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Yin Y, Benowitz LI. In Vitro and In Vivo Methods for Studying Retinal Ganglion Cell Survival and Optic Nerve Regeneration. Methods Mol Biol 2018;1695:187-205.Abstract
Glaucoma is marked by a progressive degeneration of the optic nerve and delayed loss of retinal ganglion cells (RGCs), the projection neurons of the eye. Because RGCs are not replaced and because surviving RGCs cannot regenerate their axons, the visual loss in glaucoma is largely irreversible. Here, we describe methods to evaluate treatments that may be beneficial for treating glaucoma using in vitro cell culture models (immunopanning to isolate neonatal RGCs, dissociated mature retinal neurons, retinal explants) and in vivo models that test potential treatments or investigate underlying molecular mechanisms in an intact system. Potentially, use of these models can help investigators continue to improve treatments to preserve RGCs and restore visual function in patients with glaucoma.
Yin J, Kheirkhah A, Dohlman T, Saboo U, Dana R. Reduced Efficacy of Low-dose Topical Steroids in Dry Eye Disease Associated with Graft-versus-host Disease. Am J Ophthalmol 2018;Abstract
PURPOSE: To compare the response of dry eye disease (DED) to treatment with topical steroid in patients with and without graft-versus-host disease (GVHD). DESIGN: Post-hoc analysis of a double-masked, randomized clinical trial. METHODS: This single-center study included 42 patients with moderate to severe DED associated with (N=21) or without (N=21) chronic GVHD. In each group, patients received either loteprednol etabonate 0.5% ophthalmic suspension or artificial tears twice daily for 4 weeks. Clinical data, including Ocular Surface Disease Index (OSDI) questionnaire, corneal fluorescein staining (CFS), conjunctival lissamine green staining, tear break-up time (TBUT), and Schirmer's test, were evaluated before and after treatment. RESULTS: There were no significant differences in signs and symptoms of DED between the groups at baseline. In non-GVHD patients receiving loteprednol treatment, the average OSDI score decreased by 34% from 49.5 ± 5.9 to 32.6 ± 4.8 (Mean±SEM, P=0.001) and the average CFS score decreased by 41% from 5.6 ± 0.6 to 3.3 ± 0.9 (P=0.02). On the other hand, loteprednol treatment in GVHD patients resulted in minimal change in OSDI (59.2±6.7 to 61.1±7.1, 3% increase, P=0.66) and CFS (5.5±0.5 to 5.3±1.1, 4% decrease, P=0.85) scores. Treatment with artificial tears resulted in 22% decrease of OSDI (P=0.10) and 32% decrease of CFS (P=0.02) scores in non-GVHD patients, and had minimal effect in patients with GVHD. CONCLUSIONS: DED patient with ocular GVHD have a less favorable response to a low-dose topical steroid regimen compared with those without ocular GVHD even with similar baseline disease severity.
Yin J, Jurkunas U. Limbal Stem Cell Transplantation and Complications. Semin Ophthalmol 2017;:1-8.Abstract
Corneal epithelial stem cells are adult somatic stem cells located at the limbus and represent the ultimate source of transparent corneal epithelium. When these limbal stem cells become dysfunctional or deficient, limbal stem cell deficiency (LSCD) develops. LSCD is a major cause of corneal scarring and is particularly prevalent in chemical and thermal burns of the ocular surface. LSCD leads to conjunctivalization of the corneal surface, neovascularization, recurrent or persistent epithelial defects, ocular surface inflammation, and scarring that, in turn, lead to decreased vision, pain, and impaired quality of life. Several techniques have been reported for limbal stem cell transplantation (LSCT). We introduce the surgical techniques, examine the success rate, and discuss the postoperative complications of conjunctival limbal autograft (CLAU), cultivated limbal stem cell transplantation (CLET), simple limbal epithelial transplantation (SLET), and limbal allograft, including keratolimbal allografts (KLAL) and living-related conjunctival allograft (LR-CLAL).
Ying G-S, Vanderveen D, Daniel E, Quinn GE, Baumritter A, to of Group TAEA-PRPC. Risk Score for Predicting Treatment-Requiring Retinopathy of Prematurity (ROP) in the Telemedicine Approaches to Evaluating Acute-Phase ROP Study. Ophthalmology 2016;123(10):2176-82.Abstract

