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The study aimed to directly assess the ocular safety of 222-nm far-ultraviolet-C (UVC) irradiation in humans, given the limited clinical trials in this area. This wavelength offers the potential for safe and effective microbial inactivation in occupied spaces, but its safety profile for human eyes requires thorough investigation. This prospective, interventional study involved five subjects aged 29-47 years, who were exposed to 222-nm UVC at doses of 22, 50, and 75 mJ/cm 2 . The subjects were monitored using custom-made glasses with a UV-cut filter on one eye to serve as a control. UVC irradiation was conducted using a KrCl excimer lamp, and ocular examinations were performed prior to exposure, 24 h post-exposure, and at 1, 3, and 6 months. Parameters assessed included visual acuity, refractive error, corneal endothelial density, corneal erosion scores, and conjunctival hyperemia scores. The study found no clinically significant photokeratitis or long-term eye damage across the five subjects, even at the highest dose of 75 mJ/cm 2 . Temporary ocular discomfort, including sensations of dryness and epiphora, was reported, but these symptoms subsided within hours after irradiation. The findings indicate that 222-nm far-UVC irradiation up to 75 mJ/cm 2 does not cause "clinically significant photokeratitis" or long-term ocular damage, though it may induce temporary discomfort. This supports the safe use of 222-nm UVC for germicidal applications in occupied environments, providing a basis for revised safety guidelines., (© 2024 The Author(s). Photochemistry and Photobiology published by Wiley Periodicals LLC on behalf of American Society for Photobiology.)

Recent studies have highlighted the indispensable role of oxidized lipids in inflammatory responses, cell death, and disease pathogenesis. Consequently, inhibitors targeting oxidized lipids, particularly lipid-derived radicals critical in lipid peroxidation, which are known as radical-trapping antioxidants (RTAs), have been actively pursued. We focused our investigation on nitroxide compounds that have rapid second-order reaction rate constants for reaction with lipid-derived radicals. A novel screening system was developed by employing competitive reactions between library compounds and a newly developed profluorescence nitroxide probe with lipid-derived radicals to identify RTA compounds. A PubMed search of the top hit compounds revealed their wide application as repositioned drugs. Notably, the inhibitory efficacy of methyldopa, selected from these compounds, against retinal damage and bilateral common carotid artery stenosis was confirmed in animal models. These findings underscore the efficacy of our screening system and suggest that it is an effective approach for the discovery of RTA compounds., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ken-ichi Yamada reports a relationship with FELIQS Corporation that includes: board membership, equity or stocks, and non-financial support. Ken-ichi Yamada holds patents for the screening system and for some of the compounds described herein. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

To evaluate the effectiveness of the PRESERFLO MicroShunt (PFM) in reducing intraocular pressure (IOP) ex vivo in porcine eyes using an infusion pump system and to simulate various IOP conditions, In this study, porcine eyes received increasing flows between 2 and 20 μL/min. IOP measurements were taken under conditions with and without the PFM [PFM (+) and PFM (-), respectively]. In the PFM (-) group, IOP increased from 7.4 mmHg to 46.3 mmHg as the flow rate increased from 2 μL/min to 20 μL/min. The rate of IOP reduction (%ΔIOP) rose with increasing flow rates, although the absolute IOP values achieved with the PFM insertion also increased. The correlation between IOPs in the PFM (-) conditions and the %ΔIOP was modeled as %ΔIOP = 22.4 Ln [PFM(-) IOP] - 41.7. According to this equation, IOP reduction by PFM insertion is 0% at IOPs of 6.4 mmHg or lower. IOP reductions of 10%, 20%, 30%, and 40% were observed when the pre-insertion IOPs were 10.1, 15.7, 24.6, and 38.4 mmHg, respectively. Achievable post-insertion IOP levels of ≤21 mmHg, ≤18 mmHg, ≤15 mmHg, and ≤12 mmHg corresponded to the initial IOPs of 33 mmHg, 26 mmHg, 20 mmHg, and 14.8 mmHg, respectively. In conclusion, the PFM effectively reduced IOP within a specific range of IOP values in an ex vivo experimental system. In clinical situations, the PFM is unlikely to be effective at low IOP levels. At higher levels, the PFM reduces IOP, but it may be insufficient to achieve the target IOP.

The COVID-19 pandemic underscored the crucial importance of enhanced indoor air quality control measures to mitigate the spread of respiratory pathogens. Far-UVC is a type of germicidal ultraviolet technology, with wavelengths between 200 and 235 nm, that has emerged as a highly promising approach for indoor air disinfection. Due to its enhanced safety compared to conventional 254 nm upper-room germicidal systems, far-UVC allows for whole-room direct exposure of occupied spaces, potentially offering greater efficacy, since the total room air is constantly treated. While current evidence supports using far-UVC systems within existing guidelines, understanding the upper safety limit is critical to maximizing its effectiveness, particularly for the acute phase of a pandemic or epidemic when greater protection may be needed. This review article summarizes the substantial present knowledge on far-UVC safety regarding skin and eye exposure and highlights research priorities to discern the maximum exposure levels that avoid adverse effects. We advocate for comprehensive safety studies that explore potential mechanisms of harm, generate action spectra for crucial biological effects and conduct high-dose, long-term exposure trials. Such rigorous scientific investigation will be key to determining safe and effective levels for far-UVC deployment in indoor environments, contributing significantly to future pandemic preparedness and response., (© 2023 American Society for Photobiology.)

