Publications

2018

Jorge A, Ung C, Young L, Melles R, Choi H. Hydroxychloroquine retinopathy - implications of research advances for rheumatology care. Nat Rev Rheumatol. 2018;14(12):693–703.
Despite advances in therapy for rheumatic diseases, hydroxychloroquine remains almost universally recommended for the treatment of systemic lupus erythematosus (SLE), and is often used in the management of other rheumatic diseases such as rheumatoid arthritis (RA). However, the major dose-limiting toxicity of hydroxychloroquine is retinopathy that can lead to loss of vision. New highly sensitive screening methods can identify early stages of retinopathy, and studies that include these modalities have indicated a substantially higher prevalence of hydroxychloroquine retinopathy than was previously recognized, resulting in revisions to ophthalmology guidelines and the recommendation of a low dose of hydroxychloroquine for many patients. However, the efficacy of low-dose hydroxychloroquine for treating SLE and other rheumatic diseases is unknown. Further studies are required to establish the effectiveness and retinal safety of the latest hydroxychloroquine treatment recommendations.
Liu Y, Chen D, Chen X, Kam W, Hatton M, Sullivan D. Hypoxia: A breath of fresh air for the meibomian gland. Ocul Surf. 2018;
PURPOSE: Optimal meibomian gland (MG) function is critically important for the health and wellbeing of the ocular surface. We hypothesize that low oxygen (O) conditions promote the function of human MG epithelial cells (HMGECs) and that human MGs exist in a relatively hypoxic environment. The purpose of this study was to test our hypotheses. METHODS: We used human and mouse eyelid segments, and immortalized human MG epithelial cells (IHMGECs) in our studies. To evaluate oxygen (O) levels in the mouse MG and vicinity, we injected pimonidazole (pimo), a hypoxia marker, before sacrifice. Human eyelid samples were stained with the hypoxia marker glucose transporter 1 (Glut-1). To determine the effect of low O levels on IHMGECs, we cultured cells under proliferating and differentiating conditions in both normoxic (21% O) and hypoxic (3% O) conditions for 5-15 days. IHMGECs were evaluated for cell number, neutral lipid content, lysosome accumulation, expression of biomarker proteins and DNase II activity. RESULTS: Our results demonstrate that human and mouse MGs, but not the surrounding connective tissue, exist in a relatively hypoxic environment in vivo. In addition, our findings show that hypoxia does not influence IHMGEC numbers in basal or proliferating culture conditions, but does stimulate the expression of SREBP-1 in differentiating IHMGECs. Hypoxia also significantly increased DNase II activity, and apparently IHMGEC terminal differentiation. CONCLUSIONS: Our Results support our hypotheses, and indicate that relative hypoxia promotes MG function.
Manoli I, Sysol J, Epping M, Li L, Wang C, Sloan J, Pass A, Gagné J, Ktena Y, Li L, Trivedi N, Ouattara B, Zerfas P, Hoffmann V, Abu-Asab M, Tsokos M, Kleiner D, Garone C, Cusmano-Ozog K, Enns G, Vernon H, Andersson H, Grunewald S, Elkahloun A, Girard C, Schnermann J, DiMauro S, Andres-Mateos E, Vandenberghe L, Chandler R, Venditti C. FGF21 underlies a hormetic response to metabolic stress in methylmalonic acidemia. JCI Insight. 2018;3(23).
Methylmalonic acidemia (MMA), an organic acidemia characterized by metabolic instability and multiorgan complications, is most frequently caused by mutations in methylmalonyl-CoA mutase (MUT). To define the metabolic adaptations in MMA in acute and chronic settings, we studied a mouse model generated by transgenic expression of Mut in the muscle. Mut-/-;TgINS-MCK-Mut mice accurately replicate the hepatorenal mitochondriopathy and growth failure seen in severely affected patients and were used to characterize the response to fasting. The hepatic transcriptome in MMA mice was characterized by the chronic activation of stress-related pathways and an aberrant fasting response when compared with controls. A key metabolic regulator, Fgf21, emerged as a significantly dysregulated transcript in mice and was subsequently studied in a large patient cohort. The concentration of plasma FGF21 in MMA patients correlated with disease subtype, growth indices, and markers of mitochondrial dysfunction but was not affected by renal disease. Restoration of liver Mut activity, by transgenesis and liver-directed gene therapy in mice or liver transplantation in patients, drastically reduced plasma FGF21 and was associated with improved outcomes. Our studies identify mitocellular hormesis as a hepatic adaptation to metabolic stress in MMA and define FGF21 as a highly predictive disease biomarker.