PURPOSE: To develop a risk score for predicting treatment-requiring retinopathy of prematurity (TR-ROP) in the Telemedicine Approaches to Evaluating Acute-Phase Retinopathy of Prematurity (e-ROP) study. DESIGN: Second analyses of an observational cohort study. PARTICIPANTS: Infants with birth weight (BW) <1251 g who had ≥1 imaging session by 34 weeks of postmenstrual age (PMA) and ≥1 subsequent retinopathy of prematurity (ROP) examination for determining TR-ROP by study-certified ophthalmologists. METHODS: Nonphysician trained readers evaluated wide-field retinal image sets for characteristics of ROP, pre-plus/plus disease, and retinal hemorrhage. Risk score points for predicting TR-ROP were derived from the regression coefficients of significant predictors in a multivariate logistic regression model. MAIN OUTCOME MEASURES: TR-ROP. RESULTS: Eighty-five of 771 infants (11.0%) developed TR-ROP. In a multivariate model, significant predictors for TR-ROP were gestational age (GA) (odds ratio [OR], 5.7; 95% confidence interval [CI], 1.7-18.9 for ≤25 vs. ≥28 weeks), need for respiratory support (OR, 7.0; 95% CI, 1.3-37.1 for high-frequency oscillatory ventilation vs. no respiratory support), slow weight gain (OR, 2.4; 95% CI, 1.2-4.6 for weight gain ≤12 g/day vs. >15 g/day), and image findings at the first image session including number of quadrants with pre-plus (OR, 3.8; 95% CI, 1.5-9.7 for 4 pre-plus quadrants vs. no pre-plus), stage and zone of ROP (OR, 4.7; 95% CI, 2.1-11.8 for stage 1-2 zone I, OR, 5.9; 95% CI, 2.1-16.6 for stage 3 zone I vs. no ROP), and presence of blot hemorrhage (OR, 3.1; 95% CI, 1.4-6.7). Image findings predicted TR-ROP better than GA (area under receiver operating characteristic curve [AUC] = 0.82 vs. 0.75, P = 0.03). The risk of TR-ROP steadily increased with higher risk score and predicted TR-ROP well (AUC = 0.88; 95% CI, 0.85-0.92). Risk score ≥3 points for predicting TR-ROP had a sensitivity of 98.8%, specificity of 40.1%, and positive and negative predictive values of 17.0% and 99.6%, respectively. CONCLUSIONS: Image characteristics at 34 PMA weeks or earlier independently predict TR-ROP. If externally validated in other infants, risk score, calculated from image findings, GA, weight gain, and respiratory support, enables early identification of infants in need of increased surveillance for TR-ROP.

Ying Y, Ueta T, Jiang S, Lin H, Wang Y, Vavvas D, Wen R, Chen Y-G, Luo Z. Metformin inhibits ALK1-mediated angiogenesis via activation of AMPK. Oncotarget 2017;8(20):32794-32806.Abstract
Anti-VEGF therapy has been proven to be effective in the treatment of pathological angiogenesis. However, therapy resistance often occurs, leading to development of alternative approaches. The present study examines if AMPK negatively regulates ALK1-mediated signaling events and associated angiogenesis. Thus, we treated human umbilical vein endothelial cells with metformin as well as other pharmacological AMPK activators and showed that activation of AMPK inhibited Smad1/5 phosphorylation and tube formation induced by BMP9. This event was mimicked by expression of the active mutant of AMPKα1 and prevented by the dominant negative AMPKα1. Metformin inhibition of BMP9 signaling is possibly mediated by upregulation of Smurf1, leading to degradation of ALK1. Furthermore, metformin suppressed BMP9-induced angiogenesis in mouse matrigel plug. In addition, laser photocoagulation was employed to evaluate the effect of metformin. The data revealed that metformin significantly reduced choroidal neovascularization to a level comparable to LDN212854, an ALK1 specific inhibitor. In conjunction, metformin diminished expression of ALK1 in endothelium of the lesion area. Collectively, our study for the first time demonstrates that AMPK inhibits ALK1 and associated angiogenesis/neovascularization. This may offer us a new avenue for the treatment of related diseases using clinically used pharmacological AMPK activators like metformin in combination with other strategies to enhance the treatment efficacy or in the case of anti-VEGF resistance.
Yonekawa Y, Kim IK, Gragoudas ES, Njauw C-NJ, Tsao H, Jakobiec FA, Stacy RC. Aggressive skull base metastasis from uveal melanoma: a clinicopathologic study. Eur J Ophthalmol 2014;24(5):811-3.Abstract

