Topical Ivermectin-metronidazole gel therapy improves Meibomian gland Function in blepharitis caused by demodex spp.

Purpose: To evaluate the efficacy and safety of topical Ivermectin- Metronidazol in the management of demodex infestation and their effect in Meibomian gland dysfunction (MGD) METHODS: Fifty-four patients (108 eyes) with demodex diagnosis and Meibomian gland dysfunction received Ivermectin 0.3 %+Metronidazole 0.5 % gel in the night for 5 weeks.

A Core of Keratocan-Negative Cells Survives in Old Corneal Scars.

Corneal scars originate from keratocyte-derived fibroblasts and myofibroblasts that are ultimately cleared through apoptosis or revert to keratocytes. A mouse model expressing the keratocyte lineage-specific reporter KeraRT/tetO-Cre/mTmG (I-KeramTmG) was interrogated to elucidate cell phenotype dynamics during scar maturation. This model expresses tdTomato (red) in all keratocan-negative cells, while enhanced green fluorescent protein (green) is expressed only by keratocytes.

Dysfunctional latent transforming growth factor β activation after corneal injury in a classical Ehlers-Danlos model.

Patients with classical Ehlers Danlos syndrome (cEDS) suffer impaired wound healing and from scars formed after injuries that are atrophic and difficult to close surgically. Haploinsufficiency in COL5A1 creates systemic morphological and functional alterations in the entire body. We investigated mechanisms that impair wound healing from corneal lacerations (full thickness injuries) in a mouse model of cEDS (Col5a1).

Keratocyte-Derived Myofibroblasts: Functional Differences With Their Fibroblast Precursors.

Purpose: In this study, we aim to elucidate functional differences between fibroblasts and myofibroblasts derived from a keratocyte lineage to better understand corneal scarring.

Methods: Corneal fibroblasts, derived from a novel triple transgenic conditional KeraRT/tetO-Cre/mTmG mouse strain that allows isolation and tracking of keratocyte lineage, were expanded, and transformed by exposure to transforming growth factor (TGF)-β1 to myofibroblasts. The composition and organization of a fibroblast-built matrix, deposited by fibroblasts in vitro, was analyzed and compared to the composition of an in vitro matrix built by myofibroblasts.

Stromal matrix directs corneal fibroblasts to re-express keratocan after injury and transplantation.

Every tissue has an extracellular matrix (ECM) with certain properties unique to it - the tissue 'niche' - that are necessary for normal function. A distinct specific population of quiescent keratocan-expressing keratocytes populate the corneal stroma during homeostasis to maintain corneal function. However, during wound healing, when there is alteration of the niche conditions, keratocytes undergo apoptosis, and activated corneal fibroblasts and myofibroblasts attempt to restore tissue integrity and function.

Molecular nature of ocular surface barrier function, diseases that affect it, and its relevance for ocular drug delivery.

The structural and functional integrity of the ocular surface, a continuous epithelial structure comprised of the cornea, the conjunctiva, and the ductal surface of the lacrimal as well as meibomian glands, is crucial for proper vision. The ocular surface barrier function (OSBF), sum of the different types of protective mechanisms that exist at the ocular surface, is essential to protect the rest of the eye from vision-threatening physical, chemical, and biological insults. OSBF helps maintain the immune privileged nature of the cornea and the aqueous humor by preventing entry of infectious agents, allergens, and noxious chemicals.

Collagen XII regulates stromal wound closure.

The role of collagen XII in regulating injury repair and reestablishment of corneal function is unknown. This manuscript aims to investigate the role(s) of collagen XII in the repair of incisional and debridement injuries in an adult mouse model. Two different types of injury in wild type and Col12a1 corneas were created to investigate the effects of collagen XII -in wound repair and scar formation-by using clinical photographs, immunohistology, second harmonic generation imaging and electron microscopy.

Genipin increases extracellular matrix synthesis preventing corneal perforation.

Purpose: Corneal melting and perforation are feared sight-threatening complications of infections, autoimmune disease, and severe burns. Assess the use of genipin in treating stromal melt.

Methods: A model for corneal wound healing was created through epithelial debridement and mechanical burring to injure the corneal stromal matrix in adult mice.

Multiple Optical Elastography Techniques Reveal the Regulation of Corneal Stiffness by Collagen XII.

Purpose: Collagen XII plays a role in regulating the structure and mechanical properties of the cornea. In this work, several optical elastography techniques were used to investigate the effect of collagen XII deficiency on the stiffness of the murine cornea.

Methods: A three-prong optical elastography approach was used to investigate the mechanical properties of the cornea.

Downregulation of collagen XI during late postnatal corneal development is followed by upregulation after injury.

Collagen XI plays a role in nucleating collagen fibrils and in controlling fibril diameter. The aim of this research was to elucidate the role that collagen XI plays in corneal fibrillogenesis during development and following injury. The temporal and spatial expression of collagen XI was evaluated in C57BL/6 wild-type mice.

