One threat, different answers: the impact of COVID-19 pandemic on cornea donation and donor selection across Europe.

Objectives: To assess to which extent the COVID-19 pandemic affected corneal transplantation by virtue of donor selection algorithms in different European countries.

Design: Survey.

Setting: 110 eye banks in 26 European countries.

The HYLAN M Study: Efficacy of 0.15% High Molecular Weight Hyaluronan Fluid in the Treatment of Severe Dry Eye Disease in a Multicenter Randomized Trial.

The aim of the HYLAN M study was to investigate if symptoms and/or signs of patients suffering from severe dry eye disease (DED) can be improved by substituting individually optimized artificial tear therapy by high molecular weight hyaluronan (HMWHA) eye drops. In this international, multicenter study, patients with symptoms of at least ocular surface disease index (OSDI) 33 and corneal fluorescein staining (CFS) of at least Oxford grade 3 were included. A total of 84 per-protocol patients were randomized in two study arms.

SOCS3 in retinal neurons and glial cells suppresses VEGF signaling to prevent pathological neovascular growth.

Neurons and glial cells in the retina contribute to neovascularization, or the formation of abnormal new blood vessels, in proliferative retinopathy, a condition that can lead to vision loss or blindness. We identified a mechanism by which suppressor of cytokine signaling 3 (SOCS3) in neurons and glial cells prevents neovascularization. We found that Socs3 expression was increased in the retinal ganglion cell and inner nuclear layers after oxygen-induced retinopathy.

Fibroblast activation protein-α, a stromal cell surface protease, shapes key features of cancer associated fibroblasts through proteome and degradome alterations.

Cancer associated fibroblasts (CAFs) constitute an abundant stromal component of most solid tumors. Fibroblast activation protein (FAP) α is a cell surface protease that is expressed by CAFs. We corroborate this expression profile by immunohistochemical analysis of colorectal cancer specimens.

Modulation of focal adhesion constituents and their down-stream events by EGF: On the cross-talk of integrins and growth factor receptors.

Within the concept of integrin growth factor receptor (GFR) cross-talk, little is known about the effects of GFRs on focal adhesions (FAs). Therefore, we tested the hypothesis whether EGF can modulate constituents of FAs and subsequent down-stream events. To this end, EGF-treated keratinocytes were subjected to combined fluorescence imaging and western blotting, to quantify expression and/or activation of molecules, involved in integrin GFR cross-talk, and receptor proximal and distal signaling events.

Estrogen intake and copper depositions: implications for Alzheimer's disease?

We present a patient with chronic postmenopausal estrogen intake with presence of Kayser-Fleischer ring in the cornea and Alzheimer's disease and discuss the pathophysiological mechanisms of estrogen intake and copper accumulation in various tissues, including the central nervous system. Sonography was compatible with copper accumulation in the basal ganglia, but the patient showed no clinical signs of Wilson's disease. Magnetic resonance imaging and positron emission tomography revealed a typical pattern for Alzheimer's disease.

Host-derived endothelial regeneration of corneal transplants in a rat keratoplasty model.

Background: It has been observed that formerly rejected opaque corneal transplants can regain clarity in the rat. We hypothesized that graft endothelium is regenerated by the host. Therefore, we used green fluorescent protein (GFP) transgenic rats to assess the origin of cells following keratoplasty.

Regeneration of corneal endothelial cells following keratoplasty in rats with bullous keratopathy.

Purpose: Little is known about the behavior of the endothelial cell (EC) layer following keratoplasty. In vitro experiments suggested that the peripheral endothelium might have a higher regenerative capacity than the central endothelium, and some authors hypothesized that endothelial progenitor cells are present in the limbal area. Thus, we analyzed the corneal endothelial regenerative capacity in vivo in a rat model of bullous keratopathy using either bullous central grafts or bullous peripheral recipient corneas to analyze differences in EC regeneration depending on central versus peripheral cell origin.

Surgical management of corneal limbal dermoids: retrospective study of different techniques and use of Mitomycin C.

Purpose: We retrospectively studied the efficacy and safety of different surgical approaches to treating pediatric limbal dermoids with regard to intra and postoperative complications.

Methods: The data of 12 consecutive patients (14 eyes), who underwent monocentric surgery of a limbal demoid in the past 9 years, were retrospectively analyzed for intra and postoperative complications. Group one consists of eleven eyes: seven eyes with a bare-sclera deep lamellar excision of the dermoid and four eyes with an additional amniotic membrane transplantation subsequent to excision.

Dynamic formation of macular microcysts independent of vitreous traction changes.

Objective: To test the assumption of vitreous traction as a cause of macular microcysts in neuroinflammatory diseases and to establish a testable model to quantify vitreous traction changes.

Methods: Retrospective cohort study including 9 patients with neuroinflammatory diseases and macular microcysts that were longitudinally analyzed using optical coherence tomography. A mechanical model was developed to test the theory of vitreous traction vs macular swelling.

Cytochrome P450 2C8 ω3-long-chain polyunsaturated fatty acid metabolites increase mouse retinal pathologic neovascularization--brief report.