PURPOSE: We present the clinical, pathologic, and genetic findings of the first reported case of choroidal melanoma that developed a late recurrence and aggressive metastasis to the skull base without evidence of hepatic involvement. METHODS: Retrospective chart review and clinicopathologic correlation of ocular and brain tissue, including sequencing of BAP1 for mutations. RESULTS: A 55-year-old woman was diagnosed with choroidal melanoma and treated with proton radiotherapy. Six years later, she developed a rapidly growing local recurrence involving the ciliary body and iris. Upon enucleation, histopathology revealed an iris and ciliary body epithelioid melanoma that was contiguous with the previously treated, regressed spindle cell choroidal melanoma. Imaging was initially negative for brain involvement. Two months later, she developed cranial neuropathies and was found to have a large skull base lesion that required surgical debulking for pain palliation. Histopathology confirmed the lesion to be metastatic melanoma. Both ocular and brain tumor specimens were wild-type for BAP1. Throughout her course, she developed no hepatic metastases. CONCLUSIONS: Uveal melanoma may metastasize to the skull base. The present case was characterized by delayed onset and unusual aggressiveness of the metastatic disease, and lack of BAP1 mutation. The unusual course highlights a unique phenotype that may reflect an alternate molecular mechanism for metastatic disease.

Yonekawa Y, Wu W-C, Nitulescu CE, Chan PRV, Thanos A, Thomas BJ, Todorich B, Drenser KA, Trese MT, Capone A. PROGRESSIVE RETINAL DETACHMENT IN INFANTS WITH RETINOPATHY OF PREMATURITY TREATED WITH INTRAVITREAL BEVACIZUMAB OR RANIBIZUMAB. Retina 2017;Abstract
PURPOSE: Fibrovascular contraction and tractional retinal detachment (TRD) are recognized complications associated with the use of anti-vascular endothelial growth factor agents in vasoproliferative vitreoretinopathies. The authors characterize TRDs that developed after intravitreal bevacizumab or ranibizumab therapy for vascularly active retinopathy of prematurity. METHODS: This is an international, multicenter, interventional, retrospective, case series. Thirty-five eyes from 23 infants were included. Inclusion required anti-vascular endothelial growth factor treatment of Type 1 retinopathy of prematurity with progression to TRD. RESULTS: Mean gestational age was 26 ± 2 weeks, and mean birth weight was 873 ± 341 g. Mean postmenstrual age on the day of injection was 35 ± 2 weeks. Retinal detachment was noted a mean of 70 days (median, 34; range, 4-335) after injection. Eleven percent detached within 1 week, 23% within 2 weeks, and 49% within 4 weeks. The highest stage of retinopathy of prematurity noted was 4A in 29%, 4B in 37%, and 5 in 34% of eyes. Time to RD negatively correlated with postmenstrual age at the time of injection (Rho = -0.54; P < 0.01). Three TRD configurations were observed: 1) conventional peripheral elevated ridge or volcano-shaped Stage 5 detachment, 2) midperipheral detachment with tight circumferential vectors, and 3) very posterior detachment with prepapillary contraction. Full or partial reattachment was achieved with surgical intervention in 86% of eyes. CONCLUSION: Progressive atypical TRD may occur after anti-vascular endothelial growth factor injections for retinopathy of prematurity. The configuration of the detachment varies with the extent of primary retinal vascularization present at the time of treatment.
Yonekawa Y, Wu W-C, Kusaka S, Robinson J, Tsujioka D, Kang KB, Shapiro MJ, Padhi TR, Jain L, Sears JE, Kuriyan AE, Berrocal AM, Quiram PA, Gerber AE, Paul Chan RV, Jonas KE, Wong SC, Patel CK, Abbey AM, Spencer R, Blair MP, Chang EY, Papakostas TD, Vavvas DG, Sisk RA, Ferrone PJ, Henderson RH, Olsen KR, Hartnett EM, Chau FY, Mukai S, Murray TG, Thomas BJ, Meza AP, Drenser KA, Trese MT, Capone A. Immediate Sequential Bilateral Pediatric Vitreoretinal Surgery: An International Multicenter Study. Ophthalmology 2016;123(8):1802-8.Abstract