Purpose: This study aimed to histologically compare the status of Schlemm's canal (SC) and Schlemm's canal endothelial (SCE) cells between trabeculectomy specimens from patients with primary open-angle glaucoma (POAG) and exfoliation glaucoma (EXG)., Methods: A total of 182 eyes from 152 patients with POAG and 138 eyes from 116 patients with EXG underwent immunohistochemical staining for thrombomodulin. Equal numbers of cases were selected from both groups using propensity score matching. The following parameters were evaluated: total SC length, staining positive and negative SC length (PSC and NSC, respectively), opened and closed SC length, staining positive and opened SC length, staining positive and closed SC length, staining negative and opened SC length (NOSC), and staining negative and closed SC length., Results: After matching for age and gender, 87 cases were selected in each group. The EXG group had significantly higher preoperative IOP and medication scores. PSC was significantly longer in the POAG group, while NSC and NOSC were longer in the EXG group. Multiple regression analysis of these 174 cases revealed that PSC was significantly shorter in the EXG group. After matching for age, gender, preoperative IOP, and medication score, 64 cases were selected in each group, and NOSC was significantly longer in the EXG group., Conclusions: These findings suggest that in EXG, SCE loss occurs independently of background factors such as aging and medication use. The loss of SCE may have a more critical impact on IOP elevation in EXG compared to POAG.

This study aims to investigate the pressure characteristics of the PRESERFLO MicroShunt, a microinvasive glaucoma device, using an in vitro setup. Additionally, the study explores the impact of the scleral tissue surrounding the device on its pressure and lumen area. Ten PRESERFLO MicroShunts were subjected to an in vitro experimental setup. A constant flow of physiological saline was maintained at 2 μL/min using an infusion syringe pump. The PRESERFLO was connected to a pressure transducer via a 23 G needle. Pressure characteristics were measured under three different conditions: without sclera [sclera (-)], passing through sclera at a 90° angle (sclera 90°), and passing through sclera at a 30° angle (sclera 30°). The lumen area of the device was measured using microscopic observation. We observed peak and trough pressures in this experimental setting; the peak pressure (6.76 mmHg) was significantly higher than the trough pressure of 4.74 mmHg ( p = 0.0020) in the sclera (-) condition. Compared to sclera (-), the peak pressures were significantly higher in the sclera 90° (7.81 mmHg, p = 0.0020) and the sclera 30° (7.96 mmHg, p = 0.0039) conditions. Additionally, compared to sclera (-), the trough pressure was significantly higher in the sclera 90° (6.25 mmHg, p = 0.0039) and the sclera 30° (5.76 mmHg, p = 0.037) conditions. The lumen area was significantly smaller in the sclera 90° condition (3515 μm 2 ) than the sclera (-) condition (3927 μm 2 , p = 0.0078). The study found that when the distal end of PRESERFLO MicroShunt was free and in air, it exhibited both peak and trough pressures. The presence of scleral tissue surrounding the PRESERFLO MicroShunt affects its lumen area and pressure characteristics. Understanding these effects can provide valuable insights into the device's performance.

Basal cells in the corneal limbus play an important role in the turnover cycle because they are the source of all cells that constitute the corneal epithelium. We examined the penetration depth of ultraviolet (UV) light in the corneal limbus and assessed the safety of Far-UV-C on stem cells in the basal area of the corneal limbus. Rats were irradiated with UV at peaks of 207, 222, 235, 254 and 311 nm while under anesthesia. The UV penetration depth in the rat corneal limbal epithelium was wavelength dependent: 311 nm UV-B and 254 nm UV-C reached the basal cells of the epithelium, and 235 nm radiation reached the middle area; however, 207 and 222 nm UV-C reached only the superficial layer of the epithelium. Porcine cornea, which is similar to the human eye in size and structure, were irradiated with 222 and 254 nm UV-C. As in rats, 222 nm UV-C reached only the superficial layer of the porcine corneal limbal epithelium. These results indicate that Far-UV-C, such as radiation of wavelengths of 207 and 222 nm, could not reach corneal epithelial stem cells, i.e. the cells remained intact. It is unlikely that the turnover of the corneal epithelium is obstructed or disrupted by exposure to Far-UV-C., (© 2022 The Authors. Photochemistry and Photobiology published by Wiley Periodicals LLC on behalf of American Society for Photobiology.)

