bromochloroacetic-acid and Eye-Injuries

Topics: Animals; Basement Membrane; Cattle; Chemical Phenomena; Chemistry; Chondroitin; Choroid; Collagen; Connective Tissue; Cornea; Elastic Tissue; Electrophoresis, Disc; Eye; Eye Injuries; Galactose; Glucose; Glycine; Glycosaminoglycans; Hyaluronic Acid; Hydroxyproline; Keratins; Lens, Crystalline; Peptides; Proline; Rabbits; Sclera; Vertebrates; Vitreous Body

PAX6 heterozygosity (PAX6(+/-)) causes aniridia and aniridia-related keratopathy (ARK) in humans, but the pathway from gene dosage deficiency to clinical disease has not been fully characterized. Recently, the authors suggested a model of a chronic wound state exacerbated by oxidative stress, showed the barrier function of Pax6(+/-) corneas is compromised and suggested Pax6(+/-) corneas show the molecular signature of a perpetual wound-healing state.. Pax6(+/-) mice were used as a model for Pax6-related corneal diseases and in vivo wound-healing assays. Immunohistochemistry and electron microscopy analyses were performed on mutant and wounded corneas.. This work reports defects in keratin, desmoplakin, and actin-based cytoskeletal structures in Pax6(+/-) cells. During wild-type corneal reepithelialization, cell fissures and desquamation, intracellular vesicles, intercellular gaps, and filopodialike structures were apparent, similar to the phenotypes seen in "unwounded" Pax6(+/-) corneal epithelia. Pax6(+/-) cells and wounded wild-type cells showed changed patterns of desmoplakin and actin localization. Protein oxidation and ERK1/2 and p38 MAPK phosphorylation were barely detected in the basal cells of intact wild-type corneal epithelia, but they were found in basal wild-type cells near the wound edge and throughout Pax6(+/-) corneal epithelia.. These data show that cell junctions and cytoskeleton organization are dynamically remodeled in vivo by wounding and in Pax6(+/-) corneas. This apparent wound-healing phenotype contributes to the clinical aspects of ARK.

Topics: Actins; Animals; Aniridia; Cell Adhesion; Cells, Cultured; Corneal Diseases; Cytoskeletal Proteins; Desmoplakins; Epithelium, Corneal; Eye Injuries; Eye Proteins; Female; Homeodomain Proteins; Keratins; Male; Mice; Mice, Inbred CBA; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Mitogen-Activated Protein Kinase 3; Mitogen-Activated Protein Kinase 6; p38 Mitogen-Activated Protein Kinases; Paired Box Transcription Factors; PAX6 Transcription Factor; Phosphorylation; Repressor Proteins

Diffuse and cystic epithelial downgrowth occur rarely, but they represent a mostly preventable potential cause of blindness as sequels to trauma and surgery. The aim of this study is to report on the etiology and course of disease in patients with histologically verified epithelial downgrowth.. From 1986 until 2000 the ophthalmopathological laboratory of the University Eye Hospital Hamburg-Eppendorf received 13 (4 external) referrals. Ten patients with cystic of diffuse intraocular epithelial downgrowth were treated and 9 eyes were operated on in the Hospital.. At presentation 4/10 patients had a visual acuity of < or = 0.1, and 2/10 had no light perception. A cystic epithelial downgrowth was verified histologically in 9/13, and a diffuse form in 4/13 patients. Mucin production was proven histochemically in 1/9 intraocular epithelial downgrowth sections. In one case a spontaneous iris cyst was detected by the immunohistological examinations. Trauma (10/14) and surgery (3/14) were the most frequent causes and were symptomatic on average 17 years after the primary event. A curative surgery was done in 13/14 patients (5 x en bloc excision, 2 x penetrating keratoplasty, 1 x iridectomy, 2 x enucleations, 3 x external) resulting in no recurrences during the follow-up of 4(1/2) years (1 - 12 years). The postoperative visual acuity was ameliorated in 5/9, worsened in 2 patients, and 2 were enucleated.. Epithelial downgrowth is a rare but preventable cause of blindness. The most important prophylaxis is meticulous primary surgery including a sufficient wound closure. The visual outcome depends on the preoperative conditions.