PURPOSE: To determine the feasibility and safety of bilateral simultaneous vitreoretinal surgery in pediatric patients. DESIGN: International, multicenter, interventional, retrospective case series. PARTICIPANTS: Patients 17 years of age or younger from 24 centers worldwide who underwent immediate sequential bilateral vitreoretinal surgery (ISBVS)-defined as vitrectomy, scleral buckle, or lensectomy using the vitreous cutter-performed in both eyes sequentially during the same anesthesia session. METHODS: Clinical history, surgical details and indications, time under anesthesia, and intraoperative and postoperative ophthalmic and systemic adverse events were reviewed. MAIN OUTCOME MEASURES: Ocular and systemic adverse events. RESULTS: A total of 344 surgeries from 172 ISBVS procedures in 167 patients were included in the study. The mean age of the cohort was 1.3±2.6 years. Nonexclusive indications for ISBVS were rapidly progressive disease (74.6%), systemic morbidity placing the child at high anesthesia risk (76.0%), and residence remote from surgery location (30.2%). The most common diagnoses were retinopathy of prematurity (ROP; 72.7% [P < 0.01]; stage 3, 4.8%; stage 4A, 44.4%; stage 4B, 22.4%; stage 5, 26.4%), familial exudative vitreoretinopathy (7.0%), abusive head trauma (4.1%), persistent fetal vasculature (3.5%), congenital cataract (1.7%), posterior capsular opacification (1.7%), rhegmatogenous retinal detachment (1.7%), congenital X-linked retinoschisis (1.2%), Norrie disease (2.3%), and viral retinitis (1.2%). Mean surgical time was 143±59 minutes for both eyes. Higher ROP stage correlated with longer surgical time (P = 0.02). There were no reported intraoperative ocular complications. During the immediate postoperative period, 2 eyes from different patients demonstrated unilateral vitreous hemorrhage (0.6%). No cases of endophthalmitis, choroidal hemorrhage, or hypotony occurred. Mean total anesthesia time was 203±87 minutes. There were no cases of anesthesia-related death, malignant hyperthermia, anaphylaxis, or cardiac event. There was 1 case of reintubation (0.6%) and 1 case of prolonged oxygen desaturation (0.6%). Mean follow-up after surgery was 103 weeks, and anatomic success and globe salvage rates were 89.8% and 98.0%, respectively. CONCLUSIONS: This study found ISBVS to be a feasible and safe treatment paradigm for pediatric patients with bilateral vitreoretinal pathologic features when repeated general anesthesia is undesirable or impractical.

Yonekawa Y, Kim IK. Clinical Characteristics and Current Treatment of Age-Related Macular Degeneration. Cold Spring Harb Perspect Med 2014;Abstract

Age-related macular degeneration (AMD) is a multifactorial degeneration of photoreceptors and retinal pigment epithelium. The societal impact is significant, with more than 2 million individuals in the United States alone affected by advanced stages of AMD. Recent progress in our understanding of this complex disease and parallel developments in therapeutics and imaging have translated into new management paradigms in recent years. However, there are many unanswered questions, and diagnostic and prognostic precision and treatment outcomes can still be improved. In this article, we discuss the clinical features of AMD, provide correlations with modern imaging and histopathology, and present an overview of treatment strategies.

