• Journal of Veterinary Clinics
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• v.35 no.6
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• pp.311-314
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• 2018

Squamous cell carcinoma (SCC) is a form of neoplasm that origins from the epithelial surface of many organs. Ocular occurrence in small animals is rare, especially in the central cornea without the involvement of limbus or conjunctiva. In the current case, a 10-year-old, spayed female Shih-Tzu was presented with a central corneal mass. Through an ophthalmic examination the sign of corneal scarring around the mass was found. Pink fleshy lesion that protruded outward was removed through superficial keratectomy. The mass with the size of $8.5{\times}6.5$ millimeter was histopathologically diagnosed as corneal SCC infiltrating not only the epithelium, but also the superficial corneal stroma with surrounding superficial lymphoplasmacytic and neutrophilic chronic keratitis. Also, the adjacent, non-affected corneal epithelium was markedly hyperplastic and keratinized; the adjacent stroma was moderately vascularized and fibrotic. The pulse-dose therapy using 1% topical 5-flourouracil were applied for five cycles. The tumor has not recurred through nine months of follow-up time.

• Applied Microscopy
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• v.44 no.3
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• pp.88-95
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• 2014

This study examined the effects of quercetin on corneal opacity caused by corneal edema by suppressing the damage on corneal endothelial cell, which was induced by mitomycin-C (MMC). In the MMC-treated group, the number of keratocytes was noticeably fewer compared to that of other groups. Although this group showed normal amount of fiber in the corneal stroma, the thickness was shown to be very thick and the alignment of the corneal endothelial cells that worked as the barrier against aqueous humor was irregular. According to such results, it was known that corneal opacity induced by MMC is not caused by proliferation of keratocytes, but by corneal edema triggered by the infiltration of aqueous humor. In the MMC+quercetin and quercetin+MMC-treated groups, the number of keratocytes was higher and polymorphonuclear leukocytes infilteration was lower significantly compared to that of the MMC-treated group. Although the amounts of fiber and endothelioid cell arrangement were normal, there was more space observed in the corneal stroma. Nonetheless, these groups showed significantly lower stromal thickness compared to that of the MMC group. In conclusion, quercetin has the effect on the reduction of corneal opacity caused by corneal edema that work MMC-induced damage to the corneal endothelial cells.

• Journal of the korean veterinary medical association
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• v.47 no.1
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• pp.42-46
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• 2011

임상에 있어 눈에 적용하는 약물의 적용은 정상적인 조직을 손상시키지 않으면서 원하는 안구 조직에 목표로 하는 용량의 안약을 전달하는 것이 목적이라고 할 수 있다. 그러나 이러한 간단한 목적도 실제로 환자의 성격, 안구 조직의 민감성, 그리고 친지질성 각막 외피세포(lipophilic corneal epithelium), 친수성 각막 그리고 공막의 간질층(hydrophilic corneal and sclera stroma), 결막의 임파 조직, 맥락막의 혈관 등, Blood-ocular barrier등 안구의 조직 자체의 장벽들로 인해 어려움을 내포하고 있는 것 역시 사실이다. 평소에 처방하고 있는 안약들을 조금 더 효과적으로 전달하기 위해 필요한 눈에 대한 이해에 대해 다루어 보도록 한다.

• BMB Reports
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• v.42 no.12
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• pp.800-805
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• 2009

This study investigated the effect of subconjunctival injections of bevacizumab, an anti-VEGF antibody, on processes involved in corneal wound healing after alkali burn injury. Mice were divided into three groups: Group 1 was the saline-treated control, group 2 received subconjunctival injection of bevacizumab 1hr after injury and group 3 received bevacizumab 1 hr and 4 days after injury. Cornea neovascularization and opacity were observed using a slit lamp microscope. Corneal repair was assessed through histological analysis and immunostaining for CD31, $\alpha$-SMA, collagen I, and TGF-$\beta$2 7 days post-injury. In group 3, injection of bevacizumab significantly lowered neovascularization and improved corneal transparency. Immunostaining analysis demonstrated a reduction in CD31, $\alpha$-SMA and TGF-$\beta$2 levels in stroma compared to group 1. These results indicate that bevacizumab may be useful in reducing neovascularization and improving corneal transparency following corneal alkali burn injury by accelerating regeneration of the basement membrane.