Topics: Adolescent; Adult; Aged; Blindness; Cell Division; Child; Choristoma; Ciliary Body; Conjunctiva; Cysts; Epithelium; Epithelium, Corneal; Eye; Eye Diseases; Eye Enucleation; Eye Injuries; Female; Humans; Keratins; Male; Middle Aged; Postoperative Complications; Reoperation; Visual Acuity

To determine the feasibility of using human amniotic membrane (AM) as a substrate for culturing oral epithelial cells and to investigate the possibility of using autologous cultivated oral epithelial cells in ocular surface reconstruction.. An ocular surface injury was created in one eye of each of eight adult albino rabbits by a lamellar keratectomy, and a conjunctival excision was performed, including and extending 5 mm outside the limbus. Oral mucosal biopsy specimens were obtained from these eight adult albino rabbits and cultivated for 3 weeks on a denuded AM carrier. The cultivated epithelium was examined by electron microscopy (EM) and immunohistochemically labeled for several keratins. At 3 to 4 weeks after the ocular surface injury, the conjunctivalized corneal surfaces of the eight rabbits were surgically reconstructed by transplanting the autologous cultivated oral epithelial cells on the AM carrier.. The cultivated oral epithelial sheet had four to five layers of stratified, well-differentiated cells. EM revealed that the epithelial cells were very similar in appearance to those of normal corneal epithelium, had numerous desmosomal junctions, and were attached to a basement membrane with hemidesmosomes. Immunohistochemistry confirmed the presence of the keratin pair 4 and 13 and keratin-3 in the cultivated oral epithelial cells. Corneas that were grafted with the cultivated oral epithelial cells on an AM carrier were clear and were all epithelialized 10 days after surgery.. Cultures of oral epithelial cells can be generated to confluence on AM expanded ex vivo from biopsy-derived oral mucosal tissue. Autologous transplantation was performed with these cultivated oral epithelial cells onto the ocular surfaces of keratectomized rabbit eyes. Autologous transplantation of cultivated oral epithelium is a feasible method for ocular surface reconstruction. The long-term outcome of such transplantation is not yet clear, and its feasibility in clinical use should be evaluated further.

Topics: Amnion; Animals; Cell Culture Techniques; Cell Division; Corneal Injuries; Disease Models, Animal; Epithelial Cells; Eye Injuries; Feasibility Studies; Fluorescent Antibody Technique, Indirect; Humans; Keratins; Mouth Mucosa; Rabbits; Transplantation, Autologous

Keratocytes synthesize keratan-sulfate proteoglycans (KSPG), lumican and keratocan, to develop and maintain proper collagen interfibrillar spacing and fibril diameter characteristics of the transparent cornea. The purposes of this study are to compare the expression patterns of KSPGs and keratin 12 (K12) respectively by corneal keratocytes and epithelial cells after three different types of injuries; partial and total epithelial debridement and alkali burn.. Corneas of 8-12 week old C57Bl/6J or FVBN mice were wounded by partial epithelial (2 mm in diameter) and total epithelial debridement, and alkali burn (0.1 M NaOH, 30 s) and were allowed to heal for various periods of time, from 1 to 84 days. The corneas were then subjected to light microscopy, in situ and Northern hybridization and RT-PCR for examining the expression of K12 and KSPG in the corneal epithelium and stroma, respectively. Immunohistochemistry with anti-alpha-smooth muscle actin (alpha-SMA) was used to identify myofibroblasts in the stroma of injured cornea.. In 2-3 days, partial epithelial denuded corneas were resurfaced by corneal epithelium positive for K12, and stromal edema caused by debridement disappeared. Total epithelial debridement wounded corneas were resurfaced by conjunctival epithelial cells in 2 weeks. Stromal edema in the total epithelial debridement corneas began to subside after 6 weeks. Corneal epithelial cells resurfaced alkali burned corneas within 3-5 days. In situ and Northern hybridization showed a decrease in keratocan and lumican expression at 6 weeks and increased at 12 weeks post-injury in all wound types. Alpha-SMA positive myofibroblasts in the cornea were detected via immunostaining at the time point when KSPG expression was lowest, 6 weeks post-injury.. The results suggest keratocan and lumican are down-regulated during wound healing at 6 weeks and returned to higher levels at 12 weeks post-injury; implicating that the cells repopulating the injured corneal stroma regained the characteristic function of keratocytes independent of the wound types. However, complete epithelial removal results in irreversible loss of K12 expression.