Yonekawa Y, Shah AS, France RM, Ciarlini P, VanderVeen DK. Leukocoria in a 2-year-old boy. J Paediatr Child Health 2014;50(9):744.
Yoon MK, Piluek WJ, Ruggiero JP, McDermott MW, McCulley TJ. Orbital cerebrospinal fluid accumulation after complicated pterional-orbitozygomatic craniotomy. J Neuroophthalmol 2014;34(4):346-9.Abstract

We describe 2 patients who developed postoperative orbital cerebrospinal fluid (CSF) collection after orbitozygomatic pterional craniotomy. An 18-year-old woman underwent exploratory pterional-orbitozygomatic craniotomy. Five days postoperatively, after removal of a lumbar drain, proptosis and a compressive optic neuropathy developed. Computed tomography demonstrated a CSF collection contiguous with the craniotomy site. Resolution followed percutaneous aspiration and replacement of the lumbar drain. A 57-year-old woman underwent a pterional-orbitozygomatic craniotomy for removal of a left anterior clinoid meningioma, complicated by a large left hemorrhagic stroke requiring decompressive hemicraniectomy. Extracranial CSF collections accumulated in both the orbit and subgaleal spaces. Resolution followed placement of an external ventricular drain. Based on these cases, the mechanism seems to be the combination of iatrogenic formation of a communication with the subarachnoid space and elevated intracranial pressure. Resolution was achieved by normalizing intracranial pressure.

You C, Lamba N, Lasave AF, Ma L, Diaz MH, Foster SC. Rituximab in the treatment of ocular cicatricial pemphigoid: a retrospective cohort study. Graefes Arch Clin Exp Ophthalmol 2017;255(6):1221-1228.Abstract
PURPOSE: The purpose was to evaluate the effectiveness and safety of rituximab (RTX) for the treatment of patients with aggressive ocular cicatricial pemphigoid (OCP). METHODS: A review of patient records at a tertiary referral center with biopsy confirmed OCP who presented between 2006 and 2016. Sixty-one eyes of 32 patients with symptomatic OCP who received treatment with RTX monotherapy or RTX in combination with additional immunomodulatory treatment (IMT) were evaluated. Main outcomes included clinically evident remission of disease, the percentage of corticosteroid sparing patients, stage of OCP (Foster), best corrected visual acuity, and treatment complications. Remission was defined as absence of progressive scarring and active ocular inflammation for ≥ 2 months. Partial remission/responding was defined as disease control and clinical improvement for ≥ 2 months. RESULTS: Mean age at the initiation of RTX treatment was 59.1 years (range, 24-80 years) with a median follow-up time after RTX initiation of 32 months (range, 14 to 127 months). Twenty-six patients achieved clinical remission with an average sustained remission of 24.5 months (from 9 months to 84 months). RTX monotherapy was used in six patients, RTX in combination with intravenous immunoglobulin in 14 patients, and RTX with intravenous immunoglobulin and/or with other IMT agent in six patients. Seven eyes (11.5%) of six patients had favorable response to RTX and achieved response and partial remission, while inflammation remained active in the other seven eyes (11.5%) of four patients though there was no progressive scarring. At the last visit, three patients (9.4%) were on topical corticosteroid, three patients (9.4%) were treated with systemic corticosteroid treatments, and the other 26 patients (81.2%) achieved corticosteroid sparing therapy. Five eyes (8.2%) progressed one Foster stage. No other cicatrization progression or worsening of LogMAR visual acuity (p = 0.641) was observed during the follow-up period. Adverse events included leukopenia in three patients (9.4%), anemia in two patients (6.2%), liver enzyme elevation in three patients (9.4%) who were also on another concomitant IMT drug, and Epstein-Barr Virus infection and sinus infection in one patient each (3.1%). No other severe adverse events were noted during the follow-up period. CONCLUSIONS: These retrospective data suggest that RTX is efficacious and well tolerated when included for the treatment of OCP. Controlled studies are necessary to identify the role of this IMT agent in the therapeutic arsenal, especially its optimum dose and duration of administration.
You C, Ma L, Lasave AF, Foster SC. Rituximab Induction and Maintenance Treatment in Patients with Scleritis and Granulomatosis with Polyangiitis (Wegener's). Ocul Immunol Inflamm 2017;:1-8.Abstract
AIMS: To evaluate the efficacy and safety of rituximab (RTX) induction and maintenance treatment for patients with scleritis and granulomatosis with polyangiitis (GPA), Wegener's. METHODS: Nine patients (12 eyes) with scleritis with GPA who did not respond to corticosteroids and more than one immunosuppressive agent who received ongoing maintenance RTX treatment were identified. Demographics and outcome measures were recorded. RESULTS: Median follow-up time of 30 months (range, 15 to 87 months). All 12 eyes achieved remission during the RTX maintenance period with a median time in remission of 14 months (range, 5-76 months), and median interval between RTX initiation and inactive disease of 5 months (range, 2-8 months). Two eyes in two patients relapsed. One received steroid eye drops, and the other received a short-term increased dose of intravenous corticosteroids. CONCLUSIONS: RTX was effective as an induction and maintenance treatment in our small cohort of patients with GPA-associated scleritis.
Yu Z, Zeng Z, Zhang J, Pan Y, Chen M, Guo Y, Yu N, Chodosh J, Fu N, Che X, Zhang Q. Fatal Community-acquired Pneumonia in Children Caused by Re-emergent Human Adenovirus 7d Associated with Higher Severity of Illness and Fatality Rate. Sci Rep 2016;6:37216.Abstract

