301 results on '"Demetrios G Vavvas"'
Search Results
2. Feasibility demonstration of a device for vitreous liquid biopsy incidental to intravitreal injection.
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Alexandre R Tumlinson, Jennifer M Calara, Dimitri T Azar, Anthony P Adamis, Demetrios G Vavvas, and Jay M Stewart
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Medicine ,Science - Abstract
PurposeVitreoDx is an experimental device enabling push-button collection of a neat vitreous liquid biopsy incidental to an intravitreal injection. We explored the ability of the device to collect a sample usable for proteomic biomarker discovery and testing.DesignPilot study using ex vivo human eyes.MethodsNon-vitrectomized, human eyes from nine donors 75-91 years of age were refrigerated in BSS and used within 5 days of death. Four VitreoDx devices fitted with 25G needles, and four staked needle insulin syringes with 30G needles, were inserted at equal intervals through the pars plana of each eye and held in place by a fixture. The sampling mode of each VitreoDx device was triggered to attempt to acquire a liquid biopsy up to 70 μL. The plunger of each insulin syringe was retracted to attempt to obtain a liquid biopsy with a maximum volume of 50 μL. Samples acquired with the VitreoDx were extracted to polypropylene cryovials, refrigerated to -80 ºC, and sent for offsite proteomic analysis by proximity extension assay with a focus on panels containing approved and pipelined drug targets for neovascular disease and inflammatory factors.ResultsOf the attempted liquid biopsies with the novel 25G VitreoDx, 92% (66 of 72) resulted in successful acquisition (>25 μL) while 89% (64 of 72) attempted by a traditional 30G needle resulted in a successful acquisition. Sample volume sufficient for proteomics array analysis was acquired by the VitreoDx for every eye. Detectable protein was found for 151 of 166 unique proteins assayed in at least 25% of eyes sampled by VitreoDx.ConclusionsThe high acquisition rate achieved by the prototype was similar to that achieved in previous clinical studies where a standard syringe was used with a 25G needle to biopsy vitreous fluid directly prior to standard intravitreal injection. Successful aspiration rates were likewise high for 30G needles. Together, these suggest that it is possible to routinely acquire liquid vitreous biopsies from patients who typically receive intravitreal injections with an injection device using a standard size needle without a vitreous cutter. Protein analysis shows that proteins of interest survive the sampling mechanism and may have potential to direct care in the future.
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- 2024
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3. Paediatric ocular adnexal lymphoma: a population-based analysis
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Demetrios G Vavvas, Giannis A Moustafa, Allan K Topham, and Mary E Aronow
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Ophthalmology ,RE1-994 - Abstract
Objective To investigate the incidence, clinicopathological characteristics and survival of ocular adnexal lymphoma (OAL) in the paediatric population.Methods and analysis In this retrospective case series, the Surveillance, Epidemiology and End Results database was accessed to identify individuals with OAL ≤18 years of age, diagnosed between 1973 and 2015. OAL located in the eyelid, conjunctiva, lacrimal apparatus and orbit were included. Main outcome measures were the age-adjusted incidence rates (IRs) per 1 000 000 population at risk (calculated for the period 2000–2015) and descriptive statistics of demographic and clinicopathological features.Results The IR of paediatric OAL was 0.12 (95% CI 0.08 to 0.16) per 1 000 000. Males (0.15; 95% CI 0.10 to 0.22) and blacks (0.24; 95% CI 0.13 to 0.42) had a higher tendency for OAL development. A total of 55 tumours in 54 children were identified. The majority were localised (78.4%), conjunctival (49.1%) lymphomas. Extranodal marginal zone lymphoma (EMZL, 45.5%, n=25) was the most frequent subtype, followed by diffuse large B-cell lymphoma (DLBCL, 9.1%, n=5), B lymphoblastic lymphoma (7.3%, n=4), follicular lymphoma (5.5%, n=3), Burkitt lymphoma (5.5%, n=3), anaplastic large cell lymphoma (ALCL, 3.6%, n=2), small lymphocytic lymphoma (1.8%, n=1), diffuse large B-cell lymphoma, immunoblastic (1.8%, n=1) and panniculitis-like T-cell lymphoma (1.8%, n=1). Localised, low-grade, conjunctival lymphomas were frequently treated with complete excision with or without radiation, while high-grade and distant tumours usually received chemotherapy. Only 29.1% of paediatric OAL cases were treated with radiation. Three out of five (60%) patients with DLBCL died of lymphoma at a median follow-up of 21 (range 10–86) months, and 1 out of 2 (50%) patients with ALCL died of lymphoma at 23 months from diagnosis.Conclusion OAL in the paediatric population is rare. The majority of OAL are EMZL and are characterised by excellent prognosis. The histological subtype was found to be the main predictor of outcome with cancer-specific deaths observed in patients with DLBCL and ALCL.
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- 2020
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4. Acadesine suppresses TNF-α induced complement component 3 (C3), in retinal pigment epithelial (RPE) cells.
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Nikolaos E Efstathiou, Giannis A Moustafa, Daniel E Maidana, Eleni K Konstantinou, Shoji Notomi, Paulo R T Barbisan, Constantine D Georgakopoulos, Joan W Miller, and Demetrios G Vavvas
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Medicine ,Science - Abstract
RationaleAge-related macular degeneration (AMD) is the most prevalent form of irreversible blindness in the developed world. Aging, inflammation and complement dysregulation affecting the retinal pigment epithelium (RPE), are considered significant contributors in its pathogenesis and several evidences have linked tumor necrosis factor alpha (TNF-α) and complement component 3 (C3) with AMD. Acadesine, an analog of AMP and an AMP-activated protein kinase (AMPK) activator, has been shown to have cytoprotective effects in human clinical trials as well as having anti-inflammatory and anti-vascular exudative effects in animals. The purpose of this study was to evaluate if acadesine is able to suppress TNF-α induced C3 in RPE cells.MethodsARPE-19 and human primary RPE cells were cultured and allowed to grow to confluence. TNF-α was used for C3 induction in the presence or absence of acadesine. Small molecule inhibitors and siRNA were used to determine if acadesine exerts its effect via the extracellular or intracellular pathway and to evaluate the importance of AMPK for these effects. The expression level of C3 was determined by immunoblot analysis.ResultsAcadesine suppresses TNF-α induced C3 in a dose dependent manner. When we utilized the adenosine receptor inhibitor dipyridamole (DPY) along with acadesine, acadesine's effects were abolished, indicating the necessity of acadesine to enter the cell in order to exert it's action. However, pretreatment with 5-iodotubericidin (5-Iodo), an adenosine kinase (AK) inhibitor, didn't prevent acadesine from decreasing TNF-α induced C3 expression suggesting that acadesine does not exert its effect through AMP conversion and subsequent activation of AMPK. Consistent with this, knockdown of AMPK α catalytic subunit did not affect the inhibitory effect of acadesine on TNF-α upregulation of C3.ConclusionsOur results suggest that acadesine suppresses TNF-α induced C3, likely through an AMPK-independent pathway, and could have potential use in complement over activation diseases.
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- 2020
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5. miR-17-3p Exacerbates Oxidative Damage in Human Retinal Pigment Epithelial Cells.
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Bo Tian, Daniel E Maidana, Bernard Dib, John B Miller, Peggy Bouzika, Joan W Miller, Demetrios G Vavvas, and Haijiang Lin
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Medicine ,Science - Abstract
Oxidative stress has been shown to contribute to the development of age-related macular degeneration (AMD). MicroRNAs (miRNA) are small non-coding RNA molecules that function in RNA silencing and post-transcriptional regulation of gene expression. We showed miR-17-3p to be elevated in macular RPE cells from AMD patients and in ARPE-19 cells under oxidative stress. Transfection of miR-17-3p mimic in ARPE-19 induced cell death and exacerbated oxidative lethality that was alleviated by miR-17-3p inhibitor. The expression of antioxidant enzymes manganese superoxide dismutase (MnSOD) and thioredoxin reductase-2 (TrxR2) were suppressed by miR-17-3p mimic and reversed by miR-17-3p inhibitor. These results suggest miR-17-3p aggravates oxidative damage-induced cell death in human RPE cells, while miR-17-3p inhibitor acts as a potential protector against oxidative stress by regulating the expression of antioxidant enzymes.
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- 2016
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6. AMPK-Activated Protein Kinase Suppresses Ccr2 Expression by Inhibiting the NF-κB Pathway in RAW264.7 Macrophages.
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Fumiaki Kumase, Kimio Takeuchi, Yuki Morizane, Jun Suzuki, Hidetaka Matsumoto, Keiko Kataoka, Ahmad Al-Moujahed, Daniel E Maidana, Joan W Miller, and Demetrios G Vavvas
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Medicine ,Science - Abstract
C-C chemokine receptor 2 (Ccr2) is a key pro-inflammatory marker of classic (M1) macrophage activation. Although Ccr2 is known to be expressed both constitutively and inductively, the full regulatory mechanism of its expression remains unclear. AMP-activated protein kinase (AMPK) is not only a master regulator of energy homeostasis but also a central regulator of inflammation. In this study, we sought to assess AMPK's role in regulating RAW264.7 macrophage Ccr2 protein levels in resting (M0) or LPS-induced M1 states. In both M0 and M1 RAW264.7 macrophages, knockdown of the AMPKα1 subunit by siRNA led to increased Ccr2 levels whereas pharmacologic (A769662) activation of AMPK, attenuated LPS-induced increases in Ccr2 expression in an AMPK dependent fashion. The increases in Ccr2 levels by AMPK downregulation were partially reversed by NF-κB inhibition whereas TNF-a inhibition had minimal effects. Our results indicate that AMPK is a negative regulator of Ccr2 expression in RAW264.7 macrophages, and that the mechanism of action of AMPK inhibition of Ccr2 is mediated, in part, through the NF-κB pathway.
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- 2016
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7. Characterization of a spontaneous retinal neovascular mouse model.
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Eiichi Hasegawa, Harry Sweigard, Deeba Husain, Ana M Olivares, Bo Chang, Kaylee E Smith, Amy E Birsner, Robert J D'Amato, Norman A Michaud, Yinan Han, Demetrios G Vavvas, Joan W Miller, Neena B Haider, and Kip M Connor
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Medicine ,Science - Abstract
Vision loss due to vascular disease of the retina is a leading cause of blindness in the world. Retinal angiomatous proliferation (RAP) is a subgroup of neovascular age-related macular degeneration (AMD), whereby abnormal blood vessels develop in the retina leading to debilitating vision loss and eventual blindness. The novel mouse strain, neoretinal vascularization 2 (NRV2), shows spontaneous fundus changes associated with abnormal neovascularization. The purpose of this study is to characterize the induction of pathologic angiogenesis in this mouse model.The NRV2 mice were examined from postnatal day 12 (p12) to 3 months. The phenotypic changes within the retina were evaluated by fundus photography, fluorescein angiography, optical coherence tomography, and immunohistochemical and electron microscopic analysis. The pathological neovascularization was imaged by confocal microscopy and reconstructed using three-dimensional image analysis software.We found that NRV2 mice develop multifocal retinal depigmentation in the posterior fundus. Depigmented lesions developed vascular leakage observed by fluorescein angiography. The spontaneous angiogenesis arose from the retinal vascular plexus at postnatal day (p)15 and extended toward retinal pigment epithelium (RPE). By three months of age, histological analysis revealed encapsulation of the neovascular lesion by the RPE in the photoreceptor cell layer and subretinal space.The NRV2 mouse strain develops early neovascular lesions within the retina, which grow downward towards the RPE beginning at p15. This retinal neovascularization model mimics early stages of human retinal angiomatous proliferation (RAP) and will likely be a useful in elucidating targeted therapeutics for patients with ocular neovascular disease.
