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    A Flow Cytometric Study About the Immunopathology of Vernal Keratoconjunctivitis
    (1998) Avunduk, A. M.; Avunduk, M. C.; Dayanır, V.; Tekelioğlu, Y.; Dayıoğlu, Y. S.
    Background: Vernal keratoconjunctivitis (VKC) is a bilateral seasonal conjunctival inflammation. Exact pathogenesis of the disease is unknown, but some evidences suggest TH lymphocyte-mediated immune reactions. Objective: The aim of this study was to investigate the role of the T lymphocyte and its subsets in the pathogenesis of VKC. Methods: We obtained tear samples from patients with VKC and normal volunteers during active (spring) and quiescent (winter) periods. The patients' records were also obtained for assessment of symptom scores. The percentages of CD4/29+, CD4/45RA+, CD4+, and CD8+ in tear samples were established by using flow cytometry, and the results of all three groups were compared with each other by using the Wilcoxon matched-pair signed-rank test and the Mann-Whitney U test. Results: The percentages of CD4/29+ and CD4+ cells in tears of patients with VKC increased significantly in the active period and decreased to normal levels in the quiescent stage. In contrast, the percentages of CD4/45RA+ and CD8+ cells in tears of patients with VKC did not show any significant change between spring and winter. The patients' symptoms were significantly lower in the quiescent period (winter) compared with the active stage (spring). Conclusion: We propose that increased numbers of CD4+ and CD4/29+ cells in tears may be exacerbating the disease during the spring season.
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    Prevention of Lens Damage Associated with Cigarette Smoke Exposure in Rats by ?- Tocopherol (Vitamin E) Treatment
    (1999) Avunduk, A. M.; Yardımcı, S.; Avunduk, Mustafa Cihat; Kurnaz, L.; Aydın, A.; Koçkar, M. C.; Delibaşı, T.
    PURPOSE. To evaluate the possible protective effect and mechanism of ?- tocopherol (vitamin E) treatment on lens degeneration associated with in vivo exposure to cigarette smoke and to further clarify tile role of iron in cigarette smoke-generated lens damage. METHODS. Twenty-eight male Wistar rats were randomly divided into four equal groups. Rats in groups 3 and 4 were exposed to cigarette smoke for 1 hour each day over 90 consecutive days, and rats in groups 1 and 2 were treated in similar fashion but only exposed to room air. Additionally, vitamin E was given to the rats in groups 2 and 4 via intramuscular route. At the end of the study, both eyes of all the animals were enucleated; one eye was prepared for histopathologic examination, and the fellow eye was used for the measurement of iron and calcium levels. RESULTS. Significantly higher iron and calcium levels were observed in the lenses of group 3 rats than in other groups. Similar comparisons performed between groups 1 and 2, groups 1 and 4, and groups 2 and 4 did not show any significant difference. Distinct histopathologic changes in the anterior lens epithelium, such as hyperplasia, hypertrophy, epithelial multilayering, and the presence of epithelial cells over posterior lens capsule, observed in group 3 rats were not present in other groups. CONCLUSIONS. Cataractogenesis after cigarette smoke exposure was associated with an accumulation of iron and calcium in the rat lens, and vitamin E supplementation protected such accumulations and cataractogenesis.