Publications

2021

Greenwald S, Brown E, Scandura M, Hennessey E, Farmer R, Du J, Wang Y, Pierce E. Mutant Nmnat1 leads to a retina-specific decrease of NAD+ accompanied by increased poly(ADP-ribose) in a mouse model of NMNAT1-associated retinal degeneration. Hum Mol Genet. 2021;30(8):644–657.
Nicotinamide mononucleotide adenylyltransferase 1 (NMNAT1) is required for nuclear nicotinamide adenine mononucleotide (NAD+) biosynthesis in all nucleated cells, and despite its functional ubiquity, mutations in this gene lead to an isolated retinal degeneration. The mechanisms underlying how mutant NMNAT1 causes disease are not well understood, nor is the reason why the pathology is confined to the retina. Using a mouse model of NMNAT1-associated retinal degeneration that harbors the p.Val9Met mutation, we tested the hypothesis that decreased function of mutant NMNAT1 has a greater effect on the levels of NAD+ in the retina than elsewhere in the body. Measurements by liquid chromatography with tandem mass spectrometry showed an early and sustained decrease of NAD+ in mutant retinas that was not observed in other tissues. To understand how consumers of nuclear NAD+ are affected by the reduced availability of NAD+ in mutant retinas, poly(ADP-ribose) polymerase (PARP) and nuclear sirtuin activity were evaluated. PARP activity was elevated during disease progression, as evidenced by overproduction of poly(ADP-ribose) (PAR) in photoreceptors, whereas histone deacetylation activity of nuclear sirtuins was not altered. We hypothesized that PARP could be activated because of elevated levels of oxidative stress; however, we did not observe oxidative DNA damage, lipid peroxidation, or a low glutathione to oxidized glutathione ratio. Terminal deoxynucleotidyl transferase dUTP nick end labeling staining revealed that photoreceptors appear to ultimately die by apoptosis, although the low NAD+ levels and overproduction of PAR suggest that cell death may include aspects of the parthanatos cell death pathway.
Brill D, Papaliodis G. Uveitis Specialists Harnessing Disruptive Technology during the COVID-19 Pandemic and Beyond. Semin Ophthalmol. 2021;36(4):296–303.
Spurred by the coronavirus disease pandemic and shortage of eye care providers, telemedicine is transforming the way ophthalmologists care for their patients. Video conferencing, ophthalmic imaging, hybrid visits, intraocular inflammation quantification, and portable technology are evolving areas that may allow more uveitis patients to be evaluated via telemedicine. Despite these promising disruptive technologies, there remain significant technological limitations, legal barriers, variable insurance coverage for virtual visits, and lack of clinical trials for uveitis specialists to embrace telemedicine.
Shanbhag S, Shih G, Bispo P, Chodosh J, Jacobs D, Saeed H. Diphtheroids as Corneal Pathogens in Chronic Ocular Surface Disease in Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis. Cornea. 2021;40(6):774–779.
PURPOSE: To characterize diphtheroid corneal infections in eyes in the chronic phase of Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN). METHODS: Observational case series. RESULTS: Four eyes of 3 patients were included in this review. Each eye presented with persistent corneal epithelial defect with corneal thinning in the chronic phase of SJS/TEN. None of the epithelial defects were associated with stromal infiltration. The corneas were cultured at the time of workup of persistent epithelial defect (3 eyes) or at time of tectonic penetrating keratoplasty after perforation (1 eye). Cultures yielded abundant growth of Corynebacterium spp., including Corynebacterium jeikeium (n = 2), Corynebacterium glucuronolyticum (n = 1), and a multidrug-resistant Corynebacterium striatum isolate (n = 1). The ocular surface was stabilized with surgical intervention (1 eye) or with introduction of fortified topical antibiotic based on laboratory identification and susceptibility testing of the isolated organisms (3 eyes). Numerous risk factors for microbial keratitis were present in all 4 eyes. CONCLUSIONS: In eyes with a persistent corneal epithelial defect in the chronic phase of SJS/TEN, even in the absence of an infiltrate, corneal culture should be undertaken. Recognition and treatment of Corynebacterium spp. as opportunistic pathogens may lead to favorable outcomes in cases of clinically sterile ulceration during the chronic phase of SJS/TEN.
Moustafa G, Borkar D, Eton E, Koulisis N, Kloek C, PCIOL Study Group Members, PCIOL Study Group Members. Healthcare disparities contribute to missed follow-up visits after cataract surgery in the USA: results from the perioperative care for intraocular lens study. BMJ Open. 2021;11(3):e038565.