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- 2014
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8. EGF-like-domain-7 is required for VEGF-induced Akt/ERK activation and vascular tube formation in an ex vivo angiogenesis assay.
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Kimio Takeuchi, Ryoji Yanai, Fumiaki Kumase, Yuki Morizane, Jun Suzuki, Maki Kayama, Katarzyna Brodowska, Mitsuru Nakazawa, Joan W Miller, Kip M Connor, and Demetrios G Vavvas
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Medicine ,Science - Abstract
EGFL7 is a secreted angiogenic factor, which in contrast to the well-known secreted angiogenic molecules VEGF and FGF-2, is almost exclusively expressed by endothelial cells and may act in an autocrine fashion. Prior studies have shown EGFL7 to mediate its angiogenic effects by interfering with the Notch pathway and/or via the intronic miR126. Less is known about its effects on VEGF signaling. We wanted to investigate the role of epidermal growth factor-like domain 7 (EGFL7) in VEGF-driven angiogenesis using an ex vivo Matrigel-embedded mouse eye cup assay and siRNA mediated knockdown of EGFL7 by siRNA. Our results suggested that VEGF-induced vascular tube formation was significantly impaired after siRNA downregulation of EGFL7. In addition, knockdown of EGFL7 suppressed VEGF upregulation of phospho-Akt and phospho-Erk(1/2) in endothelial cells, but did not alter VEGFR phosphorylation and neuropilin-1 protein expression or miR126 expression. Thus, in conclusion, EGFL7 is required for VEGF upregulation of the Akt/Erk (1/2) pathway during angiogenesis, and may represent a new therapeutic target in diseases of pathological neovascularization.
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- 2014
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9. Aminoimidazole carboxamide ribonucleotide (AICAR) inhibits the growth of retinoblastoma in vivo by decreasing angiogenesis and inducing apoptosis.
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Sofia Theodoropoulou, Katarzyna Brodowska, Maki Kayama, Yuki Morizane, Joan W Miller, Evangelos S Gragoudas, and Demetrios G Vavvas
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Medicine ,Science - Abstract
5-Aminoimidazole-4-carboxamide-1-β-4-ribofuranoside (AICAR), an analog of AMP is widely used as an activator of AMP-kinase (AMPK), a protein that regulates the responses of the cell to energy change. Recently, we showed that AICAR-induced AMPK activation inhibits the growth of retinoblastoma cells in vitro by decreasing cyclins and by inducing apoptosis and S-phase arrest. In this study, we investigated the effects of AMPK activator AICAR on the growth of retinoblastoma in vivo. Intraperitoneal injection of AICAR resulted in 48% growth inhibition of Y79 retinoblastoma cell tumors in mice. Tumors isolated from mice treated with AICAR had decreased expression of Ki67 and increased apoptotic cells (TUNEL positive) compared with the control. In addition, AICAR treatment suppressed significantly tumor vessel density and macrophage infiltration. We also showed that AICAR administration resulted in AMPK activation and mTOR pathway inhibition. Paradoxically observed down-regulation of p21, which indicates that p21 may have a novel function of an oncogene in retinoblastoma tumor. Our results indicate that AICAR treatment inhibited the growth of retinoblastoma tumor in vivo via AMPK/mTORC1 pathway and by apoptogenic, anti-proliferative, anti-angiogenesis mechanism. AICAR is a promising novel non-chemotherapeutic drug that may be effective as an adjuvant in treating Retinoblastoma.
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- 2013
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10. Etanercept, a widely used inhibitor of tumor necrosis factor-α (TNF-α), prevents retinal ganglion cell loss in a rat model of glaucoma.
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Miin Roh, Yan Zhang, Yusuke Murakami, Aristomenis Thanos, Sung Chul Lee, Demetrios G Vavvas, Larry I Benowitz, and Joan W Miller
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Medicine ,Science - Abstract
Visual loss in glaucoma is associated with pathological changes in retinal ganglion cell (RGC) axons and a slow decline in the RGC population. Age and elevated intraocular pressure (IOP) are the main risk factors for glaucomatous loss of vision. Several studies have implicated the proinflammatory cytokine tumor necrosis factor-α (TNF-α) as a link between elevated IOP and RGC death, but the cellular source of TNF-α and its causative role in RGC death remain uncertain. Here, using a rat model of glaucoma, we investigated the source of elevated TNF-α and examined whether Etanercept, a TNF-α blocker that is in common clinical use for other indications, is protective against RGC death.Episcleral vein cauterization (EVC) caused intraocular pressure (IOP) to be elevated for at least 28 days. IOP elevation resulted in a dramatic increase in TNF-α levels within a few days, axonal degeneration, and a 38% loss of RGCs by 4 weeks. Immunostaining coupled with confocal microscopy showed that OHT induced robust induction of TNF-α in Iba-1-positive microglia around the optic nerve head (ONH). Despite persistent elevation of IOP, Etanercept reduced microglial activation, TNF-α levels, axon degeneration in the optic nerve, and the loss of RGCs.Ocular hypertension (OHT) triggers an inflammatory response characterized by the appearance of activated microglia around the ONH that express TNF-α. Blocking TNF-α activity with a clinically approved agent inhibits this microglial response and prevents axonal degeneration and loss of RGCs. These findings suggest a new treatment strategy for glaucoma using TNF-α antagonists or suppressors of inflammation.
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- 2012
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11. Tauroursodeoxycholic acid (TUDCA) protects photoreceptors from cell death after experimental retinal detachment.
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Dimosthenis Mantopoulos, Yusuke Murakami, Jason Comander, Aristomenis Thanos, Miin Roh, Joan W Miller, and Demetrios G Vavvas
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Medicine ,Science - Abstract
Detachment of photoreceptors from the underlying retinal pigment epithelium is seen in various retinal disorders such as retinal detachment and age-related macular degeneration and leads to loss of photoreceptors and vision. Pharmacologic inhibition of photoreceptor cell death may prevent this outcome. This study tests whether systemic administration of tauroursodeoxycholic acid (TUDCA) can protect photoreceptors from cell death after experimental retinal detachment in rodents.Retinal detachment was created in rats by subretinal injection of hyaluronic acid. The animals were treated daily with vehicle or TUDCA (500 mg/kg). TUNEL staining was used to evaluate cell death. Photoreceptor loss was evaluated by measuring the relative thickness of the outer nuclear layer (ONL). Macrophage recruitment, oxidative stress, cytokine levels, and caspase levels were also quantified. Three days after detachment, TUDCA decreased the number of TUNEL-positive cells compared to vehicle (651±68/mm(2) vs. 1314±68/mm(2), P = 0.001) and prevented the reduction of ONL thickness ratio (0.84±0.03 vs. 0.65±0.03, P = 0.002). Similar results were obtained after 5 days of retinal detachment. Macrophage recruitment and expression levels of TNF-a and MCP-1 after retinal detachment were not affected by TUDCA treatment, whereas increases in activity of caspases 3 and 9 as well as carbonyl-protein adducts were almost completely inhibited by TUDCA treatment.Systemic administration of TUDCA preserved photoreceptors after retinal detachment, and was associated with decreased oxidative stress and caspase activity. TUDCA may be used as a novel therapeutic agent for preventing vision loss in diseases that are characterized by photoreceptor detachment.
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- 2011
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12. The <scp>NLRP3</scp> inflammasome – interleukin 1β axis in uveal melanoma
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Victor S. M. C. Correa, Nikolaos E. Efstathiou, Dimitrios P. Ntentakis, Zhen Yu, Toshio Narimatsu, Evangelos Gragoudas, Ivana K. Kim, and Demetrios G. Vavvas
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General Biochemistry, Genetics and Molecular Biology - Published
- 2023
13. Restoration of Vision in Severe, Cicatricial, Ocular Surface Disease With the Boston Keratoprosthesis Type II
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Chhavi Saini, Teresa C. Chen, Lucy H. Young, Demetrios G. Vavvas, Mark Vangel, George N. Papaliodis, Shizuo Mukai, Angela V. Turalba, Douglas J. Rhee, David M. Wu, Dean Eliott, John B. Miller, Brian J. Song, Lucy Q. Shen, Louis R. Pasquale, and James Chodosh
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Cornea ,Prosthesis Implantation ,Ophthalmology ,Humans ,Glaucoma ,Prostheses and Implants ,Corneal Diseases ,Retrospective Studies - Abstract
To assess clinical outcomes of patients with severe, cicatricial ocular surface disease (OSD) implanted with the currently marketed design of the Boston keratoprosthesis type II (BK2).Retrospective cohort study.Records of consecutive patients undergoing BK2 implantation from June 2009 to March 2021 were assessed for postoperative visual acuity, postoperative complications, device replacement, and additional surgeries.Fifty-six eyes of 53 patients with a mean follow-up of 45.8 months (range, 0.2-134.7 months) were included. Stevens-Johnson syndrome/toxic epidermal necrolysis was the most common indication (49.1%), followed by mucous membrane pemphigoid (39.6%) and other OSD (11.3%). Visual acuity improved from logMAR 2.2 ± 0.5 preoperatively to 1.5 ± 1.2 at final follow-up. Of 56 eyes, 50 saw ≥20/200 at some point postoperatively. Of the eyes with a follow-up of more than 5 years, 50.0% retained a visual acuity of ≥20/200 at their final follow-up. The most common complications over the entire postoperative course (mean ∼4 years) were de novo or worsening glaucoma (41.1%), choroidal effusions (30.3%), retinal detachment (25.0%), and end-stage glaucoma (25.0%). In a univariate analysis, patients who experienced irreversible loss of ≥20/200 visual acuity were more likely to have been previously implanted with an older design of BK2, less likely to be on preoperative systemic immunosuppressive therapy, and less likely to have undergone concurrent glaucoma tube implantation, compared to patients who retained ≥20/200 acuity (P.04 for all).Advances in device design and postoperative care have made implantation of BK2 a viable option for corneal blindness in the setting of severe cicatricial OSD.