Smith L, Hellström A, Stahl A, Fielder A, Chambers W, Moseley J, Toth C, Wallace D, Darlow B, Aranda J, Hallberg B, Davis J, Consortium RPWIN. Development of a Retinopathy of Prematurity Activity Scale and Clinical Outcome Measures for Use in Clinical Trials. JAMA Ophthalmol. 2018;
Importance: To facilitate drug and device development for neonates, the International Neonatal Consortium brings together key stakeholders, including pharmaceutical companies, practitioners, regulators, funding agencies, scientists, and families, to address the need for objective, standardized clinical trial outcome measurements to fulfill regulatory requirements. Retinopathy of prematurity (ROP) is a disease that affects preterm neonates. The current International Classification of Retinopathy of Prematurity does not take into account all of the characteristics of ROP and does not adequately discriminate small changes in disease after treatment. These factors are critical for evaluating outcomes in clinical trials. Observations: There is need for an updated ROP acute disease activity and structure scale as well as end-stage structure and ophthalmologic outcome measures designed for use at different ages. The scale and measures, based on current diagnostic methods and treatments, could be used as a guideline for clinical intervention trials. The scale is intended to be validated against retrospective data and revised for use in future trials. An iterative revision process can be accomplished if new measures are added to clinical trials and evaluated at the end of each trial for prognostic value. The new measures would then be incorporated into a new version of the activity scale and the outcome measures revised. Conclusions and Relevance: An ROP activity scale and outcome measures to obtain the most robust and discriminatory data for clinical trials are needed. The scales should be dynamic and modified as knowledge and imaging modalities improve and then validated using data from well-documented clinical trials. This approach is relevant to improving clinical trial data quality.
Wang Z, Liu CH, Huang S, Chen J. Wnt Signaling in vascular eye diseases. Prog Retin Eye Res. 2018;
The Wnt signaling pathway plays a pivotal role in vascular morphogenesis in various organs including the eye. Wnt ligands and receptors are key regulators of ocular angiogenesis both during the eye development and in vascular eye diseases. Wnt signaling participates in regulating multiple vascular beds in the eye including regression of the hyaloid vessels, and development of structured layers of vasculature in the retina. Loss-of-function mutations in Wnt signaling components cause rare genetic eye diseases in humans such as Norrie disease, and familial exudative vitreoretinopathy (FEVR) with defective ocular vasculature. On the other hand, experimental studies in more prevalent vascular eye diseases, such as wet age-related macular degeneration (AMD), diabetic retinopathy (DR), retinopathy of prematurity (ROP), and corneal neovascularization, suggest that aberrantly increased Wnt signaling is one of the causations for pathological ocular neovascularization, indicating the potential of modulating Wnt signaling to ameliorate pathological angiogenesis in eye diseases. This review recapitulates the key roles of the Wnt signaling pathway during ocular vascular development and in vascular eye diseases, and pharmaceutical approaches targeting the Wnt signaling as potential treatment options.