Objective: Regulation of angiogenesis is critical for many diseases. Specifically, pathological retinal neovascularization, a major cause of blindness, is suppressed with dietary ω3-long-chain polyunsaturated fatty acids (ω3LCPUFAs) through antiangiogenic metabolites of cyclooxygenase and lipoxygenase. Cytochrome P450 epoxygenases (CYP2C8) also metabolize LCPUFAs, producing bioactive epoxides, which are inactivated by soluble epoxide hydrolase (sEH) to transdihydrodiols.

Progesterone and estrogen receptors in conjunctival melanoma and nevi.

Background: Since it has been observed that melanocytic lesions can alter their appearance during pregnancy, we analyzed whether hormone receptors are expressed in conjunctival nevi as well as conjunctival melanoma. We further analyzed whether the number of estrogen (ER) or progesterone receptors (PR) might be associated with the disease course in conjunctival melanoma.

Methods: Twenty-seven paraffin-embedded samples of conjunctival nevi and 27 conjunctival melanoma specimens were examined using immunohistological analysis with antibodies against PR and ER.

LRG1 promotes angiogenesis by modulating endothelial TGF-β signalling.

Aberrant neovascularization contributes to diseases such as cancer, blindness and atherosclerosis, and is the consequence of inappropriate angiogenic signalling. Although many regulators of pathogenic angiogenesis have been identified, our understanding of this process is incomplete. Here we explore the transcriptome of retinal microvessels isolated from mouse models of retinal disease that exhibit vascular pathology, and uncover an upregulated gene, leucine-rich alpha-2-glycoprotein 1 (Lrg1), of previously unknown function.

Cathepsin proteases promote angiogenic sprouting and laser-induced choroidal neovascularisation in mice.

Cysteine cathepsins are a family of proteases involved in intracellular protein turnover and extracellular matrix degradation. Cathepsin B (Ctsb) and cathepsin Z (Ctsz) promote tumorigenesis and Ctsb is a known modulator of tumor angiogenesis. We therefore investigated the angiomodulatory function of these cathepsins in vitro as well as in a mouse model of laser-induced choroidal neovascularization (laser-CNV).

The diagnosis and treatment of giant cell arteritis.

Background: Giant cell arteritis (GCA) is the most common systemic vasculitis in persons aged 50 and above (incidence, 3.5 per 100,000 per year). It affects cranial arteries, the aorta, and arteries elsewhere in the body, e.

Descemet stripping endothelial keratoplasty--rapid recovery of visual acuity.

Background: Technical innovations in corneal transplantation have now made it possible to replace only the diseased part of the cornea, rather than the entire cornea as in penetrating keratoplasty (PKP). Patients with endothelial insufficiency due to Fuchs endothelial dystrophy, bullous keratopathy, or endothelial failure after keratoplasty can be treated with the new methods of posterior lamellar corneal transplantation: Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK). It remains unclear which of these methods is better in the individual case.

Visual outcome and histological findings following femtosecond laser-assisted versus microkeratome-assisted DSAEK.

Background: The aim of this study was to compare the visual outcome of femtosecond laser-assisted Descemet stripping automated endothelial keratoplasty (DSAEK) to microkeratome-assisted DSAEK as well as to contrast precut versus surgeon-cut grafts. Histologic characterization of failed DSAEK grafts was performed in order to correlate ultrastructural changes with graft failures.

Methods: In this case control study, 47 cases of DSAEK were investigated in terms of visual acuity, keratometric astigmatism, spherical equivalent, endothelial cell count, and postoperative complications.

Semaphorin 3F forms an anti-angiogenic barrier in outer retina.

Semaphorins are known modulators of axonal sprouting and angiogenesis. In the retina, we identified a distinct and almost exclusive expression of Semaphorin 3F in the outer layers. Interestingly, these outer retinal layers are physiologically avascular.

Comparative measurement of intraocular pressure by Icare tonometry and Airpuff tonometry in healthy subjects and patients wearing therapeutic soft contact lenses.

Background: The aim of the present study was to compare the measurement of intraocular pressure (IOP) through a therapeutic soft contact lens with the "native" measurement. We additionally investigate whether a rebound tonometer (RT) or non-contact tonometer (NCT) is more suitable to measure IOP through a bandage contact lens.

Methods: The IOP was determined using each of the two methods, three times successively with (lens measurement) and without (native measurement) a soft contact lens.

Evaluation of intraocular pressure elevation in a modified laser-induced glaucoma rat model.

The main drawbacks of currently described pressure induced glaucoma animal models are, that intraocular pressure (IOP) either rises slowly, leading to a heterogeneous onset of glaucoma in the treated animals or that IOP normalizes before significant damage occurs, necessitating re-treatment. Furthermore, a variable magnitude of IOP increase often results when particles are introduced into the anterior chamber. In order to develop a simple and reproducible rat glaucoma model with sustained IOP elevation after a single treatment we induced occlusion of the chamber angle by anterior chamber paracentesis and subsequent laser coagulation of the limbal area with 35, 40 or 45 laser burns.

Quantification of retrograde axonal transport in the rat optic nerve by fluorogold spectrometry.

Purpose: Disturbed axonal transport is an important pathogenic factor in many neurodegenerative diseases, such as glaucoma, an eye disease characterised by progressive atrophy of the optic nerve. Quantification of retrograde axonal transport in the optic nerve usually requires labour intensive histochemical techniques or expensive equipment for in vivo imaging. Here, we report on a robust alternative method using Fluorogold (FG) as tracer, which is spectrometrically quantified in retinal tissue lysate.