Human adenoviruses (HAdVs) are highly contagious pathogens causing acute respiratory disease (ARD), such as community-acquired pneumonia. HAdV-7d, a re-emergent genomic variant, has been recently reported in Asia and the United States after a several-decade absence. However, whether HAdV-7d is associated with higher severity than other types is currently unclear. In this study, the clinical and epidemiological investigation showed that fever, cough, and sore throat were the three most common respiratory symptoms of HAdV infections. HAdV-7 caused longer duration of fever, higher morbidity of tachypnea/dyspnea, pleural effusion, diarrhea, hepatosplenomegaly, consciousness alteration, as well as higher rates of pneumonia, mechanical ventilation and higher fatality rate (28.6%) than other types, particularly HAdV-3 and HAdV-2. The genomes of seven HAdV-7d isolates from mild, severe, and fatal cases were sequenced and highly similar with each other. Surprisingly, two isolates (2011, 2012) had 100% identical genomes with an earlier strain from a fatal ARD outbreak in China (2009), which elucidates the virus origin and confirms the unexpected HAdV genomic conservation and stability. Phylogenetic analysis indicated that L1 52/55-kDa DNA packaging protein may be associated with the higher severity of illness and fatality rate of HAdV-7. Clinicians need to be aware of HAdVs in children with ARD.

Yu G, Duguay J, Marra KV, Gautam S, Le Guern G, Begum S, Sharifzadeh A, Arroyo JG. EFFICACY AND SAFETY OF TREATMENT OPTIONS FOR VITREOMACULAR TRACTION: A Case Series and Meta-Analysis. Retina 2016;36(7):1260-70.Abstract

PURPOSE: To evaluate treatment options for vitreomacular traction (VMT). METHODS: A retrospective, consecutive case series and a literature search with Boolean search logic. A random-effects meta-analysis was conducted to combine the rates of VMT resolution per treatment. Patients from studies analyzed were placed into cohorts based on the treatment received. RESULTS: CASE SERIES: Zero of 10 control, 3 of 7 intravitreal ocriplasmin (IVO, P = 0.10), 7 of 8 intravitreal expansile gas (pneumatic vitreolysis, PV, P < 0.01), and 10 of 10 pars plana vitrectomy (P < 0.01)-treated eyes experienced VMT release (VMTr) at Day 28. No patients developed retinal tears or detachment. One PV-treated (12.5%) eye developed a macular hole. Meta-analysis: Twenty-three of 131 prospective or retrospective and consecutive articles were included. Sixty-three eyes were treated with PV, 726 eyes were treated with intravitreal ocriplasmin, and 253 eyes were characterized as the control group (saline injection). The weighted rate of VMT resolution for the control group was 0.09 (95% confidence interval [CI]: 0.06-0.13), PV was 0.84 (95% CI: 0.76-0.92), and intravitreal ocriplasmin was 0.26 (95% CI: 0.23-0.29). CONCLUSION: Our analysis found that PV releases VMT in most patients and suggest that PV may be as effective or superior to nonsurgical options for VMTr at Day 28 with a similar risk profile.