Staphylococcus aureus is an important human pathogen that causes serious antibiotic-resistant infections. Its population structure is marked by the appearance and dissemination of successful lineages across different settings. To begin understanding the population structure of S. aureus causing ocular and otolaryngology infections, we characterized 262 isolates by antimicrobial sensitivity testing and multilocus sequence typing (MLST). Methicillin-resistant S. aureus were subjected to SCCmec typing and Panton-Valentine leukocidin (PVL) screening. Although we detected a high level of genetic diversity among methicillin-sensitive (MSSA) isolates, (63 sequence types-STs), the population was dominated by five lineages: ST30, ST5, ST8, ST15 and ST97. Resistance to penicillin, erythromycin and clindamycin was common among the major MSSA lineages, with fluctuations markedly impacted by genetic background. Isolates belonging to the predominant lineage, ST30, displayed high rates of resistance to penicillin (100%), erythromycin (71%), and clindamycin (63%). Overall, 21% of the isolates were methicillin-resistant (MRSA), with an apparent enrichment among otitis and orbital cellulitis isolates (>40%). MRSA isolates belonged to 14 STs grouped in 5 clonal complexes (CC), however, CC5 (56.1%) and CC8 (38.6%) dominated the population. Most CC5 strains were SCCmec type II, and resembled the hospital-adapted USA100 clone. CC8 strains were SCCmec type IV, and 86% were positive for the PVL toxin, common features of the community-acquired clone USA300. CC5 strains harboring a SCCmec type IV, typical for the USA800 clone, comprised 15.5% of the population. USA100 strains were highly resistant to clindamycin, erythromycin and levofloxacin (100%), while USA300 strains were frequently resistant to erythromycin (89%) but displayed lower rates of resistance to levofloxacin (39%) and clindamycin (17%). Our data demonstrate that the ocular and otolaryngology S. aureus populations are composed of strains that are commonly resistant to clinically relevant antibiotics, and are associated with the major epidemic clonal complexes of both community and hospital origins.
Zhai H, Bispo P, Kobashi H, Jacobs D, Gilmore M, Ciolino J. Resolution of fluoroquinolone-resistant keratitis with a PROSE device for enhanced targeted antibiotic delivery. Am J Ophthalmol Case Rep. 2018;12:73–75.
Purpose: To report the resolution of a fluoroquinolone-resistant keratitis with use of a prosthetic replacement of the ocular surface ecosystem (PROSE) device for enhanced targeted delivery of moxifloxiacin. Observations: A 62-year-old female presented with a 3-day history of pain, photophobia, and declining vision in left eye. The patient had a 2-year history of binocular PROSE treatment for ocular chronic graft-vs-host disease (cGVHD). A corneal ulcer was diagnosed and treated with topical 0.5% moxifloxacin solution 6 times per day, with continued wear of the PROSE device. After 4 days, worsening symptoms led to an increase in application of moxifloxicin to every 2 hours while awake. The drug was administered by removal of the device, cleaning and replenishing the reservoir with sterile saline, and adding one drop of the drug to the reservoir prior to reinsertion. Four days later, the corneal surface was epithelialized with only small subepithelial infiltrate remaining. The corneal culture grew an isolate carrying multiple mutations in the topoisomerase genes. These mutations were correlated with varying levels of resistance to ciprofloxacin (256 μg/mL), levofloxacin (8 μg/mL), and moxifloxacin (16 μg/mL). Conclusions and Importance: Although the infecting strain exhibited resistance to fluoroquinolones, the infection resolved when moxifloxacin was combined with PROSE therapy. Frequent dosing to the PROSE reservoir is likely to increase fluoroquinolone bioavailability and may represent a valuable approach to overcome antibiotic resistance.
Misra P, Marconi A, Peterson M, Kreiman G. Minimal memory for details in real life events. Sci Rep. 2018;8(1):16701.
The extent to which the details of past experiences are retained or forgotten remains controversial. Some studies suggest massive storage while others describe memories as fallible summary recreations of original events. The discrepancy can be ascribed to the content of memories and how memories are evaluated. Many studies have focused on recalling lists of words/pictures, which lack the critical ingredients of real world memories. Here we quantified the ability to remember details about one hour of real life. We recorded video and eye movements while subjects walked along specified routes and evaluated whether they could distinguish video clips from their own experience from foils. Subjects were minimally above chance in remembering the minutiae of their experiences. Recognition of specific events could be partly explained by a machine-learning model of video contents. These results quantify recognition memory for events in real life and show that the details of everyday experience are largely not retained in memory.