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Purpose: Hazelnut and birch pollen are known to destroy tear film components and attack ocular surface cells. We investigated further pollen species from different plant families, whether they show similar effects on human tear fluid and an epithelial cell line in vitro, to provide a broad basis for further research on pollen reactions affecting the tear film and ocular surface. Materials and methods: Regional pollen species from different plant families (Adoxaceae, Betulaceae, Fagaceae, Juglandaceae, Malvaceae, Oleaceae, Pinaceae, Plantaginaceae, Poaceae, Salicaceae, Sapindaceae) were collected. Their proteolytic activity was evaluated by Zymography. Human tear fluid and cells of an epithelial cell line were incubated with pollen extracts. Tear fluid was analyzed by Polyacrylamide gel electrophoresis (PAGE). Cytomorphology was assessed microscopically and cell viability by proliferation (MTS), water-soluble tetrazolium (WST-1) assay and the impedance-based xCELLigence real-time analysis (RTCA). Results: Zymography revealed significant protease activity and PAGE showed the degradation of tear proteins by different pollen species. Cells incubated with pollen extracts presented dose- and time-dependent cytomorphological changes. MTS, WST-1, and RTCA revealed cytostatic as well as cytotoxic effects of pollen extracts. Conclusions: Pollen species from different plant families exert proteolytic activity and degrade human tear fluid as well as epithelial cells, which may play a crucial role in the pathogenesis of allergic and non-allergic reactions affecting the ocular surface. [ABSTRACT FROM AUTHOR]

Context: Contact with pollen is the major reason for the development of allergic symptoms on the ocular surface leading to a significant increase of allergic diseases worldwide. Environmental changes such as increased ultraviolet (UV) radiation and air pollution are discussed as contributory causes for this increase. Objective: We investigated the effect of UV light on the histamine content of pollen and examined if an irradiation of pollen affects the viability and proliferation of conjunctival cells. Materials and methods: Alder (Alnus glutinosa) and hazel (Corylus avellana) pollen were irradiated for different time periods with sunlight, UV-A or UV-B light and the histamine content was analysed and compared with non-irradiated pollen. Conjunctival epithelial cells (CHANG cells) were exposed to irradiated and non-irradiated pollen followed by an assessment of cell viability with the colorimetric MTS test and the impedance-based measurement of cell proliferation using the xCELLigence real-time analysis system. Results: UV light irradiation increased the histamine level of alder and hazel pollen in a dose-dependent manner. CHANG cells treated with irradiated pollen induced a statistically significant higher decrease of cell viability than treatment with non-irradiated pollen. Discussion and conclusions: Our results indicate that UV light is able to alter pollen thus making them more harmful for conjunctival cells. [ABSTRACT FROM AUTHOR]

. Purpose: To evaluate ocular surface characteristics and tear film function following modified Hughes flap for eyelid reconstruction. Methods: This is an institutional study including 18 patients (6 male, 12 female) who underwent a tarsoconjunctival flap for reconstructing the lower eyelid's posterior lamella in one eye between 2005 and 2010. The median age of the patients was 72 (49-93) years at the time of surgery and 77 (51-97) years at the time of evaluation. The median follow-up time was 34 (9-69) months. All patients had large malignant or semi-malignant lid tumours. Data for subjective symptoms (OSDI questionnaire), lid margin morphology, tear break-up time (BUT), vital staining, Schirmer test, impression cytology, tear film osmolarity, lipid layer interference patterns, meibography and the size of the tumour and flap were recorded and compared with the contralateral side. Results: Statistical analysis of the data revealed a significant difference between the surgically treated lid and the untreated side in meibomian gland loss, more lid margin abnormalities in the upper and lower eyelid (p < 0.001) and increased fluorescein staining of the cornea (p = 0.031). For the operated side, the median OSDI score was higher (17.2 versus 14.7), and the median BUT value was shorter (4.2 versus 5.6 seconds) compared with the median values of the contralateral side. Conclusion: Despite the favourable cosmetic and functional results of the Hughes tarsoconjunctival flap, our results indicate that this procedure does affect the ocular surface health in the treated eyes. [ABSTRACT FROM AUTHOR]

Purpose of the study: Retinal vein occlusion (RVO) is a major vision-threatening disease. Vitamin K epoxide reductase recycles reduced vitamin K, which is essential for the gamma carboxylation of clotting factors II, VII, IX, X and proteins C and S. Recently, the vitamin K epoxide reductase complex subunit 1 (VKORC1) --1639G>A (rs9923231) polymorphism has been reported as a novel risk factor for RVO in a Turkish population. The present study was set to confirm or to refute this association in a larger cohort of patients with RVO. Materials and methods: The present case-control study comprised 285 patients with central RVO, 401 patients with branch RVO and 333 control subjects. Genotypes of the VKORC1 -1639G>A polymorphism were determined by 5' exonuclease assay (TaqMan). Results: No significant differences in either genotype distributions or allele frequencies of the vitamin K epoxide reductase complex subunit 1 --1639G>A polymorphism were found between patients and control subjects (p>0.05). In a logistic regression analysis neither branch nor central RVO was predicted by the vitamin K epoxide reductase complex subunit 1 --1639G>A genotypes, but by arterial hypertension, ever-smoking status and in case of central RVO additionally by diabetes mellitus. Conclusions: Our data suggest that the vitamin K epoxide reductase complex subunit 1 --1639G>A gene polymorphism is unlikely a major risk factor for patients with either central or branch RVO. [ABSTRACT FROM AUTHOR]

Purpose of the Study: Retinal vein occlusion (RVO) is a major vision-threatening disease. Vitamin K epoxide reductase recycles reduced vitamin K, which is essential for the gamma carboxylation of clotting factors II, VII, IX, X and proteins C and S. Recently, the vitamin K epoxide reductase complex subunit 1 (VKORC1) -1639G>A (rs9923231) polymorphism has been reported as a novel risk factor for RVO in a Turkish population. The present study was set to confirm or to refute this association in a larger cohort of patients with RVO., Materials and Methods: The present case-control study comprised 285 patients with central RVO, 401 patients with branch RVO and 333 control subjects. Genotypes of the VKORC1 -1639G>A polymorphism were determined by 5' exonuclease assay (TaqMan)., Results: No significant differences in either genotype distributions or allele frequencies of the vitamin K epoxide reductase complex subunit 1 -1639G>A polymorphism were found between patients and control subjects (p > 0.05). In a logistic regression analysis neither branch nor central RVO was predicted by the vitamin K epoxide reductase complex subunit 1 -1639G>A genotypes, but by arterial hypertension, ever-smoking status and in case of central RVO additionally by diabetes mellitus., Conclusions: Our data suggest that the vitamin K epoxide reductase complex subunit 1 -1639G>A gene polymorphism is unlikely a major risk factor for patients with either central or branch RVO.