Background: We report a case with two connected stents ejected simultaneously during an iStent inject W surgery, a modified second-generation iStent Trabecular Micro-Bypass System., Case Presentation: A 57-year-old woman with primary open-angle glaucoma underwent a combined cataract and iStent inject W surgery in her left eye. After the trabecular meshwork/Schlemm's canal was pierced by the trocar of injector, the delivery button was pressed a first time, but the stent was not ejected. After the button was pressed a second time, connected two stents were ejected. After removing the dislocated stents from the anterior chamber, two stents were implanted into the desired places using another injector. Except for mild hyphema, no postoperative complication occurred. Stereomicroscopic observation showed that the two stents were connected by a broken trocar shaft. An X-ray showed that the trocar shaft was broken at the part referred to as the "sprayed trocar". Scanning electron microscopy showed that the surface features of the broken trocar and trocar tip represented tensile failure., Conclusions: Although rare, considering that the damage was seen at the structurally weak part (i.e., sprayed trocar), the same phenomenon can happen. For patient safety, surgeons are recommended to inspect the device when the deployment of either the first or second stent is unsuccessful during the iStent inject surgery., (© 2023. The Author(s).)

Two krypton-chloride germicidal excimer lamp units (Care222 TRT-104C11-UI-U3, USHIO Inc.) were installed in the examination room of an ophthalmology department. The irradiation dose was set not to exceed the former (i.e., before 2022) threshold limit value (TLV) (22 mJ cm -2 /8 h) recommended by the ACGIH. Section 1: The eyes and lids of the six ophthalmologists (5 wore glasses for myopic correction) who worked in the room for a mean stay of 6.7 h week -1 were prospectively observed for 12 months. Slitlamp examinations revealed neither acute adverse events such as corneal erosion, conjunctival hyperemia, and lid skin erythema nor chronic adverse events such as pterygium, cataract, or lid tumor. The visual acuity, refractive error, and corneal endothelial cell density remained unchanged during the study. Section 2: The irradiation of samples placed on the table or floor using the same fixtures in the room (5-7.5 mJ cm -2 ) was associated with >99% inhibition of φX174 phage and >90% inhibition of Staphylococcus aureus. In conclusion, no acute or chronic health effects in human participants was observed in a clinical setting of full-room ultraviolet germicidal irradiation by 222-nm lamp units, and high efficacy in deactivation of microorganisms was determined in the same setting., (© 2022 The Authors. Photochemistry and Photobiology published by Wiley Periodicals LLC on behalf of American Society for Photobiology.)

Purpose: The purpose of this study was to assess the pressure characteristics of the Ahmed Glaucoma Valve (AGV) and possible effects of air trapped in the tube., Method: Physiologic saline was pumped through 17 AGVs using a syringe infusion pump, and the flow pressure was measured by a set of pressure transducers. During the infusion at a rate of 2 µL/minute, the pressure measurement was repeated twice in each AGV to determine the repriming pressures with/without air (1 µL) in the tube., Results: After a pressure surge occurred during the initial priming, the pressure decreased suddenly and then became constant. The repriming pressure, determined as the peak pressure before valve opening, was significantly (P < 0.0001, paired t-test) higher with air (26.5 ± 6.8 mm Hg) than without air (12.1 ± 3.8 mm Hg), whereas the constant pressures after repriming was equivalent between with (10.6 ± 3.7 mm Hg) and without (10.4 ± 2.9 mm Hg) air conditions (P = 0.68)., Conclusions: Air in the AGV tube causes increased repriming pressure of about two-fold compared to repriming without air. This pressure increment caused by air in the capillary-sized tube might occur because of the effects of viscosity pressure and capillary pressure., Translational Relevance: To ensure stable surgical results, surgeons are advised to not allow air to remain in the tube. Pars plana tube insertion of the AGV combined with gas tamponade surgery may result in higher-than-expected intraocular pressure. Conversely, injection of air/gas can avoid postoperative hypotony when the AGV is implanted in eyes with a high risk of hypotony.

We comprehensively assessed the roles of systemic redox markers by including both prooxidant and antioxidant markers in 121 Japanese subjects (mean ± SD age, 70 ± 11 years; 38 men) with no ocular pathology except age-related cataract. Serum levels of lipid peroxides, ferric-reducing activity, and thiol antioxidant activity were measured using the diacron reactive oxygen metabolite (dROM), biologic antioxidant potential (BAP), and sulfhydryl (SH) tests, respectively, using a free-radical analyzer. Univariate analyses suggested that older age, higher pulse rate, worse best-corrected visual acuity (BCVA), higher intraocular pressure, and higher cataract grade were associated with a lower SH level. Scatterplots revealed virtually linear associations between age and the SH level (estimate, -4.4 μM/year). Multivariate analyses suggested that older age, higher systolic blood pressure, and worse BCVA were associated with a lower SH level. Neither the univariate nor multivariate analyses, except between female sex and higher dROM level, were associated with the dROM or BAP level. A lower serum SH level was the driver of aging itself and age-related decline in VA due to cataract. The serum SH level may be an excellent predictor of aging status in each subject., Competing Interests: No potential conflicts of interest were disclosed., (Copyright © 2023 JCBN.)