- Published
- 2022
14. The Effect of Sample Medication Use on Subsequent Anti-VEGF Agent Selection for Neovascular Age-Related Macular Degeneration
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Joan W. Miller, Mary E. Aronow, Tedi Begaj, John B Miller, Lucy H. Young, Rachel M. Huckfeldt, Jan A. Kylstra, Demetrios G. Vavvas, Deeba Husain, Dean Eliott, David M. Wu, Shizuo Mukai, Leo A. Kim, Evan Chen, Sachi Patil, Lucia Sobrin, Karen M Wai, Ravi Parikh, Evangelos S. Gragoudas, and Nimesh A. Patel
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Vascular Endothelial Growth Factor A ,medicine.medical_specialty ,Visual acuity ,Bevacizumab ,Recombinant Fusion Proteins ,Angiogenesis Inhibitors ,Macular Degeneration ,Age related ,Internal medicine ,Ranibizumab ,medicine ,Humans ,Aflibercept ,Retrospective Studies ,Anti vegf ,business.industry ,General Medicine ,Macular degeneration ,medicine.disease ,Ophthalmology ,Receptors, Vascular Endothelial Growth Factor ,Intravitreal Injections ,medicine.symptom ,business ,medicine.drug ,Cohort study - Abstract
Purpose: To examine the effect of medication sample use (ranibizumab or aflibercept) on future anti-vascular endothelial growth factor (VEGF) agent selection in neovascular age-related macular degeneration (nvAMD). Design: Retrospective cohort study. Methods: nvAMD patients who underwent an initial anti-VEGF injection with a sample medication were compared to nvAMD control patients who never received a medication sample. Charts from 2017 through 2020 were reviewed for data regarding demographics, anti-VEGF agent selection, and visual acuity outcomes for both groups. Anti-VEGF agent selection for the first four injections and at one year were examined in both the sample and control groups. Results: Adherence to the initial agent was high between first and subsequent injections (2nd, 3rd, 4th injection, and 1 year) in both sample (96.2%, 95.9%, 91.9%, 93.4%, respectively) and control groups (98.1%, 94.2%, 94.9%, 87.8%, respectively). Bevacizumab usage was significantly lower among eyes receiving samples relative to controls at the second (1.9% vs. 38.7%, p
- Published
- 2022
15. A novel sustained release therapy of combined VEGF and TNF-α inhibitors leads to pan-ocular protection for months after severe ocular trauma
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Chengxin Zhou, Fengyang Lei, Pui-Chuen Hui, Natalie Wolkow, Claes H. Dohlman, Demetrios G. Vavvas, James Chodosh, and Eleftherios I. Paschalis
- Abstract
PurposeTo develop a clinically feasible and practical therapy for multi-ocular protection following ocular injury by using a thermosensitive drug delivery system (DDS) for sustained delivery of TNF-α and VEGF inhibitors to the eye.MethodsA thermosensitive, biodegradable hydrogel DDS (PLGA-PEG-PLGA triblock polymer) loaded with 0.7mg of adalimumab and 1.4 mg of aflibercept was injected subconjunctivally in Dutch-belted pigmented rabbits after corneal alkali injury. The polymer was tuned to transition from liquid to gel upon contact with body temperature without need of a catalyst. Control rabbits received 2mg of IgG loaded DDS or 1.4mg aflibercept loaded DDS. Animals were followed for 3 months and assessed for tolerability and prevention of corneal neovascularization (NV), improvement of corneal re-epithelialization, inhibition of retinal ganglion cell (RGC) and optic nerve axon loss, and inhibition of immune cell infiltration into the cornea. Drug release kinetics was assessedin vivousing aqueous humor protein analysis.ResultsA single subconjunctival administration of dual anti-TNFα/anti-VEGF DDS achieved sustained 3-month delivery of antibodies to the anterior chamber, iris, ciliary body, and retina. Administration after corneal alkali burn suppressed CD45+immune cell infiltration into the cornea, completely inhibited cornea NV for 3 months, accelerated corneal re-epithelialization and wound healing, and prevented RGC and optic nerve axon loss at 3 months. In contrast, anti-VEGF alone or IgG DDS treatment led to persistent corneal epithelial defect, increased infiltration of CD45+immune cells into the cornea, and significant loss of RGCs and optic nerve axons at 3 months. Aqueous humor protein analysis showed first-order release kinetics without adverse effects at the injection site.ConclusionSustained concomitant inhibition of TNF-α and VEGF using a biodegradable, slow-release thermosensitive DDS provides significant ocular protection and prevents corneal neovascularization and irreversible damage to retina and optic nerve after corneal alkali injury. This therapeutic approach has the potential to dramatically improve the outcomes of severe ocular injuries in patients.
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- 2023
16. Acute Syphilitic Posterior Placoid Chorioretinitis With Subfoveal Choroidal Neovascularization Managed With Anti-VEGF Therapy
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Karen M. Wai, Dan Gong, Marianeli Rodriguez, Emmett T. Cunningham Jr, Demetrios G. Vavvas, and Dean Eliott
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Article - Abstract
Purpose: We describe the development and management of choroidal neovascularization (CNV) in a patient with acute syphilitic posterior placoid chorioretinitis (ASPPC). Methods: A retrospective case review is presented. Results: A 66-year-old man presented with unilateral blurry vision. He had a history of systemic syphilis infection twice, the last diagnosed 15 years before presentation and treated with intravenous ceftriaxone, resulting in seroreversion of an initially positive rapid plasma reagin (RPR). Examination revealed ASPPC with subfoveal CNV. Repeat testing revealed an RPR titer of 1:16 384. He was treated with 6 monthly intravitreal injections of bevacizumab and systemic antibiotics, resulting in resolution of his ASPPC and regression of his CNV. Conclusions: CNV is a rare complication of ASPPC. Multimodal imaging can be useful to suggest the diagnosis, and prompt treatment with systemic antibiotics and intravitreal anti-vascular endothelial growth factor agents can lead to resolution of ASPPC and regression of CNV, respectively.
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- 2022
17. Endoscopic Cyclophotocoagulation in Boston Keratoprosthesis Type II
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Lucy H. Young, Christine Xu, Teresa C. Chen, Dean Eliott, Demetrios G. Vavvas, Michael M. Lin, James Chodosh, Shizuo Mukai, and Lucy Q. Shen
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Pars plana ,medicine.medical_specialty ,Intraocular pressure ,genetic structures ,medicine.medical_treatment ,Visual Acuity ,Glaucoma ,Vitrectomy ,Cup-to-disc ratio ,Corneal Diseases ,Cornea ,Ophthalmology ,medicine ,Humans ,Retrospective review ,business.industry ,Ciliary Body ,Prostheses and Implants ,General Medicine ,medicine.disease ,eye diseases ,body regions ,medicine.anatomical_structure ,sense organs ,Eyelid ,Boston keratoprosthesis ,business - Abstract
This retrospective review of 7 cases demonstrates that endoscopic cyclophotocoagulation via eyelid incision and enlargement of pars plana vitrectomy entry sites can lower intraocular pressure in eyes with history of Boston keratoprosthesis Type II surgery.
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- 2022
18. Referable Macular Hemorrhage—A Clinically Meaningful Screening Target in Newborn Infants. Position Statement of the Association of Pediatric Retina Surgeons
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Edward H. Wood, Antonio Capone, Kimberly A. Drenser, Audinal Berrocal, G. Baker Hubbard, Natalia F. Callaway, Andres Kychenthal, Anna Ells, Clio A. Harper, Cagri Giray Besirli, Caroline R. Baumal, Demetrios G. Vavvas, Emmanuel Y. Chang, Eric D. Nudleman, Irena Tsui, Jonathan Sears, Lejla Vajzovic, Mary E. Hartnett, Michael J. Shapiro, Polly A. Quiram, Sengul Ozdek, Shunjil Kusaka, Wei-Chi Wu, and Michael T. Trese
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Surgeons ,Neonatal Screening ,Eye Diseases ,Infant, Newborn ,Humans ,Infant ,Retinal Hemorrhage ,Child ,Retina - Abstract
Universal newborn eye screening facilitates early diagnosis of ocular abnormalities and mitigates vision loss. “Referral warranted” eye disease is present at birth in about 5.5% of term infants, with “macular hemorrhage impinging on the fovea” representing about 50% of referral warranted disease. The Association of Pediatric Retina Surgeons held a symposium on February 9, 2021 that culminated in a position statement on “referable macular hemorrhage” (RMH) in newborn infants. RMH is meaningful in that in can cause amblyopia through deprivation, can be readily captured with wide-angle photography in a safe and efficient manner, and may lead to early intervention with mitigation of vision loss. [ Ophthalmic Surg Lasers Imaging Retina . 2022;53:3–6.]
- Published
- 2022
19. Ocular Toxoplasmosis: A Review of Current Literature
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Neal S, Patel and Demetrios G, Vavvas
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Ophthalmology ,Humans ,Toxoplasmosis, Ocular - Published
- 2022
20. Widefield Swept-Source OCT Angiography Metrics Associated with the Development of Diabetic Vitreous Hemorrhage
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Itika Garg, Dean Eliott, Joan W. Miller, Ying Cui, Inês Laíns, Yifan Lu, David M. Wu, Edward S Lu, Leo A. Kim, Ying Zhu, Jay C Wang, John B Miller, Rebecca Zeng, Rongrong Le, Raviv Katz, Demetrios G. Vavvas, and Deeba Husain
- Subjects
0303 health sciences ,medicine.medical_specialty ,genetic structures ,Proportional hazards model ,business.industry ,Hazard ratio ,Diabetic retinopathy ,Odds ratio ,medicine.disease ,Lower risk ,eye diseases ,Confidence interval ,03 medical and health sciences ,Ophthalmology ,0302 clinical medicine ,Vitreous hemorrhage ,030221 ophthalmology & optometry ,medicine ,sense organs ,Prospective cohort study ,business ,030304 developmental biology - Abstract
Purpose To investigate the association among widefield swept-source (SS) OCT angiography (OCTA) metrics and systemic parameters and vitreous hemorrhage (VH) occurrence in eyes with proliferative diabetic retinopathy (PDR). Design Prospective, observational study. Participants Fifty-five eyes from 45 adults with PDR, with no history of VH, followed up for at least 3 months. Methods All patients underwent widefield SS OCTA (Montage 15 × 15 mm and high-definition (HD)-51 line scan) imaging. Images were evaluated independently by 2 graders for quantitative and qualitative widefield SS OCTA metrics defined a priori. Systemic and ocular parameters and widefield SS OCTA metrics were screened using least absolute shrinkage and selection operator and logistic or Cox regression for variable selection. Firth’s bias-reduced logistic regression models (outcome, occurrence of VH) and Cox regression models (outcome, time to occurrence of VH) were used to identify parameters associated with VH occurrence. Main Outcome Measures Occurrence of VH. Results Over a median follow-up of 363 days (range, 28–710 days), 13 of 55 PDR eyes (24%) demonstrated VH during the follow-up period. Presence of extensive neovascularizations (odds ratio, 8.05; 95% confidence interval [CI], 1.43–58.56; P = 0.02), defined as neovascularizations with total area of more than 4 disc diameters, and forward neovascularizations (odds ratio, 5.42; 95% CI, 1.26–35.16; P = 0.02) that traversed the posterior hyaloid face into the vitreous were associated with the occurrence of VH. The presence of flat neovascularizations (odds ratio, 0.25; 95% CI, 0.04–1.01; P = 0.05) confined to the posterior hyaloid face was associated with a lower risk of VH with borderline significance. Similarly, presence of extensive neovascularizations (hazard ratio, 18.24; 95% CI, 3.51–119.47; P Conclusions Widefield SS OCTA is useful for evaluating neovascularizations and their relationship with the vitreous. The presence of forward and extensive neovascularizations was associated with the occurrence of VH in patients with PDR. Larger samples and longer follow-up are needed to verify the risk factors and imaging biomarkers for diabetic VH.