Collagen XII Regulates Corneal Stromal Structure by Modulating Transforming Growth Factor-β Activity.

Collagen XII is a regulator of corneal stroma structure and function. The current study examined the role of collagen XII in regulating corneal stromal transforming growth factor (TGF)-β activation and latency. Specifically, with the use of conventional collagen XII null mouse model, the role of collagen XII in the regulation of TGF-β latency and activity in vivo was investigated.

Clinical Outcomes and Patient Satisfaction After Corneal Neurotization.

Purpose: The aim of this study was to assess clinical outcomes of corneal neurotization (CN) and determine patient perception of postoperative results.

Methods: This was a retrospective study involving 29 eyes in 28 patients who underwent CN. Chart review data included demographic and clinical history; ophthalmic examination including visual acuity, ocular surface quality, and corneal sensation; surgical technique; and postoperative course.

Collagen XIV Is an Intrinsic Regulator of Corneal Stromal Structure and Function.

Collagen XIV is poorly characterized in the body, and the current knowledge of its function in the cornea is limited. The aim of the current study was to elucidate the role(s) of collagen XIV in regulating corneal stromal structure and function. Analysis of collagen XIV expression, temporal and spatial, was performed at different postnatal days (Ps) in wild-type C57BL/6 mouse corneal stromas and after injury.

Collagen V insufficiency in a mouse model for Ehlers Danlos-syndrome affects viscoelastic biomechanical properties explaining thin and brittle corneas.

Ehlers-Danlos syndrome (EDS) is a genetic disease leading to abnormalities in mechanical properties of different tissues. Here we quantify corneal biomechanical properties in an adult classic EDS mouse model using two different measurement approaches suited for murine corneal mechanical characterization and relate differences to stromal structure using Second Harmonic Generation (SHG) microscopy. Quasi-static Optical Coherence Elastography (OCE) was conducted non-invasively during ambient pressure modulation by - 3 mmHg.

Fungal keratitis: Mechanisms of infection and management strategies.

Fungal corneal ulcers are an uncommon, yet challenging, cause of vision loss. In the United States, geographic location appears to dictate not only the incidence of fungal ulcers, but also the fungal genera most encountered. These patterns of infection can be linked to environmental factors and individual characteristics of fungal organisms.

Genipin Delays Corneal Stromal Enzymatic Digestion.

Purpose: To evaluate the use of genipin in delaying enzymatic digestion of corneal stroma.

Methods: Human corneal stromal tissue was treated with genipin, a known chemical crosslinker, and then along with control tissue was subjected to enzymatic digestion with collagenase. The effects of genipin treatment in retarding stromal digestion were analyzed with phase contrast microscopy, a protein quantification assay, second harmonic generation imaging, and transmission electron microscopy.

Stromal microsporidial keratitis successfully treated with medical therapy.

Purpose: To report a case of severe stromal microsporidal keratitis successfully treated with oral albendazole and topical voriconazole.

Observations: A 71-year-old man presented with progressive vision loss and corneal opacification for one year. Initial visual acuity was counting fingers attributed to a dense subepithelial opacification.

Diseases of the corneal endothelium.

The corneal endothelial monolayer and associated Descemet's membrane (DM) complex is a unique structure that plays an essential role in corneal function. Endothelial cells are neural crest derived cells that rest on a special extracellular matrix and play a major role in maintaining stromal hydration within a narrow physiologic range necessary for clear vision. A number of diseases affect the endothelial cells and DM complex and can impair corneal function and vision.

Creation and grading of experimental corneal scars in mice models.

Purpose: To develop a stromal wound healing model and a reliable scar classification score system that correlates photographic evaluation with changes in the structure and organization of the extracellular matrix.

Materials And Methods: We tested three stromal injury techniques in adult C57BL/6 mice. Technique 1, a lineal partial thickness keratotomy in the horizontal axis.

Composition, structure and function of the corneal stroma.

No other tissue in the body depends more on the composition and organization of the extracellular matrix (ECM) for normal structure and function than the corneal stroma. The precise arrangement and orientation of collagen fibrils, lamellae and keratocytes that occurs during development and is needed in adults to maintain stromal function is dependent on the regulated interaction of multiple ECM components that contribute to attain the unique properties of the cornea: transparency, shape, mechanical strength, and avascularity. This review summarizes the contribution of different ECM components, their structure, regulation and function in modulating the properties of the corneal stroma.

Endothelial-Stromal Communication in Murine and Human Corneas.

The purpose of this study is to identify and characterize interactions of corneal endothelial cells with the posterior stroma. Corneal endothelial-stromal interactions were examined in developing postnatal day 3 (P3) and mature postnatal day 30 (P30) C57BL/6 mice and adult human corneas. Flat mounts and cross-sections were studied using immunofluorescence microscopy.