OBJECTIVE: To identify factors that contribute to missed cataract surgery follow-up visits, with an emphasis on socioeconomic and demographic factors. METHODS: In this retrospective cohort study, patients who underwent cataract extraction by phacoemulsification at Massachusetts Eye and Ear between 1 January and 31 December 2014 were reviewed. Second eye cases, remote and international patients, patients with foreign insurance and combined cataract cases were excluded. RESULTS: A total of 1931 cases were reviewed and 1089 cases, corresponding to 3267 scheduled postoperative visits, were included. Of these visits, 157 (4.8%) were missed. Three (0.3%) postoperative day 1, 40 (3.7%) postoperative week 1 and 114 (10.5%) postoperative month 1 visits were missed. Age<30 years (adjusted OR (aOR)=8.2, 95% CI 1.9 to 35.2) and ≥90 years (aOR=5.7, 95% CI 2.0 to 15.6) compared with patients aged 70-79 years, estimated travel time of >2 hours (aOR=3.2, 95% CI 1.4 to 7.4), smokers (aOR=2.7, 95% CI 1.6 to 4.8) and complications identified up to the postoperative visit (aOR=1.4, 95% CI 1.0 to 2.1) predicted a higher rate of missed visits. Ocular comorbidities (aOR=0.7, 95% CI 0.5 to 1.0) and previous visit best-corrected visual acuity (BCVA) of 20/50-20/80 (aOR=0.4, 95% CI 0.3 to 0.7) and 20/90-20/200 (aOR=0.4, 95% CI 0.2 to 0.9), compared with BCVA at the previous visit of 20/40 or better, predicted a lower rate of missed visits. Gender, race/ethnicity, language, education, income, insurance, alcohol use and season of the year were not associated with missed visits. CONCLUSIONS: Medical factors and demographic characteristics, including patient age and distance from the hospital, are associated with missed follow-up visits in cataract surgery. Additional studies are needed to identify disparities in cataract postoperative care that are population-specific. This information can contribute to the implementation of policies and interventions for addressing them.
Nguyen QD, Anesi S, Chexal S, Chu D, Dayani P, Leng T, Meleth A, Sallam A, Sheppard J, Silverstein S, Toyos M, Wang R, Foster CS. Management of repository corticotropin injection therapy for non-infectious uveitis: a Delphi study. Acta Ophthalmol. 2021;99(6):669–678.
PURPOSE: Diagnosis and management of non-infectious uveitis (NIU), a major cause of blindness worldwide, are challenging. Corticosteroids, the cornerstone of therapy, are not appropriate for long-term use, and while non-biologic and biologic immunomodulators may be used for some patients, data on their efficacy and safety in this population are limited. Repository corticotropin injection (RCI), believed to affect uveitis by multiple mechanisms, has received regulatory approval for treatment of ophthalmic diseases including posterior uveitis, but is not widely used or discussed in guidelines for the management of uveitis and ocular inflammatory diseases. METHODS: The index study employed a modified Delphi process with a panel of 14 US-based ophthalmologists. Consensus recommendations were developed through a series of three questionnaires. Panellists rated statements on a Likert scale from -5 (strongly disagree) to +5 (strongly agree). RESULTS: The Delphi panel provided consensus recommendations on examinations and testing needed for diagnosis, treatment goals, and the use of corticosteroids, as well as the use of non-biologic and biologic immunomodulators. The panel reached consensus that RCI may be considered for posterior and pan-uveitis, and dosing should be individualized for each patient. Dose reduction/discontinuation should be considered for excessive RCI-related toxicity, hyperglycaemia and/or diabetic complications, excessive costs, or remission ≥ 2 years. Patients should be weaned from RCI if uveitis is stable and well controlled. Adverse events during RCI therapy can be managed by appropriate interventions, with dose reduction/discontinuation considered if events are severe or recurrent. CONCLUSIONS: Expert consensus suggests RCI may be an appropriate treatment option for some patients with uveitis when other therapies are ineffective or intolerable.
In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.
Zhang YJ, Jimenez L, Azova S, Kremen J, Chan YM, Elhusseiny A, Saeed H, Goldsmith J, Al-Ibraheemi A, O’Connell A, Kovbasnjuk O, Rodan L, Agrawal P, Thiagarajah J. Novel variants in the stem cell niche factor WNT2B define the disease phenotype as a congenital enteropathy with ocular dysgenesis. Eur J Hum Genet. 2021;29(6):998–1007.
WNT2B is a member of the Wnt family, a group of signal transduction proteins involved in embryologic development and stem cell renewal and maintenance. We recently reported homozygous nonsense variants in WNT2B in three individuals with severe, neonatal-onset diarrhea, and intestinal failure. Here we present a fourth case, from a separate family, with neonatal diarrhea associated with novel compound heterozygous WNT2B variants. One of the two variants was a frameshift variant (c.423del [p.Phe141fs]), while the other was a missense change (c.722 G > A [p.G241D]) that we predict through homology modeling to be deleterious, disrupting post-translational acylation. This patient presented as a neonate with severe diet-induced (osmotic) diarrhea and growth failure resulting in dependence on parenteral nutrition. Her gastrointestinal histology revealed abnormal cellular architecture particularly in the stomach and colon, including oxyntic atrophy, abnormal distribution of enteroendocrine cells, and a paucity of colonic crypt glands. In addition to her gastrointestinal findings, she had bilateral corneal clouding and atypical genital development later identified as a testicular 46,XX difference/disorder of sexual development. Upon review of the previously reported cases, two others also had anterior segment ocular anomalies though none had atypical genital development. This growing case series suggests that variants in WNT2B are associated with an oculo-intestinal (and possibly gonadal) syndrome, due to the protein's putative involvement in multiple developmental and stem cell maintenance pathways.