in Glaucoma Study) of older adults with primary or suspected glaucoma at the Johns Hopkins Wilmer Eye Institute from 2013 to 2015. Cumulative incidence of falls was determined through self-reported fall calendars over 12 months. Participants were then classified into one of three groups: multiple fallers (≥2 falls), single fallers (1 fall), and non-fallers (0). Daily physical activity was measured over 1 week using a waist-bound accelerometer during baseline and three-year follow-ups. Activity fragmentation was defined as the reciprocal of the mean activity bout length, with higher fragmentation reflecting shorter, more fractured bouts of continuous activity. Multivariate linear mixed-effects models were used to assess three-year longitudinal changes in: 1) activity fragmentation, and 2) accumulation of activity across six three-hour intervals from 5 AM to 11 PM. Findings: In adjusted models accounting for visual field damage and other factors, multiple fallers demonstrated greater annual declines (per year) in daily active bouts (-1.79 bouts/day, 95% confidence interval [CI]: -3.35, -0.22), daily active minutes (-17.15 min/day, 95% CI: -26.35, -7.94), and increased fragmentation (1%, 95% CI: 0, 2%) over the three-year follow-up period as compared to non-fallers; no such changes were seen when comparing single fallers and non-fallers. In time-of-day analyses, multiple fallers experienced greater annual declines in average hourly steps over all periods of the day, though the rate of decline was only significant between 5 PM and 8 PM (-27.07 steps/hour, 95% CI: -51.15, -2.99) compared to non-fallers. Interpretation: In an older population with visual impairment, multiple falls over 12 months were associated with more transient and fragmented activity over a subsequent three-year period, and activity declines during evening hours, compared to non-fallers. These findings suggest that multiple fallers with visual impairment may be at high risk for a decline in physical capacity and endurance, warranting clinical interventions. Funding: The research was supported in part by National Institutes of Health Grant EY022976.
Whitman M, Barry B, Robson C, Facio F, Van Ryzin C, Chan WM, Lehky T, Thurm A, Zalewski C, King K, Brewer C, Almpani K, Lee J, Delaney A, FitzGibbon E, Lee P, Toro C, Paul S, Abdul-Rahman O, Webb B, Jabs EW, Moller HU, Larsen DA, Antony J, Troedson C, Ma A, Ragnhild G, Wirgenes K, Tham E, Kvarnung M, Maarup TJ, MacKinnon S, Hunter D, Collins F, Manoli I, Engle E. TUBB3 Arg262His causes a recognizable syndrome including CFEOM3, facial palsy, joint contractures, and early-onset peripheral neuropathy. Hum Genet. 2021;140(12):1709–1731.
Microtubules are formed from heterodimers of alpha- and beta-tubulin, each of which has multiple isoforms encoded by separate genes. Pathogenic missense variants in multiple different tubulin isoforms cause brain malformations. Missense mutations in TUBB3, which encodes the neuron-specific beta-tubulin isotype, can cause congenital fibrosis of the extraocular muscles type 3 (CFEOM3) and/or malformations of cortical development, with distinct genotype-phenotype correlations. Here, we report fourteen individuals from thirteen unrelated families, each of whom harbors the identical NM_006086.4 (TUBB3):c.785G>A (p.Arg262His) variant resulting in a phenotype we refer to as the TUBB3 R262H syndrome. The affected individuals present at birth with ptosis, ophthalmoplegia, exotropia, facial weakness, facial dysmorphisms, and, in most cases, distal congenital joint contractures, and subsequently develop intellectual disabilities, gait disorders with proximal joint contractures, Kallmann syndrome (hypogonadotropic hypogonadism and anosmia), and a progressive peripheral neuropathy during the first decade of life. Subsets may also have vocal cord paralysis, auditory dysfunction, cyclic vomiting, and/or tachycardia at rest. All fourteen subjects share a recognizable set of brain malformations, including hypoplasia of the corpus callosum and anterior commissure, basal ganglia malformations, absent olfactory bulbs and sulci, and subtle cerebellar malformations. While similar, individuals with the TUBB3 R262H syndrome can be distinguished from individuals with the TUBB3 E410K syndrome by the presence of congenital and acquired joint contractures, an earlier onset peripheral neuropathy, impaired gait, and basal ganglia malformations.
Jung JH, Kurukuti NM, Peli E. Photographic Depiction of the Field of View with Spectacles-mounted Low Vision Aids. Optom Vis Sci. 2021;98(10):1210–1226.
SIGNIFICANCE: Photographic depiction helps to illustrate the primary and secondary field of view effects of low vision devices along with their utility to clinicians, patients, and caretakers. This technique may also be helpful for designers and researchers in improving the design and fitting of low vision devices. PURPOSE: The field of view through spectacles-mounted low vision devices has typically been evaluated using perimetry. However, the perimetric field diagram is different from the retinal image and often fails to represent the important aspects of the field of view and visual parameters. We developed a photographic depiction method to record and veridically show the field of view effects of these devices. METHODS: We used a 3D-printed holder to place spectacles-mounted devices at the same distance from the empirically determined reference point of the field of view in a camera lens (f = 16 mm) as they would be from an eye, when in use. The field of view effects of a bioptic telescope, a minifier (reverse telescope), and peripheral prisms were captured using a conventional camera, representing retinal images. The human eye pupil size (adjusting the F number: f/2.8 to f/8 and f/22 in the camera lens) and fitting parameters (pantoscopic tilt and back vertex distance) varied. RESULTS: Real-world indoor and outdoor walking and driving scenarios were depicted as retinal images illustrating the field of view through low vision devices, distinguishing optical and obscuration scotomas, and demonstrating secondary effects (spatial distortions, viewpoint changes, diplopia, spurious reflection, and multiplexing effects) not illustrated by perimetric field diagrams. CONCLUSIONS: Photographic depiction illustrates the primary and secondary field of view effects of the low vision devices. These images highlight the benefit and possible trade-offs of the low vision devices and may be beneficial in education and training.