We previously proposed the total assessment of hydroxylinoleates (HODEs) by LC-MS/MS after saponification and reduction of the biologic samples as biomarkers to investigate pathogenesis, disease progression, and prognosis. In this study, HODE levels were estimated in aqueous humor (AH) samples from 63 eyes (41 Japanese subjects; 15 men; mean age, 77.3 ± 6.8 years) with primary open-angle glaucoma (POAG) or cataracts. The correlations between intraocular HODE levels and background parameters, including intraocular pressure (IOP), were analyzed to assess the possible involvement of oxidative stress in glaucoma pathology. Univariate analyses showed that linoleic acid (LA) ( p = 0.034) and arachidonic acid (AA) ( p = 0.0041) levels were associated negatively with age; 13-(Z,E)-HODE ( p = 0.018) and 13-(E,E)-HODE ( p = 0.021) were associated positively with IOP; 9-(Z,E)-HODE ( p = 0.039), 13-(Z,E)-HODE ( p = 0.021), totally assessed-HODE (t-HODE, p = 0.023), LA ( p = 0.0080), and AA ( p = 0.0051) were higher in eyes with glaucoma than cataract. No gender differences were seen. A mixed-effect regression model showed that higher 13-(Z,E)-HODE ( p = 0.0040) and higher t-HODE ( p = 0.040) were associated with glaucoma rather than cataracts; and higher levels of 13-(Z,E)-HODE/LA ( p = 0.043), 13-(E,E)-HODE/LA ( p = 0.042), 13-(Z,E)-HODE ( p = 0.0054), and 13-(E,E)-HODE ( p = 0.027) were associated with higher IOP. Linoleate-derived oxidation products were quantified successfully in AH samples from patients with glaucoma and cataracts. A free radical oxidation mechanism can be associated with IOP elevation, while enzymatic oxidation may be involved, specifically, in the pathogenesis of POAG.

The effects of visible light, from short to long wavelengths, on the retina were investigated functionally and histologically. The left eyes of Sprague-Dawley albino rats (6-weeks old, n = 6 for each wavelength) were exposed to seven narrow-band wavelengths (central wavelengths, 421, 441, 459, 501, 541, 581, and 615 nm) with bandwidths of 16 to 29 nm (half bandwidth, ±8-14.5 nm) using a xenon lamp source with bandpass filters at the retinal radiant exposures of 340 and 680 J/cm 2 . The right unexposed eyes served as controls. Seven days after exposure, flash electroretinograms (ERGs) were recorded, and the outer nuclear layer (ONL) thickness was measured. Compared to the unexposed eyes, significant reductions in the a- and b-wave ERG amplitudes were seen in eyes exposed to 460-nm or shorter wavelengths of light. The ONL thickness near the optic nerve head also tended to decrease with exposure to shorter wavelengths. The decreased ERG amplitudes and ONL thicknesses were most prominent in eyes exposed to 420-nm light at both radiant exposures. When the wavelengths were the same, the higher the amount of radiant exposure and the stronger the damage. Compared to the unexposed eyes, the a- and b-waves did not decrease significantly in eyes exposed to 500-nm or longer wavelength light. The results indicate that the retinal damage induced by visible light observed in albino rats depends on the wavelength and energy level of the exposed light.

Corneal damage-induced various wavelength UV (311, 254, 235, 222 and 207 nm) was evaluated in rats. For 207 and 222-UV-C, the threshold radiant exposure was between 10 000 and 15 000 mJ cm -2 at 207 nm and between 3500 and 5000 mJ cm -2 at 222 nm. Penetrate depth to the cornea indicated by cyclobutene pyrimidine dimer (CPD) localization immediately after irradiation was dependent on the wavelength. 311 and 254 nm UV penetrate to corneal endothelium, 235 nm UVC to the intermediate part of corneal stroma, 222 and 207 nm UVC only to the most outer layer of corneal epithelium. CPD observed in corneal epithelium irradiated by 222 nm UVC disappeared until 12 h after. The minimum dose to induce corneal damage of short-wavelength UV-C was considerably higher than the threshold limit value (TLV ® ) promulgated by American Conference of Governmental Industrial Hygienists (ACGIH). The property that explains why UV-C radiation at 207 and 222 nm is extremely less hazardous than longer UV wavelengths is the fact that this radiation only penetrates to the outermost layer of the corneal epithelium. These cells typically peel off within 24 h during the physiological turnover cycle. Hence, short-wavelength UV-C might be less hazardous to the cornea than previously considered until today., (© 2021 The Authors. Photochemistry and Photobiology published by Wiley Periodicals LLC on behalf of American Society for Photobiology.)

Introduction: Trabeculotomy (LOT) and related goniotomy surgeries are classified based on excision or incision of the trabecular meshwork (TM); however, histologic evidence of the incision/excision pattern is insufficient., Case Presentations: Two cases of glaucomatous eyes in which trabeculectomy specimens previously "incised" during LOT were assessed histologically. A 39-year-old man with juvenile open-angle glaucoma (case 1) and a 70-year-old man with exfoliation glaucoma (case 2) underwent trabeculectomy for insufficient intraocular pressure reduction or visual field progression after initial microhook ab interno trabeculotomy (μLOT). In case 1, Schlemm's canal (SC) opened into the anterior chamber due to extensive absence of the inner wall of SC and TM. In case 2, SC endothelium (SCE)-marker CD34 staining showed the slit-like entry site of a previous LOT, the SC lumen was sealed partially by scleral tissue, and CD34-positive and CD34-negative areas in the SC wall suggested SCE dropout and partial conversion of SC into ghost vessels. Active aqueous outflow-marker podoplanin (D2-40) staining showed intense immunolabeling in the sclera between the entry site and collector channels, indicating aqueous outflow., Discussion: The μLOT cleft can appear as both incisional and excisional patterns. In addition to incremental conventional outflow with reduced TM resistance, another unconventional outflow may be a mechanism of IOP reduction after LOT procedures., Competing Interests: Disclosure: The microhooks used were co-developed by M.T., and Inami & Co., Ltd, Tokyo, Japan, and provided by Inami & Co., Ltd. M.T. receives royalties from Inami & Co., Ltd. The remaining authors declare no conflict of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