- Published
- 2021
21. ALTITUDE-ASSOCIATED INTRAOCULAR PRESSURE CHANGES IN A GAS-FILLED EYE
- Author
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Demetrios G. Vavvas, Xiaohong Chen, and William Foulsham
- Subjects
Male ,Pars plana ,Intraocular pressure ,medicine.medical_specialty ,Aircraft ,genetic structures ,medicine.medical_treatment ,Vitrectomy ,01 natural sciences ,Article ,03 medical and health sciences ,0302 clinical medicine ,Altitude ,Ophthalmology ,Humans ,Medicine ,In patient ,0101 mathematics ,Ocular pain ,Intraocular Pressure ,Fluorocarbons ,business.industry ,010102 general mathematics ,Retinal Detachment ,Retinal detachment ,General Medicine ,Middle Aged ,medicine.disease ,eye diseases ,medicine.anatomical_structure ,Male patient ,030221 ophthalmology & optometry ,Gases ,sense organs ,business - Abstract
Purpose Intraocular gases are commonly used in vitreoretinal surgery. Patients are routinely advised against air travel before the complete absorption of intraocular gas. Consequently, reports on air travel in patients with large intraocular gas bubbles are highly unusual. Here, we report the intraocular pressure changes of a patient ascending to an altitude of 2,600 feet in a helicopter with a 50% fill perfluoropropane (C3F8) gas bubble in his left eye. Methods Case report and literature review. Results A 61-year-old male patient underwent pars plana vitrectomy for a rhegmatogenous retinal detachment, with fluid-gas exchange using 16% C3F8. With a 50% fill bubble in the left eye, the patient took a short helicopter trip ascending to a maximum altitude of 2,600 feet. Before take-off, intraocular pressure in the operated eye was 14 mmHg. The average increase in intraocular pressure was 10.8 mmHg per 1,000 feet of ascent, with a maximum recorded intraocular pressure of 42 mmHg. The patient denied both ocular pain and loss of vision but did report changes in the appearance of the gas bubble meniscus at 2,100 feet. Conclusion Short-term low-altitude air travel may be tolerated by some patients with intraocular gas in situ. Further studies are required to define the conditions by which patients with gas bubbles may fly safely.
- Published
- 2021
22. Necroptosis and Neuroinflammation in Retinal Degeneration
- Author
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Yan, Tao, Yusuke, Murakami, Demetrios G, Vavvas, and Koh-Hei, Sonoda
- Subjects
General Neuroscience - Abstract
Necroptosis mediates the chronic inflammatory phenotype in neurodegeneration. Receptor-interacting protein kinase (RIPK) plays a pivotal role in the induction of necroptosis in various cell types, including microglia, and it is implicated in diverse neurodegenerative diseases in the central nervous system and the retina. Targeting RIPK has been proven beneficial for alleviating both neuroinflammation and degeneration in basic/preclinical studies. In this review, we discuss the role of necroptosis in retinal degeneration, including (1) the molecular pathways involving RIPK, (2) RIPK-dependent microglial activation and necroptosis, and (3) the interactions between necroptosis and retinal neuroinflammation/degeneration. This review will contribute to a renewed focus on neuroinflammation induced by necroptosis and to the development of anti-RIPK drugs against retinal degeneration.
- Published
- 2022
23. Systemic Complement Activation Profiles in Nonexudative Age-Related Macular Degeneration: A Systematic Review
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Jonathan B, Lin, Stylianos, Serghiou, Joan W, Miller, and Demetrios G, Vavvas
- Abstract
To evaluate whether differences exist in systemic complement activation profiles in patients with early to intermediate nonexudative age-related macular degeneration (AMD) or geographic atrophy (GA) compared with control participants without AMD.Complement inhibition has emerged as a therapeutic strategy for GA, although clinical trials to date have yielded mixed results. Despite these efforts, no clear consensus exists regarding what portions of the complement pathway are dysregulated in AMD or when this dysregulation occurs relative to AMD stage. Although past studies have compared systemic complement activation profiles in patients with AMD versus in control participants without AMD, differences in AMD case definition and differing analytical approaches complicate their interpretation.We performed a systematic review by identifying articles from database inception through October 11, 2020, that reported systemic complement activation profiles in patients with early or intermediate nonexudative AMD or GA versus control participants without AMD by searching PubMed, Google Scholar, and Embase. Risk of bias was assessed using a modified Newcastle-Ottawa score.The 8 reviewed studies included 2131 independent participants. Most studies report significantly higher systemic levels of products associated with complement activation and significantly lower systemic levels of products associated with complement inhibition in patients with early and advanced nonexudative AMD compared with control participants without AMD.Evidence suggests that systemic complement overactivation is a feature of early or intermediate and advanced nonexudative AMD. However, given significant heterogeneity, these findings are not conclusive and warrant further investigation.
- Published
- 2022
24. Systemic dyslipidemia in age-related macular degeneration: an updated systematic review and meta-analysis
- Author
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Brandon Li, Deborah Goss, Joan W. Miller, Jonathan B. Lin, and Demetrios G. Vavvas
- Subjects
General Medicine - Published
- 2023
25. Neuroprotective effects and mechanisms of action of nicotinamide mononucleotide (NMN) in a photoreceptor degenerative model of retinal detachment
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Xiaohong Chen, J.B. Lee, Lin Lu, Paulo Rodolfo Tagliari Barbisan, Kenji Ishihara, David A. Sinclair, Yasuhiro Iesato, Takashi Ueta, Zhen Yu, Konstantina A. Togka, João A. Amorim, Demetrios G. Vavvas, and Giannis A. Moustafa
- Subjects
Lipopolysaccharides ,Aging ,nicotinamide mononucleotide ,Stimulation ,Apoptosis ,Nicotinamide adenine dinucleotide ,medicine.disease_cause ,Neuroprotection ,Cell Line ,Protein Carbonylation ,chemistry.chemical_compound ,Mice ,SIRT1 ,Sirtuin 1 ,NAD+ ,Glial Fibrillary Acidic Protein ,medicine ,In Situ Nick-End Labeling ,Animals ,Outer nuclear layer ,Nicotinamide mononucleotide ,photoreceptor degeneration ,TUNEL assay ,CD11b Antigen ,Chemistry ,Macrophages ,Retinal Degeneration ,Retinal Detachment ,Membrane Proteins ,Cell Biology ,NAD ,Cell biology ,Oxidative Stress ,medicine.anatomical_structure ,Neuroprotective Agents ,neuroprotection ,NAD+ kinase ,Oxidative stress ,Heme Oxygenase-1 ,Priority Research Paper ,Photoreceptor Cells, Vertebrate - Abstract
Currently, no pharmacotherapy has been proven effective in treating photoreceptor degeneration in patients. Discovering readily available and safe neuroprotectants is therefore highly sought after. Here, we investigated nicotinamide mononucleotide (NMN), a precursor of nicotinamide adenine dinucleotide (NAD+), in a retinal detachment (RD) induced photoreceptor degeneration. NMN administration after RD resulted in a significant reduction of TUNEL+ photoreceptors, CD11b+ macrophages, and GFAP labeled glial activation; a normalization of protein carbonyl content (PCC), and a preservation of the outer nuclear layer (ONL) thickness. NMN administration significantly increased NAD+ levels, SIRT1 protein expression, and heme oxygenase-1 (HO-1) expression. Delayed NMN administration still exerted protective effects after RD. Mechanistic in vitro studies using 661W cells revealed a SIRT1/HO-1 signaling as a downstream effector of NMN-mediated protection under oxidative stress and LPS stimulation. In conclusion, NMN administration exerts neuroprotective effects on photoreceptors after RD and oxidative injury, suggesting a therapeutic avenue to treating photoreceptor degeneration.
- Published
- 2020
26. Treatment and prevention of pathological mitochondrial dysfunction in retinal degeneration and in photoreceptor injury
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Walter H. Moos, Douglas V. Faller, Ioannis P. Glavas, David N. Harpp, Natalia Kamperi, Iphigenia Kanara, Krishna Kodukula, Anastasios N. Mavrakis, Julie Pernokas, Mark Pernokas, Carl A. Pinkert, Whitney R. Powers, Konstantina Sampani, Kosta Steliou, Constantin Tamvakopoulos, Demetrios G. Vavvas, Robert J. Zamboni, and Xiaohong Chen
- Subjects
Pharmacology ,Carnitine ,Retinal Degeneration ,Infant, Newborn ,Humans ,Photoreceptor Cells ,Biochemistry ,Retina ,Mitochondria - Abstract
Pathological deterioration of mitochondrial function is increasingly linked with multiple degenerative illnesses as a mediator of a wide range of neurologic and age-related chronic diseases, including those of genetic origin. Several of these diseases are rare, typically defined in the United States as an illness affecting fewer than 200,000 people in the U.S. population, or about one in 1600 individuals. Vision impairment due to mitochondrial dysfunction in the eye is a prominent feature evident in numerous primary mitochondrial diseases and is common to the pathophysiology of many of the familiar ophthalmic disorders, including age-related macular degeneration, diabetic retinopathy, glaucoma and retinopathy of prematurity - a collection of syndromes, diseases and disorders with significant unmet medical needs. Focusing on metabolic mitochondrial pathway mechanisms, including the possible roles of cuproptosis and ferroptosis in retinal mitochondrial dysfunction, we shed light on the potential of α-lipoyl-L-carnitine in treating eye diseases. α-Lipoyl-L-carnitine is a bioavailable mitochondria-targeting lipoic acid prodrug that has shown potential in protecting against retinal degeneration and photoreceptor cell loss in ophthalmic indications.
- Published
- 2022
27. Neuroprotection for Age-Related Macular Degeneration
- Author
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Jonathan B. Lin, Yusuke Murakami, Joan W. Miller, and Demetrios G. Vavvas
- Subjects
General Medicine - Abstract
Age-related macular degeneration (AMD) is a leading cause of blindness worldwide. Early to intermediate AMD is characterized by the accumulation of lipid- and protein-rich drusen. Late stages of the disease are characterized by the development of choroidal neovascularization, termed "exudative" or "neovascular AMD," or retinal pigment epithelium (RPE) cell and photoreceptor death, termed "geographic atrophy" (GA) in advanced nonexudative AMD. Although we have effective treatments for exudative AMD in the form of anti-VEGF agents, they have no role for patients with GA. Neuroprotection strategies have emerged as a possible way to slow photoreceptor degeneration and vision loss in patients with GA. These approaches include reduction of oxidative stress, modulation of the visual cycle, reduction of toxic molecules, inhibition of pathologic protein activity, prevention of cellular apoptosis or programmed necrosis (necroptosis), inhibition of inflammation, direct activation of neurotrophic factors, delivery of umbilical tissue-derived cells, and RPE replacement. Despite active investigation in this area and significant promise based on preclinical studies, many clinical studies have not yielded successful results. We discuss selected past and current neuroprotection trials for AMD, highlight the lessons learned from these past studies, and discuss our perspective regarding remaining questions that must be answered before neuroprotection can be successfully applied in the field of AMD research.