• Korean Journal of Veterinary Research
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• v.56 no.3
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• pp.155-160
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• 2016

This study was conducted to evaluate three different mixed formulations of sodium hyaluronate (SH) and carboxymethyl cellulose (CMC) using a low-humidity air flow-induced rat dry eye model and determine the most suitable mixture. The total thickness of the cornea, corneal epithelial thickness, corneal stroma thickness, damaged corneal epithelium percentage region, thickness of the bulbar conjunctiva epithelium, number of goblet cells, goblet cell occupation percentage region, and damaged bulbar conjunctiva epithelium percentage region were measured by histomorphological evaluation. After 5 h exposure to drying airflow, the thickness of the cornea and conjunctiva was decreased with desquamation of the corneal and conjunctiva epithelium. However, these dry eye symptoms were markedly inhibited by treatment with the reference and test formulations. More favorable effects on decreased thickness were detected in response to the CMC than the SH. However, SH had a greater protective effect against corneal and conjunctiva epithelial damage. The application of a mixture of 0.1% SH and 0.2% CMC showed more favorable effects on the corneal and conjunctival damage and the stabilization of the ocular surface than SH or CMC alone.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.289-292
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• 2002

The corneal tissue consists of three layers : epithelium, stroma, and endothelium. Central cornea is a highly differentiated tissue whereas the limbus contains the epithelial stem cell. In the present study. we report the engineering of the three-dimensional reconstructed cornea derived from rabbit limbal epithelial and stromal cells. The differentiation degree of corneal stem cells were assessed in serum concentration and inoculation density of stromal cells. Optimal condition differentiation of corneal stem cells is achieved when 5% FBS was supplemented to culture medium and $1-2{\times}10^5$ cells/ml inoculation density of stromal cells.

• Journal of Veterinary Science
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• v.23 no.4
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• pp.62.1-62.10
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• 2022

Background: The corneal and limbal morphology relevant to corneal epithelial maintenance in ten different species was examined using histological methods. Objectives: The presence of a Bowman's layer, limbal epithelial cell, and superficial stromal morphology was examined in the following species to evaluate the differences in corneal thickness and epithelium: Java sparrows, frogs, macaws, spoonbills, red pandas, penguins, horses, Dobermans, orangutans, and humans. Methods: Corneal sections (4 ㎛) were obtained from ten ocular globes from three different animal classes: Aves, Amphibia, and Mammalia. All sections were stained with hematoxylin and eosin and periodic acid-Schiff reaction. After microscopy, all stained slides were photographed and analyzed. Results: Significant morphological differences in the corneal and limbal epithelia and their underlying stroma between species were observed. The number of corneal epithelial cell layers and the overall corneal epithelial thickness varied significantly among the species. The presence of a Bowman's layer was only observed in primates (orangutans and humans). Presumed supranuclear melanin caps were noted in four species (orangutans, macaws, red pandas, and horses) in the limbal basal epithelial layer (putative site of corneal epithelial stem cells). The melanin granules covered the apex of the cell nucleus. Conclusions: Supranuclear melanin capping has been described as a process within the epidermis to reduce the concentration of ultraviolet-induced DNA photoproducts. Similarly, there may be a relationship between limbal stem cell melanin capping as a protective mechanism against ultra-violet radiation.

• Applied Microscopy
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• v.28 no.4
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• pp.491-502
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• 1998

The present study was conducted to investigate the structural changes in rat cornea. Sixty eyes from one-day-old uneyed rats, fourty eyes from 4-weeks-old rats, and foully eyes from 10-weeks-old adult rats were used. With the increase of age, the epithelial layer was thickened by the addition of new successive cellular layers. Then, the new-born rat's epithelial cells formed a pentagonal shape, and the quality of decidual cells showed a high electron-density, although the boundary between cells was distinctive. The newly produced cells showed a low electron-density so that there was the distinctive difference between light and darkness. In Bowman's layer, collagen fibrils demonstrate a regularly arranged structure along with the age. In stroma's layer, the density of keratocytes was decreased and thereby Progressively flattened during the development. The collagenous layer of the adult rats was more distinctive than that of the new-born rats in a form of parallel alignment running vertically and horizontally.