Yu D, Zheng J, Zhu R, Wu N, Guan A, Cho K-S, Chen DF, Luo G. Computer-aided analyses of mouse retinal OCT images - an actual application report. Ophthalmic Physiol Opt 2015;35(4):442-9.Abstract

PURPOSE: There is a need for automated retinal optical coherence tomography (OCT) image analysis tools for quantitative measurements in small animals. Some image processing techniques for retinal layer analysis have been developed, but reports about how useful those techniques are in actual animal studies are rare. This paper presents the use of a retinal layer detection method we developed in an actual mouse study that involves wild type and mutated mice carrying photoreceptor degeneration. METHODS: Spectral domain OCT scanning was performed by four experimenters over 12 months on 45 mouse eyes that were wild-type, deficient for ephrin-A2 and ephrin-A3, deficient for rhodopsin, or deficient for rhodopsin, ephrin-A2 and ephrin-A3. The thickness of photoreceptor complex between the outer plexiform layer and retinal pigment epithelium was measured on two sides of the optic disc as the biomarker of retinal degeneration. All the layer detection results were visually confirmed. RESULTS: Overall, 96% (8519 out of 9000) of the half-side images were successfully processed using our technique in a semi-automatic manner. There was no significant difference in success rate between mouse lines (p = 0.91). Based on a human observer's rating of image quality for images successfully and unsuccessfully processed, the odds ratios for 'easily visible' images and 'not clear' images to be successfully processed is 62 and 4, respectively, against 'indistinguishable' images. Thickness of photoreceptor complex was significantly different across the quadrants compared (p < 0.001). It was also found that the average thickness based on 4-point sparse sampling was not significantly different from the full analysis, while the range of differences between the two methods could be up to about 6 μm or 16% for individual eyes. Differences between mouse lines and progressive thickness reduction were revealed by both sampling measures. CONCLUSIONS: Although the thickness of the photoreceptor complex layer is not even, manual sparse sampling may be as sufficiently accurate as full analysis in some studies such as ours, where the error of sparse sampling was much smaller than the effect size of rhodopsin deficiency. It is also suggested that the image processing method can be useful in actual animal studies. Even for images poorly visible to human eyes the image processing method still has a good chance to extract the complex layer.

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Zahr A, Alcaide P, Yang J, Jones A, Gregory M, Dela Paz NG, Patel-Hett S, Nevers T, Koirala A, Luscinskas FW, Saint-Geniez M, Ksander B, D'Amore PA, Argüeso P. Endomucin prevents leukocyte-endothelial cell adhesion and has a critical role under resting and inflammatory conditions. Nat Commun 2016;7:10363.Abstract

Endomucin is a membrane-bound glycoprotein expressed luminally by endothelial cells that line postcapillary venules, a primary site of leukocyte recruitment during inflammation. Here we show that endomucin abrogation on quiescent endothelial cells enables neutrophils to adhere firmly, via LFA-1-mediated binding to ICAM-1 constitutively expressed by endothelial cells. Moreover, TNF-α stimulation downregulates cell surface expression of endomucin concurrent with increased expression of adhesion molecules. Adenovirus-mediated expression of endomucin under inflammatory conditions prevents neutrophil adhesion in vitro and reduces the infiltration of CD45(+) and NIMP-R14(+) cells in vivo. These results indicate that endomucin prevents leukocyte contact with adhesion molecules in non-inflamed tissues and that downregulation of endomucin is critical to facilitate adhesion of leukocytes into inflamed tissues.