- Published
- 2022
28. Circulating inflammatory monocytes oppose microglia and contribute to cone cell death in retinitis pigmentosa
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Jun Funatsu, Yusuke Murakami, Shotaro Shimokawa, Shunji Nakatake, Kohta Fujiwara, Ayako Okita, Masatoshi Fukushima, Kensuke Shibata, Noriko Yoshida, Yoshito Koyanagi, Masato Akiyama, Shoji Notomi, Shintaro Nakao, Toshio Hisatomi, Atsunobu Takeda, Eleftherios I Paschalis, Demetrios G Vavvas, Yasuhiro Ikeda, and Koh-Hei Sonoda
- Subjects
sense organs ,Article - Abstract
Retinitis pigmentosa (RP) is an intractable inherited disease that primarily affects the rods through gene mutations followed by secondary cone degeneration. This cone-related dysfunction can lead to impairment of daily life activities, and ultimately blindness in patients with RP. Paradoxically, microglial neuroinflammation contributes to both protection against and progression of RP, but it is unclear which population(s)— tissue-resident microglia and/or peripheral monocyte-derived macrophages (mφ)— are implicated in the progression of the disease. Here, we show that circulating blood inflammatory monocytes (IMo) are key effector cells that mediate cone cell death in RP. Attenuation of IMo and peripherally engrafted mφ by Ccl2 deficiency or immune modulation via intravenous nanoparticle treatment suppressed cone cell death in rd10 mice, an animal model of RP. In contrast, the depletion of resident microglia by a colony-stimulating factor 1 receptor inhibitor exacerbated cone cell death in the same model. In human patients with RP, IMo was increased and correlated with disease progression. These results suggest that peripheral IMo is a potential target to delay cone cell death and prevent blindness in RP.
- Published
- 2022
29. A quantitative comparison of four optical coherence tomography angiography devices in healthy eyes
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Ying Cui, Rebecca Zeng, Demetrios G. Vavvas, Yifan Lu, Raviv Katz, Ying Zhu, Leo A. Kim, Joan W. Miller, Jay C Wang, Edward S Lu, John B Miller, and Deeba Husain
- Subjects
genetic structures ,business.industry ,Intraclass correlation ,Image quality ,Repeated measures design ,Optical coherence tomography angiography ,Foveal avascular zone ,Fractal analysis ,eye diseases ,Sensory Systems ,Skeletonization ,Cellular and Molecular Neuroscience ,Ophthalmology ,Research studies ,sense organs ,Nuclear medicine ,business ,Mathematics - Abstract
Optical coherence tomography angiography (OCT-A) is a novel imaging modality for the diagnosis of chorioretinal diseases. A number of FDA-approved OCT-A devices are currently commercially available, each with unique algorithms and scanning protocols. Although several published studies have compared different combinations of OCT-A machines, there is a lack of agreement on the consistency of measurements across OCT-A devices. Therefore, we conducted a prospective quantitative comparison of four available OCT-A platforms. Subjects were scanned on four devices: Optovue RTVue-XR, Heidelberg Spectralis OCT2 module, Zeiss Plex Elite 9000 Swept-Source OCT, and Topcon DRI-OCT Triton Swept-Source OCT. 3 mm × 3 mm images were utilized for analysis. Foveal avascular zone (FAZ) area was separately and independently measured by two investigators. Fractal dimension (FD), superficial capillary plexus (SCP), and deep capillary plexus (DCP) vessel densities (VD) were calculated from binarized images using the Fiji image processing software. SCP and DCP VD were further calculated after images were skeletonized. Repeated measures ANOVA, post hoc tests, and interclass correlation coefficient (ICC) were performed for statistical analysis. Sixteen healthy eyes from sixteen patients were scanned on the four devices. Images of five eyes from the Triton device were excluded due to poor image quality; thus, the authors performed two sets comparisons, one with and one without the Triton machine. FAZ area showed no significant difference across devices with an ICC of > 95%. However, there were statistically significant differences for SCP and DCP VD both before and after skeletonization (p < 0.05). Fractal analysis revealed no significant difference of FD at the SCP; however, a statistically significant difference was found for FD at the DCP layer (p < 0.05). The results showed that FAZ measurements were consistent across all four devices, while significant differences in VD and FD measurements existed. Therefore, we suggest that for both clinical follow-up and research studies, FAZ area is a useful parameter for OCT-A image analysis when measurements are made on different machines, while VD and FD show significant variability when measured across devices.
- Published
- 2020
30. Different Scan Protocols Affect the Detection Rates of Diabetic Retinopathy Lesions by Wide-Field Swept-Source Optical Coherence Tomography Angiography
- Author
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Deeba Husain, Jay C Wang, Ying Cui, Demetrios G. Vavvas, David Wu, Dean Eliott, Joan W. Miller, Raviv Katz, Leo A. Kim, Rebecca Zeng, John B Miller, Yifan Lu, and Ying Zhu
- Subjects
Adult ,Male ,medicine.medical_specialty ,genetic structures ,Visual Acuity ,Retinal Neovascularization ,Neovascularization ,03 medical and health sciences ,0302 clinical medicine ,Ophthalmology ,Intraretinal microvascular abnormalities ,Humans ,Medicine ,Prospective Studies ,Fluorescein Angiography ,Prospective cohort study ,Intraocular Pressure ,Aged ,030304 developmental biology ,0303 health sciences ,Diabetic Retinopathy ,medicine.diagnostic_test ,business.industry ,Retinal Vessels ,Optical coherence tomography angiography ,Diabetic retinopathy ,Middle Aged ,medicine.disease ,Fluorescein angiography ,eye diseases ,Diabetes Mellitus, Type 1 ,medicine.anatomical_structure ,Diabetes Mellitus, Type 2 ,030221 ophthalmology & optometry ,Female ,sense organs ,Tomography ,medicine.symptom ,business ,Tomography, Optical Coherence ,Optic disc - Abstract
To compare different scan protocols of wide-field swept-source optical coherence tomography angiography (SS-OCTA) for the detection of diabetic retinopathy (DR) lesions.Comparison of diagnostic approaches.A prospective, observational study was conducted at Massachusetts Eye and Ear from December 2018 to July 2019. Proliferative diabetic retinopathy (PDR), nonproliferative diabetic retinopathy (NPDR), and diabetic patients without DR were included. All patients were imaged using SS-OCTA using the following scan protocol: 3- × 3-mm Angio centered on the fovea; 6- × 6-mm Angio centered on the fovea and the optic disc; 15- × 9-mm Montage; and 12- × 12-mm Angio centered on the fovea and the optic disc. Images were independently evaluated by 2 graders for the presence or absence of DR lesions including microaneurysms, intraretinal microvascular abnormalities, neovascularization, nonperfusion areas, venous looping, and hard exudates. All statistical analyses were performed using commercial software.A total of 176 eyes in 119 participants were included in the study. The detection rate of neovascularization on 6- × 6-mm Angio centered on the fovea was approximately one-half that on 15- × 9-mm Montage (P.05) imaging. Combining 6- × 6-mm Angio imaging centered on the fovea and the optic disc could increase the rate to approximately two-thirds (P.05). The 12- × 12-mm Angio imaging centered on the combination of fovea and optic disc had detection rates comparable to those of 15- × 9-mm Montage imaging for all DR lesions (P.05). For microaneurysms, 6- × 6-mm Angio had better performance than 15- × 9-mm Montage (P.05).Wide-field SS-OCTA images were useful in detecting DR lesions. The 12- × 12-mm Angio imaging centered on the fovea and on the optic disc may be an optimal balance between speed and efficacy for evaluation of DR in clinical practice.
- Published
- 2020
31. Ultra‐widefield autofluorescence imaging findings in retinoschisis, rhegmatogenous retinal detachment and combined retinoschisis retinal detachment
- Author
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Panagiotis Salvanos, Demetrios G. Vavvas, Jesintha Navaratnam, and Ragnheiður Bragadóttir
- Subjects
Adult ,Male ,medicine.medical_specialty ,Fundus Oculi ,Retinoschisis ,Visual Acuity ,Fundus (eye) ,Retina ,Posterior margin ,Ophthalmology ,medicine ,Humans ,Fluorescein Angiography ,Aged ,Retrospective Studies ,business.industry ,Retinal Detachment ,Retinal detachment ,General Medicine ,Area of interest ,Middle Aged ,medicine.disease ,Fundus autofluorescence ,Scleral Buckling ,Autofluorescence ,Female ,Subretinal fluid ,business ,Tomography, Optical Coherence ,Follow-Up Studies - Abstract
Purpose Retinoschisis (RS), rhegmatogenous retinal detachment (RRD) and combined RS retinal detachment (RSRD) may resemble clinically and pose a diagnostic challenge. This study investigates the role of the fundus autofluorescence (AF) in differentiating RS, RRD and RSRD. Methods Fundus AF changes of 34 eyes diagnosed with RRD, 30 eyes with RS and 12 eyes with RSRD were retrospectively analysed. Ultra-widefield AF (UW-AF) image intensities obtained with the Optomap 200Tx were interpreted as hypo-, hyper- and isoautofluorescent or a mixed pattern with hypo- and hyperautofluorescence over and at the posterior margin (PM) of RRD, RS and RSRD. Results All RS eyes revealed isoautofluorescence over the area of RS, and nine eyes (30%) showed hypoautofluorescent PM. Among RRD, acute (≤2 weeks) and chronic (>2 weeks) RRD demonstrated distinct AF characteristics. Sixty-two per cent of RRD eyes had acute RRD. From those, 16 eyes (76%) demonstrated hypoautofluorescence over the detached area and 19 (90%) eyes with hyperautofluorescent PM. Sixty-two per cent of chronic RRD eyes demonstrated isoautofluorecence over the detached area. Eight RSRD eyes (67%) revealed hyperautofluorescence in the detached area. The positive predictive value (PPV) for hypoautofluorescence over the area of subretinal fluid (SRF) in RRD was 95%. The PPV for hyperautofluorescence over the area of SRF in RSRD was 100% and for isoautofluorescence for schitic area in RSRD and RS was 76%. Conclusion The UW-AF can be a useful non-invasive adjuvant tool to distinguish between RRD, RS and RSRD. Hypo- or hyperautofluorescence over the area of interest and hyperautofluorescent PM indicates the presence of SRF.
