In this article, we provide the results of experimental studies demonstrating that corneal avascularity is an active process involving the production of anti-angiogenic factors, which counterbalance the proangiogenic/lymphangiogenic factors that are upregulated during wound healing. We also summarize pertinent published reports regarding corneal neovascularization (NV), corneal lymphangiogenesis and corneal angiogenic/lymphangiogenic privilege. We outline the clinical causes of corneal NV, and discuss the angiogenic proteins (VEGF and bFGF) and angiogenesis regulatory proteins. We also describe the role of matrix metalloproteinases MMP-2, -7, and MT1-MMP, anti-angiogenic factors, and lymphangiogenic regulatory proteins during corneal wound healing. Established and potential new therapies for the treatment of corneal neovascularization are also discussed.

Although difficult to obtain, useful functional recovery can be achieved with proper surgical management of ulnar nerve entrapments and injuries.

Capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide), a natural product of Capsicum species, is known to induce excitation of nociceptive terminals involved in pain perception. Recent studies have also shown that capsaicin not only has chemopreventive properties against certain carcinogens and mutagens but also exerts anticancer activity. Here, we demonstrated the antiangiogenic activity of capsaicin using in vitro and in vivo assay systems. In vitro, capsaicin inhibited vascular endothelial growth factor (VEGF) -induced proliferation, DNA synthesis, chemotactic motility, and capillary-like tube formation of primary cultured human endothelial cells. Capsaicin inhibited both VEGF-induced vessel sprouting in rat aortic ring assay and VEGF-induced vessel formation in the mouse Matrigel plug assay. Moreover, capsaicin was able to suppress tumorinduced angiogenesis in chick chorioallantoic membrane assay. Capsaicin caused G 1 arrest in endothelial cells. This effect correlated with the down-regulation of the expression of cyclin D1 that led to inhibition of cyclin-dependent kinase 4-mediated phosphorylation of retinoblastoma protein. Signaling experiments show that capsaicin inhibits VEGFinduced p38 mitogen-activated protein kinase, p125 FAK , and AKT activation, but its molecular target is distinct from the VEGF receptor KDR/ Flk-1. Taken together, these results demonstrate that capsaicin is a novel inhibitor of angiogenesis and suggest that it may be valuable to develop pharmaceutical drugs for treatment of angiogenesis-dependent human diseases such as tumors.

Specific factors from the corneal epithelium underlying the stimulation of stromal fibrosis and myofibroblast formation in corneal wound healing have not been fully elucidated. Given that exosomes are known to transfer bioactive molecules among cells and play crucial roles in wound healing, angiogenesis, and cancer, we hypothesized that corneal epithelial cell-derived exosomes may gain access to the underlying stromal fibroblasts upon disruption of the epithelial basement membrane and that they induce signaling events essential for corneal wound healing. In the present study, exosome-like vesicles were observed between corneal epithelial cells and the stroma during wound healing after corneal epithelial debridement. These vesicles were also found in the stroma following anterior stromal keratectomy, in which surgical removal of the epithelium, basement membrane, and anterior stroma was performed. Exosomes secreted by mouse corneal epithelial cells were found to fuse to keratocytes in vitro and to induce myofibroblast transformation. In addition, epithelial cell-derived exosomes induced endothelial cell proliferation and ex vivo aortic ring sprouting. Our results indicate that epithelial cell-derived exosomes mediate communication between corneal epithelial cells and corneal keratocytes as well as vascular endothelial cells. These findings demonstrate that epithelial-derived exosomes may be involved in corneal wound healing and neovascularization, and thus, may serve as targets for potential therapeutic interventions.

This work presents the results of numerical simulation and experimental visualization of the mold filling process in resin injection molding with preplaced fiber mats. The mold filling experiments were conducted with various mat stacks consisting of continuous random glass fiber mats and bidirectional stitched glass fiber mats. The use of two different mat types in the mat stack created porosity and permeability variations. The effect of these permeability variations was studied by taking flow pressure measurements and observing the progress of the flow front of a non-reactive fluid filling a clear acrylic mold that contained the reinforcement mat stack. Numerical simulation corresponding to each experiment was also carried out. The numerical results were compared to the experimental measurements.

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Background/Aims: Decorin has been shown to have antiangiogenic properties. In this study, we evaluate the involvement of membrane type 1-matrix metalloproteinase (MT1-MMP), a proangiogenic enzyme, in decorin cleavage in the cornea. Methods: MT1-MMP expression was confirmed immunohistochemically in keratocytes and immortalized corneal fibroblast cell lines. Corneal micropockets of bFGF were used to assess the expression of decorin and MT1-MMP. Western blotting was used to evaluate decorin degradation by MT1-MMP. Aortic ring tube formation assays were used to assay the inhibitory effect of decorin and stimulatory effect of MT1-MMP on vascular endothelial cells in vitro. Results: We show that MT1-MMP expression is upregulated following bFGF pellet implantation in the cornea in vivo, and that MT1-MMP cleaves decorin in a time- and concentration-dependent manner in vitro. Furthermore, the addition of MT1-MMP reduces the inhibitory effects of decorin on aortic ring tube formation in vitro. Cleavage of decorin by MT1-MMP-deficient corneal cell lysates is diminished relative to that by wild-type corneal cell lysates, and an MT1-MMP knockin restores decorin processing in vitro. Conclusion: The proangiogenic role of MT1-MMP in the cornea may be mediated, in part, by facilitated cleavage of corneal decorin.

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