We tested oral French maritime pine bark (40 mg)/bilberry fruit extract (90 mg) supplements for intraocular pressure-lowering effects in Japanese subjects with primary open-angle glaucoma. Eighteen subjects (29 eyes) were recruited with intraocular pressure of ≥15 mmHg who used one to three bottles of antiglaucoma medications. After a 2-week observation (period 1), subjects ingested a tablet/day of Sante ® Glagenox for 4 weeks (period 2). The mean intraocular pressure (17.2 ± 2.3 mmHg) decreased significantly to 15.7 ± 1.9 mmHg (8.7% reduction) at week 4 ( p  = 0.0046). The mean morning intraocular pressure (14.1 ± 3.1 mmHg) self-measured using the iCare HOME tonometer during period 1 decreased significantly to 13.3 ± 2.9 mmHg (5.7% reduction) during period 2 ( p  = 0.0291). Blood redox parameters, diacron reactive oxygen metabolites, biologic antioxidant potential, and sulfhydryl tests were unchanged after 4-week supplementation. Intra-subject comparisons, compared to period 1, showed pooled, self-measured, period-2 intraocular pressures was significantly lower in nine subjects (50%), unchanged in six subjects (33%), and elevated in three subjects (17%), suggesting some non-responders. Four-week supplementation with French maritime pine bark/bilberry fruit extracts can further reduce intraocular pressure even in Japanese patients with controlled primary open-angle glaucoma. Further study should confirm the intraocular pressure-lowering effects and mechanisms of this supplement in glaucoma management. The study was registered in UMIN (ID: UMIN000033200)., Competing Interests: MT received lecture fees, consultant fees, and research donations from Santen Pharmaceutical Co., Ltd. YT and EM are employees of Santen Pharmaceutical Co., Ltd., (Copyright © 2021 JCBN.)

The retinal vessel narrowing may be implicated in the pathogenesis of glaucoma; however, the association between systemic oxidative stress and retinal vessel diameter remains largely unknown. We examined the relationship between serum oxidative stress markers and retinal vessel diameters in eyes with primary open-angle glaucoma (POAG) and cataract, using central retinal artery equivalent (CRAE) and central retinal vein equivalent (CRVE). We included 66 eyes of 66 patients with POAG (37 men, 29 women; 65.4 ± 11.7 years) and 20 eyes of 20 patients with cataract (7 men, 13 women; 69.4 ± 9.0 years) as the controls. The CRAE ( p < 0.0001), CRVE ( p < 0.0001), and serum biological antioxidant potential (BAP) ( p = 0.0419) were significantly lower in the POAG group compared to the controls. The BAP showed significant correlation both with CRAE ( ρ = 0.2148, p = 0.0471) and systolic blood pressure ( ρ = -0.2431, p = 0.0241), while neither Diacron reactive oxygen metabolites nor sulfhydryl test correlated with them. The multivariate analyses indicated that age, best corrected visual acuity, and BAP were independent factors for CRAE or CRVE. The present study suggested that lower systemic antioxidant capacity was significantly associated with the intraocular pressure-independent vascular narrowing in POAG patients. This study provided a novel insight into the pathophysiology of glaucoma and highlighted the clinical impact on systemic antioxidant treatment for patients with glaucoma.

Oxidative stress is thought to play a significant role in the development of glaucoma. However, the association between systemic and local oxidative stresses in different types of glaucoma has not been assessed fully. The current study compared the redox status in the aqueous humor (AH) and blood samples among eyes with primary open-angle glaucoma (POAG), exfoliation glaucoma (EXG), and non-glaucomatous controls to evaluate the relationship among systemic redox status, intraocular oxidative stress, and clinical backgrounds. AH and blood samples were obtained from 45 eyes of 45 Japanese subjects (15 POAG, 15 EXG, and 15 control eyes). The serum levels of lipid peroxides, ferric-reducing activity, and thiol antioxidant activity were measured by diacron reactive oxygen metabolites (dROM), biologic antioxidant potential (BAP), and sulfhydryl (SH) tests, respectively, using a free radical analyzer. The activities of cytosolic and mitochondrial forms of the superoxide dismutase (SOD) isoforms, i.e., SOD1 and SOD2, respectively, in AH and serum were measured using a multiplex bead immunoassay. In AH, SOD1 in subjects with EXG and SOD2 in those with POAG and EXG were significantly higher than in control eyes. In serum, compared to control subjects, BAP in subjects with POAG and EXG was significantly lower; SOD1 in those with EXG and SOD2 in those with POAG and EXG were significantly higher. dROM and SH did not differ significantly among the groups. The BAP values were correlated negatively with the SOD1 concentrations in AH and serum, SOD2 in the AH, intraocular pressure, and number of antiglaucoma medications. In conclusion, lower systemic antioxidant capacity accompanies up-regulation of higher local antioxidant enzymes, suggesting increased oxidative stress in eyes with OAG, especially in EXG. Determination of the systemic BAP values may help predict the redox status in AH.