• Molecules and Cells
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• v.26 no.1
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• pp.67-73
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• 2008

Herpetic stromal keratitis (HSK) is an inflammatory disorder induced by HSV-1 infection and characterized by T cell-dependent destruction of corneal tissues. It is not known what triggers $CD4^+$ T cell migration into the stroma of HSV-1-infected corneas. The keratocyte is a fibroblast-like cell that can function as an antigen-presenting cell in the mouse cornea by expressing MHC class II and costimulatory molecules after HSV-1 infection. We hypothesized that chemokines produced by stromal keratocytes are involved in $CD4^+$ T cell infiltration into the cornea. We found that keratocytes produce several cytokines and chemokines, including MCP-1, RANTES, and T cell activation (TCA)-3. HSV-1 infection increased the production of MCP-1 and RANTES by keratocytes, and these acted as chemoattractants for HSV-1-primed $CD4^+$ T cells expressing CCR2 and CCR5. ExpreHerpetic stromal keratitis (HSK) is an inflammatory disorder induced by HSV-1 infection and characterized by T cell-dependent destruction of corneal tissues. It is not known what triggers $CD4^+$ T cell migration into the stroma of HSV-1-infected corneas. The keratocyte is a fibroblast-like cell that can function as an antigen-presenting cell in the mouse cornea by expressing MHC class II and costimulatory molecules after HSV-1 infection. We hypothesized that chemokines produced by stromal keratocytes are involved in $CD4^+$ T cell infiltration into the cornea. We found that keratocytes produce several cytokines and chemokines, including MCP-1, RANTES, and T cell activation (TCA)-3. HSV-1 infection increased the production of MCP-1 and RANTES by keratocytes, and these acted as chemoattractants for HSV-1-primed $CD4^+$ T cells expressing CCR2 and CCR5. Expression of MCP-1 in the corneal stroma was confirmed in vivo. Finally, when HSV-1-primed $CD4^+$ T cells were adoptively transferred into wild type and MCP-1-deficient mice that had been sublethally irradiated to minimize chemokine production from immune cells, infiltration of $CD4^+$ T cells was markedly reduced in the MCP-1-deficient mice, suggesting that it is the MCP-1 from HSV-1-infected keratocytes that attracts $CD4^+$ T cells into the cornea.

• The Korean Journal of Vision Science
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• v.20 no.4
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• pp.561-568
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• 2018

Purpose : The size and regular array of the collagen fibers in the corneal stroma have very close correlation with transparency. Simulation was carried out to investigate the change of light transmittance according to the array structure and collagen fiber layer thickness. Methods : The collagen fibers in corneal stroma were arranged in regular hexagonal, hexagonal, square and random shapes with OptiFDTD simulation software, and the light transmittance was analyzed. In square array, the light transmittance according to the density change was confirmed by when the number of collagen fibers in the simulation space was the same and the light transmittance was examined when the number and density of collagen fibers were changed. Results : When the number of collagen fibers is the same, the density becomes smaller and the thickness of the fibrous layer becomes thicker in order of arrangement of square, regular hexagonal, random and hexagonal. As a result of measuring the light transmittance by changing the array structure, the light transmittance measured at the detector at the same position was almost similar regardless of the array structure. In the detectors D0, D1, D2 and D3, the maximum transmittance is shown in square, hexagonal and square, regular hexagonal and regular hexagonal array structure, and the minimum transmittance is hexagonal, random, hexagonal and square, and square array structure. However, the difference between the maximum transmittance and the minimum transmittance was almost the same within 1%. When the number of collagen fibers was the same, the light transmittance of the rectangular array structure decreased with increasing fiber layer thickness. And as the thickness increased, the light transmittance decreased more when the number of collagen fibers decreased. Conclusion : Even though the collagen array structure changed, the light transmittance is almost similar regardless of the arrangement structure. However, as the array structure was changed, the thickness of the collagen fiber layer changed, and as the thickness increased, the light transmittance decreased. In other words, the transparency of the corneal stroma is more closely related to the thickness of the fibrous layer than the array of collagen fibers.