Zajac L, Koo B-B, Bauer CM, Killiany R, Killiany R. Seed Location Impacts Whole-Brain Structural Network Comparisons between Healthy Elderly and Individuals with Alzheimer's Disease. Brain Sci 2017;7(4)Abstract

Whole-brain networks derived from diffusion tensor imaging (DTI) data require the identification of seed and target regions of interest (ROIs) to assess connectivity patterns. This study investigated how initiating tracts from gray matter (GM) or white matter (WM) seed ROIs impacts (1) structural networks constructed from DTI data from healthy elderly (control) and individuals with Alzheimer's disease (AD) and (2) between-group comparisons using these networks. DTI datasets were obtained from the Alzheimer's disease Neuroimaging Initiative database. Deterministic tractography was used to build two whole-brain networks for each subject; one in which tracts were initiated from WM ROIs and another in which they were initiated from GM ROIs. With respect to the first goal, in both groups, WM-seeded networks had approximately 400 more connections and stronger connections (as measured by number of streamlines per connection) than GM-seeded networks, but shared 94% of the connections found in the GM-seed networks. With respect to the second goal, between-group comparisons revealed a stronger subnetwork (as measured by number of streamlines per connection) in controls compared to AD using both WM-seeded and GM-seeded networks. The comparison using WM-seeded networks produced a larger (i.e., a greater number of connections) and more significant subnetwork in controls versus AD. Global, local, and nodal efficiency were greater in controls compared to AD, and between-group comparisons of these measures using WM-seeded networks had larger effect sizes than those using GM-seeded networks. These findings affirm that seed location significantly affects the ability to detect between-group differences in structural networks.

Zandi S, Nakao S, Chun K-H, Fiorina P, Sun D, Arita R, Zhao M, Kim E, Schueller O, Campbell S, Taher M, Melhorn MI, Schering A, Gatti F, Tezza S, Xie F, Vergani A, Yoshida S, Ishikawa K, Yamaguchi M, Sasaki F, Schmidt-Ullrich R, Hata Y, Enaida H, Yuzawa M, Yokomizo T, Kim Y-B, Sweetnam P, Ishibashi T, Hafezi-Moghadam A. ROCK-Isoform-Specific Polarization of Macrophages Associated with Age-Related Macular Degeneration. Cell Rep 2015;10(7):1173-86.Abstract

Age is a major risk factor in age-related macular degeneration (AMD), but the underlying cause is unknown. We find increased Rho-associated kinase (ROCK) signaling and M2 characteristics in eyes of aged mice, revealing immune changes in aging. ROCK isoforms determine macrophage polarization into M1 and M2 subtypes. M2-like macrophages accumulated in AMD, but not in normal eyes, suggesting that these macrophages may be linked to macular degeneration. M2 macrophages injected into the mouse eye exacerbated choroidal neovascular lesions, while M1 macrophages ameliorated them, supporting a causal role for macrophage subtypes in AMD. Selective ROCK2 inhibition with a small molecule decreased M2-like macrophages and choroidal neovascularization. ROCK2 inhibition upregulated M1 markers without affecting macrophage recruitment, underlining the plasticity of these macrophages. These results reveal age-induced innate immune imbalance as underlying AMD pathogenesis. Targeting macrophage plasticity opens up new possibilities for more effective AMD treatment.

Zareian R, Susilo ME, Paten JA, McLean JP, Hollmann J, Karamichos D, Messer CS, Tambe DT, Saeidi N, Zieske JD, Ruberti JW. Human Corneal Fibroblast Pattern Evolution and Matrix Synthesis on Mechanically Biased Substrates. Tissue Eng Part A 2016;22(19-20):1204-1217.Abstract

In a fibroblast colony model of corneal stromal development, we asked how physiological tension influences the patterning dynamics of fibroblasts and the orientation of deposited extracellular matrix (ECM). Using long-term live-cell microscopy, enabled by an optically accessible mechanobioreactor, a primary human corneal fibroblast colony was cultured on three types of substrates: a mechanically biased, loaded, dense, disorganized collagen substrate (LDDCS), a glass coverslip, and an unloaded, dense, disorganized collagen substrate (UDDCS). On LDDCS, fibroblast orientation and migration along a preferred angle developed early, cell orientation was correlated over long distances, and the colony pattern was stable. On glass, fibroblast orientation was poorly correlated, developed more slowly, and colony patterns were metastable. On UDDCS, cell orientation was correlated over shorter distances compared with LDDCS specimens. On all substrates, the ECM pattern reflected the cell pattern. In summary, mechanically biasing the collagen substrate altered the early migration behavior of individual cells, leading to stable emergent cell patterning, which set the template for newly synthesized ECM.

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