Topics: Animals; Blotting, Northern; Burns, Chemical; Chondroitin Sulfate Proteoglycans; Cornea; Corneal Injuries; Corneal Stroma; Down-Regulation; Epithelium, Corneal; Eye Burns; Eye Injuries; Eye Proteins; Fibroblasts; Immunoenzyme Techniques; In Situ Hybridization; Keratan Sulfate; Keratin-12; Keratins; Lumican; Mice; Mice, Inbred C57BL; Proteoglycans; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sodium Hydroxide; Wound Healing

To investigate the possibility of using cultivated oral epithelial cells in ocular surface reconstruction.. An ocular surface injury was created in adult albino rabbits by a lamellar keratectomy. Oral mucosal biopsy specimens taken from both adult albino rabbits and human volunteers were cultivated for 2-3 weeks on a denuded amniotic membrane (AM) carrier. The cultivated epithelium was examined by histologic and immunohistochemical analysis. At 3-4 weeks after the ocular surface injury, the rabbit conjunctivalized corneal surfaces were surgically reconstructed by transplanting both the rabbit and human cultivated oral epithelial cells on the AM carrier.. Both the rabbit and human cultivated oral epithelial sheets had 5 or 6 layers of stratified, well-differentiated cells. Histologic examination revealed that the cultivated epithelial cells were similar in appearance to those of in vivo normal corneal epithelium. Immunohistochemistry confirmed the presence of the keratin pair 4 and 13 and keratin 3 in the cultivated oral epithelial cells. Corneas that were grafted with rabbit and human cultivated oral epithelial cells on an AM carrier were clear and were epithelialized 10 and 2 days after surgery, respectively.. We have generated confluent cultures of both rabbit and human oral epithelial cells on AM expanded ex vivo from biopsy-derived oral mucosal tissues. We have successfully carried out xeno- and autologous transplantation of these cultivated oral epithelial cells onto the ocular surfaces of keratectomized rabbit eyes. We believe that xeno- and autologous transplantation of cultivated oral epithelium is a feasible method for ocular surface reconstruction.

Topics: Animals; Cells, Cultured; Eye Injuries; Humans; Immunohistochemistry; Keratins; Mouth Mucosa; Ophthalmologic Surgical Procedures; Plastic Surgery Procedures; Rabbits; Stem Cell Transplantation; Transplantation, Autologous; Transplantation, Heterologous

1. The aim of this study was to determine the epithelial changes of the conjunctiva and cornea up to 7 days after corneal debridement and the changes highlighted included (1) proliferation, (2) production of growth factor, (3) changes in calcium binding protein marker, (4) production of cytokine, and (5) maturity of the regeneration corneal epithelium. 2. The cytochemical changes of the corneal and conjunctival epithelia of rabbit were analyzed up to 7 days after debridement. 3. An increase in proliferating cell nuclear antigen (PCNA) was observed in the limbal epithelia 12 hr after lesion and reached a peak by 48 hr. 4. Some proliferating limbal cells also contained epidermal growth factor (EGF) beginning 24 hr after injury. The early limbal cell proliferation and the EGF production and their persistence until 7 days after lesion were likely involved with the process of regeneration. 5. Other positive markers appeared after lesion included tumor necrosis factor (TNFalpha) and calcium binding proteins S100A and S100B, which appeared mainly within the first 48 hr after lesion and then started to decline. The short appearance and the relatively small quantity of TNFalpha indicated that this cytokine was probably not very important in the repair process and its appearance might be related to the injury induced. The presence of S100A and S100B could be associated with both cell death after injury and the proliferation of new epithelium. 6. The cornea epithelium was still immature 7 days after lesion in that it still contained cytokeratin. 7. In conclusion, the critical hours of peak conjunctival and corneal changes after corneal debridement were in the first 2 days.

Topics: Animals; Biomarkers; Calcium-Binding Proteins; Conjunctiva; Debridement; Epidermal Growth Factor; Epithelium, Corneal; Eye Injuries; Histocytochemistry; Keratins; Nerve Growth Factors; Proliferating Cell Nuclear Antigen; Rabbits; S100 Calcium Binding Protein beta Subunit; S100 Proteins; Time Factors; Tumor Necrosis Factor-alpha