- Published
- 2020
32. Retinal Microvasculature Changes After Repair of Macula-off Retinal Detachment Assessed with Optical Coherence Tomography Angiography
- Author
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Dean Eliott, Thanos D. Papakostas, John B Miller, David M. Wu, Rebecca F Silverman, Leo A. Kim, Filippos Vingopoulos, K. Matthew McKay, Jay C Wang, Demetrios G. Vavvas, Anna Marmalidou, and Inês Laíns
- Subjects
medicine.medical_specialty ,Plexus ,Visual acuity ,Capillary plexus ,genetic structures ,business.industry ,Retinal detachment ,Retinal ,Optical coherence tomography angiography ,Foveal avascular zone ,medicine.disease ,eye diseases ,03 medical and health sciences ,Ophthalmology ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry ,Retinal capillary ,030221 ophthalmology & optometry ,medicine ,sense organs ,medicine.symptom ,business ,030217 neurology & neurosurgery - Abstract
Objective To characterize the microvascular retinal changes after repair of macula-off rhegmatogenous retinal detachment (RRD) using optical coherence tomography angiography (OCT-A). Patients and methods A retrospective review of patients who underwent repair of macula-off RRD. Fellow unaffected eyes were used as controls. Post-operative OCT-A allowed comparison of vessel density (VD) and foveal avascular zone (FAZ) area in the superficial and deep retinal capillary plexus (DCP) as well as VD in the choriocapillaris layer. Results Seventeen eyes of 17 RRD patients were included in the final analysis. There was a reduction in VD of the deep retinal capillary plexus in affected eyes compared to fellow eyes (p = 0.046). RRD eyes with reduced VD in DCP compared with their fellow control eyes had worse visual acuity after repair compared to those without (p = 0.032). No significant microvasculature changes were detected in the FAZ area and VD in the superficial capillary plexus and choriocapillaris compared to fellow eyes. Conclusion In macula-off RRD eyes, significant microvascular changes were detected in the DCP using OCT-A even after successful anatomical repair. Decreased VD in the DCP compared to the fellow healthy eyes was correlated with worse visual acuity.
- Published
- 2020
33. Short- and Long-Term Visual Outcomes in Patients Receiving Intravitreal Injections: The Impact of the Coronavirus 2019 Disease (COVID-19)-Related Lockdown
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Vivian Paraskevi Douglas, Konstantinos A. A. Douglas, Demetrios G. Vavvas, Joan W. Miller, and John B. Miller
- Subjects
genetic structures ,delay in care ,anti-VEGF ,nonadherence ,nonpersistence ,noncompliance ,treatment discontinuation ,pandemic ,General Medicine ,eye diseases - Abstract
Purpose: To investigate the short- and long-term impact of COVID-19—related lockdown on the vision of patients requiring intravitreal injections (IVI) for neovascular Age-related Macular degeneration (nvAMD), diabetic retinopathy (DR), central retinal vein occlusion (CRVO), or branch retinal vein occlusion (BRVO). Methods: This is a retrospective study from the Retina department of three Mass Eye and Ear centers. Charts of patients age of ≥ 18 years with any of the abovementioned diagnoses who had a scheduled appointment anytime between 17 March 2020 until 18 May 2020 (lockdown period in Boston, Massachusetts) were reviewed at baseline (up to 12 weeks before the lockdown), at first available follow-up (=actual f/u) during or after the lockdown period, at 3 months, 6 months, and at last available completed appointment of 2020. Results: A total of 1001 patients met the inclusion criteria. Of those patients, 479 (47.9%) completed their intended f/u appointment, while 522 missed it (canceled and “no show”). The delay in care of those who missed it was 59.15 days [standard deviation (SD) ± 49.6]. In these patients, significant loss of vision was noted at actual f/u [Best corrected visual acuity (BCVA) in LogMAR (Logarithm of the Minimum Angle of Resolution)—mean (±SD)—completed: 0.45 (±0.46), missed: 0.53 (±0.55); p = 0.01], which was more prominent in the DR group [Visual acuity (VA) change in LogMAR—mean (±SD); completed: 0.04 (±0.28), missed: 0.18 (±0.44); p = 0.02] and CRVO [completed: −0.06 (±0.27), missed: 0.11 (±0.35); p =
- Published
- 2022
34. Systemic Complement Activation Profiles in Nonexudative Age-Related Macular Degeneration: A Meta-Analysis
- Author
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Jonathan B. Lin, Stylianos Serghiou, Joan W. Miller, and Demetrios G. Vavvas
- Subjects
genetic structures ,complement ,age-related macular degeneration ,meta-analysis ,geographic atrophy ,General Medicine ,sense organs ,eye diseases - Abstract
Although complement inhibition has emerged as a possible therapeutic strategy for age-related macular degeneration (AMD), there is not a clear consensus regarding what aspects of the complement pathway are dysregulated in AMD and when this occurs relative to disease stage. We recently published a systematic review describing systemic complement activation profiles in patients with early/intermediate AMD or geographic atrophy (GA) compared to non-AMD controls. Here, we sought to meta-analyze these results to estimate the magnitude of complement dysregulation in AMD using restricted maximum likelihood estimation. The seven meta-analyzed studies included 710 independent participants with 23 effect sizes. Compared with non-AMD controls, patients with early/intermediate nonexudative AMD (N = 246) had significantly higher systemic complement activation, as quantified by the levels of complement proteins generated by common final pathway activation, and significantly lower systemic complement inhibition. In contrast, there were no statistically significant differences in the systemic levels of complement common final pathway activation products or complement inhibition in patients with GA (N = 178) versus non-AMD controls. We provide evidence that systemic complement over-activation is a feature of early/intermediate nonexudative AMD; no such evidence was identified for patients with GA. These findings provide mechanistic insights and inform future clinical trials.
- Published
- 2022
35. Spontaneous Closure and Recurrent Opening Times Two of a Macular Hole in a Surgically Naïve Eye
- Author
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Marisa G. Tieger, Leo A. Kim, and Demetrios G. Vavvas
- Subjects
Ophthalmology ,General Medicine - Published
- 2022
36. Novel Epigenetic Clock Biomarkers of Age-Related Macular Degeneration
- Author
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Saurav Mallik, Fran Grodstein, David A. Bennett, Demetrios G. Vavvas, and Bernardo Lemos
- Subjects
General Medicine - Abstract
Age-Related Macular Degeneration (AMD) is a bilateral ocular condition resulting in irreversible vision impairment caused by the progressive loss of photoreceptors in the macula, a region at the center of the retina. The progressive loss of photoreceptor is a key feature of dry AMD but not always wet AMD, though both forms of AMD can lead to loss of vision. Regression-based biological age clocks are one of the most promising biomarkers of aging but have not yet been used in AMD. Here we conducted analyses to identify regression-based biological age clocks for the retina and explored their use in AMD using transcriptomic data consisting of a total of 453 retina samples including 105 Minnesota Grading System (MGS) level 1 samples, 175 MGS level 2, 112 MGS level 3 and 61 MGS level 4 samples, as well as 167 fibroblast samples. The clocks yielded good separation among AMD samples with increasing severity score viz., MGS1-4, regardless of whether clocks were trained in retina tissue, dermal fibroblasts, or in combined datasets. Clock application to cultured fibroblasts, embryonic stem cells, and induced Pluripotent Stem Cells (iPSCs) were consistent with age reprograming in iPSCs. Moreover, clock application to in vitro neuronal differentiation suggests broader applications. Interesting, many of the age clock genes identified include known targets mechanistically linked to AMD and aging, such as GDF11, C16ORF72, and FBN2. This study provides new observations for retina age clocks and suggests new applications for monitoring in vitro neuronal differentiation. These clocks could provide useful markers for AMD monitoring and possible intervention, as well as potential targets for in vitro screens.
- Published
- 2022
37. Plasma Metabolomic Profiles Associated with Three-Year Progression of Age-Related Macular Degeneration
- Author
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Ines Lains, Kevin Mendez, Archana Nigalye, Raviv Katz, Vivian Paraskevi Douglas, Rachel S. Kelly, Ivana K. Kim, John B. Miller, Demetrios G. Vavvas, Liming Liang, Jessica Lasky-Su, Joan W. Miller, and Deeba Husain
- Subjects
genetic structures ,age-related macular degeneration ,dark adaptation ,metabolomics ,plasma ,Endocrinology, Diabetes and Metabolism ,Biochemistry ,Microbiology ,QR1-502 ,Article ,eye diseases ,sense organs ,Molecular Biology - Abstract
Plasma metabolomic profiles have been shown to be associated with age-related macular degeneration (AMD) and its severity stages. However, all studies performed to date have been cross-sectional and have not assessed progression of AMD. This prospective, longitudinal, pilot study analyzes, for the first time, the association between plasma metabolomic profiles and progression of AMD over a 3-year period. At baseline and 3 years later, subjects with AMD (n = 108 eyes) and controls (n = 45 eyes) were imaged with color fundus photos for AMD staging and tested for retinal function with dark adaptation (DA). Fasting plasma samples were also collected for metabolomic profiling. AMD progression was considered present if AMD stage at 3 years was more advanced than at baseline (n = 26 eyes, 17%). Results showed that, of the metabolites measured at baseline, eight were associated with 3-year AMD progression (p < 0.01) and 19 (p < 0.01) with changes in DA. Additionally, changes in the levels (i.e., between 3 years and baseline) of 6 and 17 metabolites demonstrated significant associations (p < 0.01) with AMD progression and DA, respectively. In conclusion, plasma metabolomic profiles are associated with clinical and functional progression of AMD at 3 years. These findings contribute to our understanding of mechanisms of AMD progression and the identification of potential therapeutics for this blinding disease.
- Published
- 2022
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38. Retinopathy Associated with Blood Disorders
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Grayson W. Armstrong, Saghar Bagheri, and Demetrios G. Vavvas
- Subjects
medicine.medical_specialty ,Blood Disorder ,business.industry ,Ophthalmology ,medicine ,medicine.disease ,business ,Retinopathy - Published
- 2022
39. Hyperspectral Imaging of the Retina: A Review
- Author
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John B Miller, Demetrios G. Vavvas, and Edith R Reshef
- Subjects
Diagnostic Imaging ,Retina ,business.industry ,Spectrum Analysis ,Hyperspectral imaging ,Image processing ,Ophthalmology ,medicine.anatomical_structure ,Retinal Diseases ,Image Processing, Computer-Assisted ,medicine ,Humans ,Computer vision ,Artificial intelligence ,business - Published
- 2019
40. CSF1R inhibition by small molecule affects T-helper cell differentiation independently of microglia depletion
- Author
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Fengyang Lei, Naiwen Cui, Chengxin Zhou, James Chodosh, Demetrios G. Vavvas, and Eleftherios I. Paschalis
- Abstract
Colony-stimulating factor 1 receptor (CSF1R) inhibition has been proposed as a specific method for microglia depletion. However, recent work revealed that in addition to microglia, CSF1R inhibition also affects other innate immune cells, such as peripheral monocytes and tissueresident macrophages of the lung, liver, spleen, and peritoneum. Here, we show that this effect is not restricted to innate immune cells only, but extends to the adaptive immune compartment. CSF1R inhibition alters the transcriptional profile of bone marrow cells that control T helper cell activation. In vivo or ex vivo inhibition of CSF1R profoundly changes the transcriptional profile of CD4+ cells and suppresses Th1 and Th2 differentiation in directionally stimulated and unstimulated cells and independently of microglia depletion. Given that T cells also contribute in CNS pathology, these effects may have practical implications in the interpretation of relevant experimental data.Significance statementHere we show that CSF1R inhibition affects not only innate immune cells and microglia, but also the adaptive immune compartment by suppressing Th1/Th2 differentiation of CD4+ cells, independently of microglia depletion.