Intraocular stability during or after cataract and glaucoma filtration surgeries and vitreous surgery with a gas/silicone oil tamponade might differ among intraocular lenses (IOLs). We used six different one-piece IOL models and measured the force that displaced the IOLs from the vitreous cavity to anterior chamber as a measure of stability against the pressure gradient between the anterior and posterior IOL surfaces. We measured IOL hardness, haptics junction area, and posterior IOL bulge to identify what determines the IOL displacement force. The KOWA YP2.2 IOL (1.231 mN) required significantly greater force than the HOYA XY1 (0.416 mN, p = 0.0004), HOYA 255 (0.409 mN, p = 0.0003), Alcon SN60WF (0.507 mN, p = 0.0010), and Nidek NS60YG (0.778 mN, p = 0.0186) IOLs; J&J ZCB00V IOL (1.029 mN) required greater force than the HOYA XY1 ( p = 0.0032) and HOYA 255 ( p = 0.0029) IOLs; the Nidek NS60YG IOL required greater force than the HOYA 255 ( p = 0.0468) IOL. The haptics junction area was correlated positively with the IOL displacement force ( r = 0.8536, p = 0.0306); the correlations of the other parameters were non-significant. After adjusting for any confounding effects, the haptics junction area was correlated significantly with the IOL displacement force ( p = 0.0394); the IOL hardness ( p = 0.0573) and posterior IOL bulge ( p = 0.0938) were not. The forces that displace IOLs anteriorly differed among one-piece soft-acrylic IOLs, and the optics/haptics junction area was the major force determinant.

Germicidal lamps that emit primarily 254 nm ultraviolet radiation (UV) are routinely utilized for surface sterilization but cannot be used for human skin because they cause genotoxicity. As an alternative, 222-nm UVC has been reported to exert sterilizing ability comparable to that of 254-nm UVC without producing cyclobutane pyrimidine dimers (CPDs), the major DNA lesions caused by UV. However, there has been no clear evidence for safety in chronic exposure to skin, particularly with respect to carcinogenesis. We therefore investigated the long-term effects of 222-nm UVC on skin using a highly photocarcinogenic phenotype mice that lack xeroderma pigmentosum complementation group A (Xpa-) gene, which is involved in repairing of CPDs. CPDs formation was recognized only uppermost layer of epidermis even with high dose of 222-nm UVC exposure. No tumors were observed in Xpa-knockout mice and wild-type mice by repetitive irradiation with 222-nm UVC, using a protocol which had shown to produce tumor in Xpa-knockout mice irradiated with broad-band UVB. Furthermore, erythema and ear swelling were not observed in both genotype mice following 222-nm UVC exposure. Our data suggest that 222-nm UVC lamps can be safely used for sterilizing human skin as far as the perspective of skin cancer development., (© 2020 The Authors. Photochemistry and Photobiology published by Wiley Periodicals LLC on behalf of American Society for Photobiology.)

We reported previously that enzymatic and singlet oxygen-mediated fatty acid oxidation may be major oxidation pathways in subjects with primary open angle glaucoma, based on measurement of serum levels of hydroxylinoleate (HODE) and hydroxyarachidonate (HETE) isomers after reduction and saponification. In this study, we measured serum levels of HODE and HETE isomers to investigate the pathogenesis of exfoliation syndrome (EX). In total, 311 Japanese subjects comprising EX patients (n = 192) and non-glaucomatous control subjects (n = 119) were included in this study. Patients with EX (n = 192) were divided into EX with glaucoma (EXG) and EX without glaucoma (EXS) groups (n = 128 and n = 64, respectively) depending on the intraocular pressure. Total HODE (/linoleic acid) serum levels were significantly (p = 0.0426) higher in the EX group (202.7 ± 153.2 μmol/mol) than in the controls (167.1 ± 105.3 μmol/mol). Among the HODE isomers, the levels of 9-(E,E)-HODEs (p < 0.0001) and 13-(E,E)-HODEs (p < 0.0001), both free radical-mediated oxidation products, were higher in the EX and EXG groups than in the controls, whereas no significant difference was observed between EXS and controls. After adjusting for differences in demographic parameters, multivariate analyses confirmed the association between 9- and 13-(E,E)-HODEs and EX. This is the first report of a dramatic increase in free radical-mediated oxidation products related to the pathogenesis of EX, and our findings suggest that free radical-mediated oxidation can be one of the causes of deterioration in EX., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Two hundred twenty-two nanometres ultraviolet (UV) light produced by a krypton-chlorine excimer lamp is harmful to bacterial cells but not skin. However, the effects of 222-nm UV light exposure to the eye are not fully known. We evaluated acute corneal damage induced by 222- and 254-nm UV light in albino rats. Under deep anaesthesia, 6-week-old Sprague-Dawley albino rats were exposed to UV light. The exposure levels of corneal radiation were 30, 150, and 600 mJ/cm 2 . Epithelial defects were detected by staining with fluorescein. Superficial punctate keratitis developed in corneas exposed to more than 150 mJ/cm 2 of UV light, and erosion was observed in corneas exposed to 600 mJ/cm 2 of UV light. Haematoxylin and eosin staining also showed corneal epithelial defects in eyes exposed to 254-nm UV light. However, no damage developed in corneas exposed to 222-nm UV light. Cyclobutane pyrimidine dimer-positive cells were observed only in normal corneas and those exposed to 254-nm UV light. Although some epithelial cells were stained weakly in normal corneas, squamous epithelial cells were stained moderately, and the epithelial layer that was detached from the cornea exposed to 600 mJ/cm 2 of light was stained intensely in corneas exposed to 254-nm UV light. In the current study, no corneal damage was induced by 222-nm UV light, which suggested that 222-nm UV light may not harm rat eyes within the energy range and may be useful for sterilising or preventing infection in the future.