- Published
- 2021
41. Aflibercept for Retinopathy of Prematurity: A Systematic Review and Meta-Analysis
- Author
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Po-Yu (Jay) Chen, Elizabeth J. Rossin, and Demetrios G. Vavvas
- Subjects
Vascular Endothelial Growth Factor A ,Receptors, Vascular Endothelial Growth Factor ,Recombinant Fusion Proteins ,Infant, Newborn ,Humans ,Infant ,Angiogenesis Inhibitors ,Retinopathy of Prematurity - Abstract
BACKGROUND AND OBJECTIVE: To determine the effectiveness of aflibercept in retinopathy of prematurity (ROP). PATIENTS AND METHODS: We performed a systematic review and meta-analysis of proportions from the literature in PubMed and Cochrane Library using search terms related to the use of aflibercept in ROP. Studies in non-preterm infants or that did not use aflibercept as the initial treatment were excluded. Risk of bias was assessed by the ROBINS-I (Risk Of Bias in Non-randomized Studies of Interventions) tool. RESULTS: We identified six case series. Collectively, 218 eyes were treated with aflibercept for ROP. We found an average 97% (95% confidence interval [CI], 93% to 99%) regression rate with aflibercept and an average 16% (95% CI, 5% to 41%) recurrence rate. With the exception of one outlier study, these numbers are similar to previous reports using anti–vascular endothelial growth factor (VEGF) agents in ROP. CONCLUSIONS: Aflibercept holds promise for use in ROP and has been demonstrated to be efficacious in six case series. Randomized, controlled clinical trials appear warranted to compare aflibercept with other anti-VEGF agents. [ Ophthalmic Surg Lasers Imaging. 2021;52:673–681.]
- Published
- 2021
42. UVA induces retinal photoreceptor cell death via receptor interacting protein 3 kinase mediated necroptosis
- Author
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Zhen Yu, Victor S. M. C. Correa, Nikolaos E. Efstathiou, Henar Albertos-Arranz, Xiaohong Chen, Kenji Ishihara, Yasuhiro Iesato, Toshio Narimatsu, Dimitrios Ntentakis, Demetrios G. Vavvas, Universidad de Alicante. Departamento de Fisiología, Genética y Microbiología, and Neurobiología del Sistema Visual y Terapia de Enfermedades Neurodegenerativas (NEUROVIS)
- Subjects
Cell death ,Cancer Research ,Cellular and Molecular Neuroscience ,UVA ,Immunology ,Receptor interacting protein ,Necroptosis ,Retinal photoreceptor ,Cell Biology ,3 kinase - Abstract
Ultraviolet light A (UVA) is the only UV light that reaches the retina and can cause indirect damage to DNA via absorption of photons by non-DNA chromophores. Previous studies demonstrate that UVA generates reactive oxygen species (ROS) and leads to programmed cell death. Programmed cell death (PCD) has been implicated in numerous ophthalmologic diseases. Here, we investigated receptor interacting protein 1 and 3 (RIPK1 and RIPK3) kinases, key signaling molecules of PCD, in UVA-induced photoreceptor injury using in vitro and ex vivo models. UVA irradiation activated RIPK3 but not RIPK1 and mediated necroptosis through MLKL that lie downstream of RIPK3 and induced apoptosis through increased oxidative stress. Moreover, RIPK3 but not RIPK1 inhibition suppresses UVA-induced cell death along with the downregulation of MLKL and attenuates the levels of oxidative stress and DNA fragmentation. In conclusion, these results identify RIPK3, not RIPK1, as a critical regulator of UVA-induced necroptosis cell death in photoreceptors and highlight RIPK3 potential as a neuroprotective target. This work was supported by the Yeatts Family Foundation (D.G.V.); Monte J. Wallace (D.G.V.); 2013 Macula Society Research Grant Award (to D.G.V.); a Physician Scientist Award (to D.G.V.); unrestricted grant from the Research to Prevent Blindness Foundation (to J.W.M. and D.G.V.); National Eye Institute (NEI) R21EY023079-01/A1 (to D.G.V.); NEI Grant EY014104 (Massachusetts Eye and Ear Infirmary Core Grant) (to D.G.V.); Loeffler Family Fund (D.G.V.); R01EY025362-01 (to D.G.V.); ARI Young Investigator Award (to D.G.V.); Foundation Lions Eye Research Fund (D.G.V.); NIH NEI Core Grant P30EY003790 (to D.G.V.); Loeffler Family Fund (to D.G.V.); ARI Young Investigator Award (to D.G.V.). Shenzhen Science and Technology Program (Grant No. JCYJ20220530153607015); Shenzhen Science and Technology Program (Grant No. JCYJ20220531094004010); Shenzhen-Hong Kong Co-financing Project (Grant No. SGDX20190920110403741); Guangdong Basic and Applied Basic Research Foundation (No. 2022A1515012326); Shenzhen Science and Technology Program (Grant No. JSGG20201102174200001); Shenzhen Key Medical Discipline Construction Fund (No. SZXK038); Sanming Project of Medicine in Shenzhen (No. SZSM202011015); Shenzhen Fund for Guangdong Provincial High level Clinical Key Specialties (No. SZGSP014); National Natural Science Foundation of China (No. 82271103).
- Published
- 2021
43. Receptor interacting protein 3 kinase, not 1 kinase, through MLKL-mediated necroptosis is involved in UVA-induced corneal endothelium cell death
- Author
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Yanyun Chen, Victor S M C Correa, Zhen Yu, Demetrios G. Vavvas, Xiaohong Chen, Toshio Narimatsu, Kenji Ishihara, Yasuhiro Iesato, Dimitrios Ntentakis, and Nikolaos Efstathiou
- Subjects
Cancer Research ,Programmed cell death ,Corneal endothelium ,QH573-671 ,Chemistry ,Kinase ,Necroptosis ,Immunology ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Cell Biology ,Article ,Cell biology ,Cellular and Molecular Neuroscience ,RIPK1 ,Downregulation and upregulation ,TRIF ,Cell death and immune response ,sense organs ,Cytology ,Eye diseases ,RC254-282 ,Ex vivo - Abstract
Ultraviolet (UV) is one of the most energetic radiations in the solar spectrum that can result in various tissue injury disorders. Previous studies demonstrated that UVA, which represents 95% of incident photovoltaic radiation, induces corneal endothelial cells (CECs) death. Programmed cell death (PCD) has been implicated in numerous ophthalmologic diseases. Here, we investigated receptor-interacting protein 3 kinase (RIPK3), a key signaling molecule of PCD, in UVA-induced injury using a short-term corneal endothelium (CE) culture model. UVA irradiation activated RIPK3 and mediated necroptosis both in mouse CE and primary human CECs (pHCECs). UVA irradiation was associated with upregulation of key necroptotic molecules (DAI, TRIF, and MLKL) that lie downstream of RIPK3. Moreover, RIPK3 inhibition or silencing in primary corneal endothelial cells suppresses UVA-induced cell death, along with downregulation of MLKL in pHCECs. In addition, genetic inhibition or knockout of RIPK3 in mice (RIPK3K51A and RIPK3−/− mice) similarly attenuates cell death and the levels of necroptosis in ex vivo UVA irradiation experiments. In conclusion, these results identify RIPK3, not RIPK1, as a critical regulator of UVA-induced cell death in CE and indicate its potential as a future protective target.
- Published
- 2021
44. Retrospective Analysis of Retinal Imaging in COVID-19 Positive Patients at a Tertiary Eye Care Center
- Author
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Jade Y Moon, Lucia Sobrin, Raviv Katz, John B Miller, Demetrios G. Vavvas, Neal S Patel, and Karen M Wai
- Subjects
retina ,medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,genetic structures ,Eye care ,chemistry.chemical_compound ,Ophthalmology ,Edema ,medicine ,fundus photography ,Original Research ,Retina ,optical coherence tomography ,medicine.diagnostic_test ,SARS-CoV-2 ,business.industry ,Fundus photography ,COVID-19 ,Retinal ,Clinical Ophthalmology ,eye diseases ,Cotton wool spots ,medicine.anatomical_structure ,chemistry ,Retinal imaging ,sense organs ,medicine.symptom ,business - Abstract
Neal S Patel,1,* Jade Y Moon,1,* Raviv Katz,1 Karen M Wai,1 Lucia Sobrin,2 Demetrios G Vavvas,2 John B Miller1,2 1Harvard Retinal Imaging Lab, Mass Eye and Ear, Boston, MA, USA; 2Retina Service, Mass Eye and Ear, Boston, MA, USA*These authors contributed equally to this workCorrespondence: John B MillerRetina Service, Mass Eye and Ear, Department of Ophthalmology, Harvard Medical School, Harvard Retinal Imaging Lab, 243 Charles St, Boston, MA, 02114, USATel +617 573-3750Fax +617 573-3698Email john_miller@meei.harvard.eduPurpose: Since the start of the COVID-19 pandemic, numerous authors have published data demonstrating retinal changes found in patients with COVID-19. However, others have debated the significance of these findings and the effects of COVID-19 on the retina remain uncertain. This study aims to better understand retinal findings in patients with COVID-19.Patients and Methods: A retrospective review of patients with a history of a positive COVID-19 polymerase chain reaction test was performed between March 1st, 2020 and October 31st, 2020. Patients were included if they presented within 90 days of their first positive COVID-19 test and underwent color fundus photography and/or OCT of the macula. All images were reviewed by two independent graders who assessed the presence of retinal heme, cotton wool spots, vascular sheathing, and disc edema, as well as hyper-reflective changes, intra-retinal fluid, and sub-retinal fluid on OCT.Results: A total of 119 eyes from 61 patients were included. Among 83 eyes which underwent OCT of the macula, inner retinal hyper-reflective changes were seen in 16.9% (n=14), outer retinal hyper-reflective changes in 18.1% (n=15), intra-retinal fluid in 28.9% (n=24), and sub-retinal fluid in 14.5% (n=12). Among 48 eyes which underwent color fundus photography, retinal hemorrhage was seen in 27.1% (n=13), optic disc edema in 2.1% (n=1), and cotton wool spots in none of the eyes. Sub-analysis of 70 eyes from 41 patients with no alternative retinal pathology to potentially explain the above findings revealed none of the above exam findings on OCT of the macula (n=35), fundus photography (n=28), or documented exam (n=66).Conclusion: While a number of patients seen after COVID-19 infection demonstrated retinal findings, all could be explained by pre-existing retinal conditions. In a sub-group of eyes without pre-existing retinal disease, we did not identify any retinal findings that could be associated with COVID-19.Keywords: COVID-19, SARS-CoV-2, retina, optical coherence tomography, fundus photography
- Published
- 2021
45. Pathogenic mitochondrial dysfunction and metabolic abnormalities
- Author
-
Konstantina Sampani, Mark Pernokas, Anastasios N. Mavrakis, Krishna Kodukula, Carl A. Pinkert, David N. Harpp, Ioannis P. Glavas, Iphigenia Kanara, Kosta Steliou, Douglas V. Faller, Walter H. Moos, Constantin Tamvakopoulos, Demetrios G. Vavvas, Natalia Kamperi, Whitney R. Powers, Julie Pernokas, and Robert J. Zamboni
- Subjects
Mitochondrial Diseases ,Cell ,Disease ,Mitochondrion ,medicine.disease_cause ,Biochemistry ,Pathogenesis ,Metabolic Diseases ,medicine ,Animals ,Humans ,Coronavirus ,Pharmacology ,Genetics ,ATP synthase ,biology ,COVID-19 ,Neurodegenerative Diseases ,Phenotype ,Mitochondria ,Metabolic pathway ,Oxidative Stress ,medicine.anatomical_structure ,biology.protein ,Diet, Healthy ,Energy Metabolism - Abstract
Herein we trace links between biochemical pathways, pathogenesis, and metabolic diseases to set the stage for new therapeutic advances. Cellular and acellular microorganisms including bacteria and viruses are primary pathogenic drivers that cause disease. Missing from this statement are subcellular compartments, importantly mitochondria, which can be pathogenic by themselves, also serving as key metabolic disease intermediaries. The breakdown of food molecules provides chemical energy to power cellular processes, with mitochondria as powerhouses and ATP as the principal energy carrying molecule. Most animal cell ATP is produced by mitochondrial synthase; its central role in metabolism has been known for >80 years. Metabolic disorders involving many organ systems are prevalent in all age groups. Progressive pathogenic mitochondrial dysfunction is a hallmark of genetic mitochondrial diseases, the most common phenotypic expression of inherited metabolic disorders. Confluent genetic, metabolic, and mitochondrial axes surface in diabetes, heart failure, neurodegenerative disease, and even in the ongoing coronavirus pandemic.