We examined the cytoprotective effect of quercetin via activator protein (AP-1) and the heat shock protein 70 (Hsp70) pathway against light-induced retinal degeneration in rats. Quercetin was administered intraperitoneally to Sprague-Dawley rats for seven days before light exposure to intense white fluorescent light (3000 lux) for 24 h. Light-induced retinal damage was determined by the number of rows of photoreceptor cell nuclei, the microstructures of the rod outer segments and retinal pigment epithelium, and terminal deoxynucleotidyl transferase (TdT)-mediated 2'-Deoxyuridine-5'-triphosphate (dUTP) nick end labeling. To elucidate the cytoprotective mechanism of quercetin, expression levels were measured in the rat retinas of 8-hydroxy-deoxyguanosine (8-OHdG), a marker of oxidative stress; Hsp70; and transcription factor AP-1 transcription activity. Pretreatment with quercetin inhibited light-induced photoreceptor cellular apoptosis and subsequent retinal degeneration in rats. 8-OHdG and Hsp70 protein expressions were up-regulated markedly by light exposure and suppressed by quercetin pretreatment. The results of an electrophoretic mobility shift assay showed that AP-1-binding activity was activated by light exposure, and binding of c-Fos and c-Jun, but not JunB, mediated the binding activity. Intraperitoneal administration of quercetin decreases photooxidative damage in the retina and mediates cytoprotection against light-induced photoreceptor cell degeneration in rats. Suppression of the heterodimeric combination of c-Jun and c-Fos proteins at the AP-1 binding site is highly involved in quercetin-mediated cytoprotection., Competing Interests: The authors declare no conflicts of interest.

We previously reported that lower systemic antioxidant capacity is involved in primary open-angle glaucoma (POAG) and exfoliation syndrome pathogeneses as measured by ferric-reducing activity. In the present study, we measured hydroxylinoleate (HODE) and hydroxyarachidonate (HETE) isomer serum levels after sample reduction and saponification to investigate POAG pathogenesis. POAG patients (n = 198) were recruited and divided into normal- and high-tension glaucoma groups (n = 84 and 114, respectively) depending on intraocular pressure. Total HODE (/linoleic acid) and HETE (/arachidonic acid) serum levels were significantly higher in the POAG group (211.9 ± 143.0 and 181.0 ± 164.1 µmol/mol, respectively) than in controls (167.1 ± 105.2 and 132.5 ± 139.7 µmol/mol, p = 0.0025 and 0.0101, respectively). The associations between HODEs/HETEs and glaucoma were further confirmed by multivariate analyses after adjusting for differences in demographic parameters. Among the HODE isomers, the levels of 9- and 13-(Z,E)-HODEs (p = 0.0014) and singlet oxygen-specific products (i.e., 10- and 12-(Z,E)-HODEs, p = 0.0345) were higher in the POAG group than in controls, while free radical-mediated oxidation-specific products (i.e., 9- and 13-(E,E)-HODEs, p = 0.0557) demonstrated a marginal difference. Enzymatic and singlet oxygen-mediated fatty acid oxidation may be major pathways of oxidation process in glaucoma subjects.

The purpose of this study was to determine whether carteolol eye drops, a β-adrenoceptor antagonist used as an intraocular hypotensive agent, has protective effects against the light-induced oxidative stress in retina. Dark-adapted pigmented rats were pre-treated with topical carteolol ophthalmic solution or saline and then exposed to visible light. The effects on electroretinogram (ERG), morphology, oxidative stress, and expression of mRNAs in the retinas were determined. The l-buthionine-(S,R)-sulfoximine (BSO)/glutamate-induced oxidative stress in 661 W cells, a murine photoreceptor cell line, was evaluated by cell death assays, production of reactive oxygen species (ROS), and activation of caspase. In vivo studies showed that exposure to light caused a decrease in the amplitudes of ERGs and the outer nuclear layer (ONL) thickness and an increase of the 8-hydroxy-2'-deoxyguanosine (8-OHdG)-positive cells in the ONL. These changes were significantly reduced by pre-treatment with carteolol. Carteolol also significantly up-regulated the mRNA levels of thioredoxin 1 and glutathione peroxidase 1 compared to saline-treated group. Moreover, carteolol and timolol, another β-adrenoceptor antagonist, significantly inhibited BSO/glutamate-induced cell death and reduced caspase-3/7 activity and ROS production in vitro. Therefore, carteolol could protect retina from light-induced damage with multiple effects such as enhancing the antioxidative potential and decreasing the intracellular ROS production., (Copyright © 2018 The Authors. Production and hosting by Elsevier B.V. All rights reserved.)