- Published
- 2021
46. Open Globe Injury with Intraocular Foreign Body
- Author
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Seanna Grob, John B Miller, Dean Eliott, Chloe Yang Ling Li, Yvonne Wang, Leo A. Kim, Filippos Vingopoulos, and Demetrios G. Vavvas
- Subjects
Intraocular foreign body ,Open globe ,business.industry ,Ocular trauma ,medicine.disease ,Article ,03 medical and health sciences ,0302 clinical medicine ,Open Globe Injury ,030221 ophthalmology & optometry ,Medicine ,Optometry ,Foreign body ,business ,030217 neurology & neurosurgery - Abstract
PURPOSE: To investigate characteristics of Open Globe Injuries (OGI) that presented with Intra-Ocular Foreign Body (IOFB), along with their long-term visual outcomes, complications and need for subsequent surgeries. METHODS: Retrospective interventional consecutive case series of OGIs with IOFBs that presented to the Eye Trauma service at the Massachusetts Eye and Ear from 2010 to 2015. Data collected included time from injury to OGI repair, location of injury and IOFB, retinal detachment (RD) rate, presenting and final visual acuity (VA) and subsequent surgeries. RESULTS: Fifty-seven consecutive cases of OGIs with IOFBs were included. The majority of patients were male (93%), mean age was 37 years and mean follow-up was 28 +/− 22 months. The median time from injury to OGI repair was 0 days (range: 0–16 days). Overall, 38/57 (66.7%) eyes achieved final vision of 20/40 or better and 43/57 (75.4%) vision of 20/150 or better. Zone I injuries were the most common (86%), followed by Zone II (16%), and Zone III (10%). 33 cases had IOFBs in the anterior segment only and 24 cases had posterior segment involvement. In total, 30% of cases (17/57) were complicated by an RD, 58.3% (14/24) in the posterior versus 9.1% (3/33) in the anterior IOFB group.( p
- Published
- 2021
47. Dyslipidemia in age-related macular degeneration
- Author
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Jonathan B. Lin, Omar A. Halawa, Deeba Husain, Joan W. Miller, and Demetrios G. Vavvas
- Subjects
Ophthalmology ,Macular Degeneration ,Humans ,Metabolomics ,Review Article ,Lipid Metabolism ,Lipids ,Aged ,Dyslipidemias - Abstract
Lipid-rich drusen are the sine qua non of age-related macular degeneration (AMD), the leading cause of blindness in older adults in the developed world. Efforts directed at uncovering effective therapeutic strategies have led to the hypothesis that altered lipid metabolism may play a pathogenic role in AMD. This hypothesis is supported by the fact that: (1) drusen, the hallmark histopathologic feature of AMD, are composed of lipids, (2) polymorphisms of genes involved in lipid homeostasis are associated with increased odds of AMD, (3) metabolomics studies show that patients with AMD have alterations in metabolites from lipid pathways, and (4) alterations in serum lipid profiles as a reflection of systemic dyslipidemia are associated with AMD. There is strong evidence that statins, which are well described for treating dyslipidemia and reducing risk associated with cardiovascular disease, may have a role for treating certain cohorts of AMD patients, but this has yet to be conclusively proven. Of interest, the specific changes in serum lipoprotein profiles associated with decreased cardiovascular risk (i.e., high HDL levels) have been shown in some studies to be associated with increased risk of AMD. In this review, we highlight the evidence that supports a role for altered lipid metabolism in AMD and provide our perspective regarding the remaining questions that need to be addressed before lipid-based therapies can emerge for specific cohorts of AMD patients.摘要: 富含脂质的玻璃疣是年龄相关性黄斑变性 (AMD) 的重要特征, AMD是发达国家老年人失明的主要原因。为发现有效的治疗策略提出了一个假说, 即脂质代谢的改变可能在AMD中起致病作用。这一假说目前有以下事实支持: (1) 作为AMD标志性组织病理学特征的玻璃疣是由脂质组成, (2) 参与脂质稳态的基因多态性与AMD的患病几率增加有关, (3) 代谢组学研究表明AMD患者的脂质代谢产物发生了改变, 以及4) 反映全身性血脂异常的血脂谱变化与AMD有关。有强有力的证据表明, 他汀类药物可能在治疗某些AMD患者的队列中发挥作用, 但这一观点尚未得到确凿的证明, 且他汀类药物在治疗血脂异常和降低与心血管疾病相关的风险方面得到了证实。有趣的是, 一些研究表明, 血清脂蛋白谱中与心血管风险降低 (即高密度脂蛋白水平) 相关的特定变化与AMD风险增加有关。在这篇综述中, 我们强调了支持脂质代谢改变在AMD中作用的证据, 并就AMD患者特定队列中在脂质治疗前需要解决的问题提出了我们的观点。.
- Published
- 2021
48. Opposing roles of blood-borne monocytes and tissue-resident macrophages in limbal stem cell damage after ocular injury
- Author
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Fengyang Lei, Demetrios G. Vavvas, Eleftherios I. Paschalis, Mirja Mittermaier, Claes H. Dohlman, Reza Dana, Bruce R. Ksander, James Chodosh, and Chengxin Zhou
- Subjects
business.industry ,Cell ,Proinflammatory cytokine ,Immune system ,medicine.anatomical_structure ,Downregulation and upregulation ,Apoptosis ,Cancer research ,Medicine ,Tumor necrosis factor alpha ,Limbal stem cell ,sense organs ,business ,Chemical Injury - Abstract
Limbal stem cell (LSC) deficiency is a frequent and severe complication after chemical injury to the eye. Previous studies have assumed that this is mediated directly by the caustic agent. Here we show that LSC damage occurs through immune cell mediators, even without direct injury to LSCs. In particular, pH elevation in the anterior chamber (AC) causes acute uveal stress, release of inflammatory cytokines at the basal limbal tissue, and subsequent LSC loss. Peripheral CCR2+ CX3CR1- monocytes are the key mediators of LSC damage, through the upregulation of tumor necrosis factor alpha (TNF-α) at the limbus. In contrast to peripherally-derived monocytes, CX3CR1+ CCR2- tissue-resident macrophages have a protective role and their depletion prior to injury exacerbates LSC loss and increases LSC vulnerability to TNF-α-mediated apoptosis independently of CCR2+ cell infiltration into the tissue. Consistently, repopulation of the tissue by new resident macrophages not only restores the protective M2-like phenotype of macrophages but also suppresses LSC loss after exposure to inflammatory signals. These findings may have clinical implication in patient with chemical burns.SignificanceLimbal stem cell (LSC) loss after chemical burn is a significant clinical problem that has long been thought to be the result of direct chemical injury. This study demonstrates the existence of competing inflammatory mechanism responsible for LSC death, mediated by infiltrating peripheral monocytes that antagonize and overcome the protective role of tissue-resident macrophages. Thus, enhancing the role of tissue-resident macrophages while suppressing that of infiltrating monocytes could be a novel therapeutic strategy for LSC survival.
- Published
- 2021
49. Complement Inhibition for Geographic Atrophy: A Tempting Target with Mixed Results
- Author
-
Joan W. Miller, Demetrios G. Vavvas, Omar A Halawa, and Jonathan B Lin
- Subjects
0301 basic medicine ,Opinion ,retina ,genetic structures ,Context (language use) ,Drusen ,Bioinformatics ,Pathogenesis ,03 medical and health sciences ,0302 clinical medicine ,geographic atrophy ,medicine ,complement ,age-related macular degeneration ,business.industry ,drusen ,General Medicine ,Macular degeneration ,medicine.disease ,eye diseases ,Complement system ,Complement (complexity) ,030104 developmental biology ,Factor H ,030221 ophthalmology & optometry ,Medicine ,Gene polymorphism ,sense organs ,business - Abstract
Age-related macular degeneration (AMD) is a leading cause of blindness in older adults. One of the strongest genetic risk factors for AMD is a complement factor H (CFH) gene polymorphism characterized by a tyrosine-histidine change at amino acid position 402 (Y402H). The magnitude of this association between the Y402H variant and AMD is among the strongest that has been identified for any complex, multifactorial human disease. This strong association has motivated researchers to investigate a potential link between various elements of the complement pathway and AMD pathogenesis. Given the possible contribution of complement dysregulation to AMD, complement inhibition has emerged as a therapeutic strategy for slowing geographic atrophy (GA). Randomized clinical trials thus far have yielded mixed results. In this article, we provide the historical context for complement inhibition as a strategy for treating GA, discuss potential advantages and disadvantages of complement inhibition, and highlight the questions that must be addressed before complement inhibition can take center stage as a therapy for AMD.
- Published
- 2021
50. CSF1R inhibition by a small-molecule inhibitor is not microglia specific; affecting hematopoiesis and the function of macrophages
- Author
-
James Chodosh, Fengyang Lei, Eleftherios I. Paschalis, Chengxin Zhou, Demetrios G. Vavvas, and Naiwen Cui
- Subjects
education.field_of_study ,Multidisciplinary ,Myeloid ,Microglia ,Chemistry ,CD68 ,Phagocytosis ,Population ,microglia ,Spleen ,Biological Sciences ,CSF1R ,hematopoiesis ,Cell biology ,macrophages ,Haematopoiesis ,medicine.anatomical_structure ,Immune system ,Immunology and Inflammation ,medicine ,CNS ,education - Abstract
Colony-stimulating factor 1 receptor (CSF1R) inhibition has been proposed as a method for microglia depletion, with the assumption that it does not affect peripheral immune cells. Here, we show that CSF1R inhibition by PLX5622 indeed affects the myeloid and lymphoid compartments, causes long-term changes in bone marrow-derived macrophages by suppressing interleukin 1β, CD68, and phagocytosis but not CD208, following exposure to endotoxin, and also reduces the population of resident and interstitial macrophages of peritoneum, lung, and liver but not spleen. Thus, small-molecule CSF1R inhibition is not restricted to microglia, causing strong effects on circulating and tissue macrophages that perdure long after cessation of the treatment. Given that peripheral monocytes repopulate the central nervous system after CSF1R inhibition, these changes have practical implications for relevant experimental data.
- Published
- 2020
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