Retinal tissue is exposed to oxidative stress caused by visible light. Light-damaged rat used in age-related macular degeneration (AMD) studies clarified that antioxidants decrease retinal light damage. Albino rats were exposed to 5000 Lux light for 12 h with oral administration of the polyphenolic compounds fraction (PF) from the seed shells of Japanese horse chestnut (30 mg/kg, 100 mg/kg, and 300 mg/kg body weight: BW). To evaluate the protective effects against light damage, electroretinograms (ERGs), the outer nuclear layer (ONL) thickness, the antioxidant activity of plasma, oxidized retinal lipids, and the detection of apoptosis were examined. To reveal their active compounds, PF were separated into an A-type proanthocyanidin (PAF) and a flavonol O -glycosides fraction. The protective effects of these fractions against light damage were compared by measuring the thickness of the ERGs and ONL. Compared with the negative control, the PF group (100 mg/kg and 300 mg/kg BW) significantly suppressed the decrease of the ERG amplitudes and ONL thickness. PF (300 mg/kg BW) induced the elevation of in vivo antioxidant activity, and the suppression of retinal lipid oxidation. PF administration also suppressed apoptotic cell death. The protective effects against light damage were attributable to the antioxidant activity of PAF. The light-induced damage of retinas was protected by oral administration of PF and PAF. Taken together, these compounds are potentially useful for the prevention of the disease caused by light exposure., Highlights: The protective effects of retinal damage by light exposure were evaluated using polyphenolic compounds from the seed shells of Japanese horse chestnut ( Aesculus turbinata BLUME) as an antioxidant. Decreases in the electroretinographic amplitude and outer nuclear layer thickness were suppressed by the polyphenolic compounds of the seed shells. Polyphenolic compounds from the seed shells of Japanese horse chestnut inhibited the oxidation of retinal lipids. Highly polymeric A-type proanthocyanidin from the seed shells protected the rat retina from light exposure damage by inhibiting oxidative stress and apoptotic mechanisms.

Age-related macular degeneration (AMD) is the leading cause of blindness worldwide. Although the cause of AMD remains unknown, lipid peroxidation (LPO) end-products are critical molecules for its development. Herein, we report the imaging of lipid radicals, which are key factors in the LPO reaction, and therapeutic information using animal models.

Interleukin (IL)-1β, a proinflammatory cytokine, is a key mediator in several acute and chronic neurological diseases. Thioredoxin-1 (TRX1) acts as an antioxidant and plays a protective role in certain neurons. We examined whether exogenous TRX1 exerts axonal protection and affects IL-1β levels in tumor necrosis factor (TNF)-induced optic nerve degeneration in rats. Immunoblot analysis showed that IL-1β was upregulated in the optic nerve after intravitreal injection of TNF. Treatment with recombinant human (rh) TRX1 exerted substantial protective effects against TNF-induced axonal loss. The increase in the IL-1β level in the optic nerve was abolished by rhTRX1. Treatment with rhTRX1 also significantly inhibited increased glial fibrillary acidic protein (GFAP) levels induced by TNF. Immunohistochemical analysis showed substantial colocalization of IL-1β and GFAP in the optic nerve after TNF injection. These results suggest that IL-1β is upregulated in astrocytes in the optic nerve after TNF injection and that exogenous rhTRX1 exerts axonal protection with an inhibitory effect on IL-1β., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Purpose: To compare changes in macular pigment optical density (MPOD) and serum lutein concentration between free lutein and lutein esters supplements in healthy Japanese individuals., Methods: Twenty healthy subjects (age range, 22-47 years) were recruited into this prospective, randomized, doubled-blind comparative study. Individuals were evenly divided into two groups: free lutein group, supplementation with 10 mg of free lutein; or lutein esters group, supplementation with 20 mg of lutein esters equivalent to 10 mg of free lutein. Each participant took either type of oral lutein daily for 3 months. The serum lutein concentrations and MPOD levels were measured at baseline and 3 and 6 months after the start of supplementation., Results: There were no significant differences in the serum lutein concentrations and MPOD levels at baseline between the groups. The increased serum lutein concentration and MPOD levels at 3 months were respectively, 89% and 38% in the free lutein group and 97% and 17% in the lutein esters group. The serum lutein concentrations in both groups and MPOD levels in the free lutein group increased significantly (p < 0.05) from baseline. No significant differences in serum lutein concentrations and MPOD levels were seen between the groups. Three months after supplementation ended, the serum lutein concentration decreased; the MPOD remained elevated in both groups., Conclusions: The serum lutein concentrations and MPOD levels increased significantly with either free lutein or lutein esters, and no significant differences were found between the two. Both were considered useful as lutein supplements., (© 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Local and systemic oxidative stress in intraocular pressure (IOP) elevation and optic nerve damage may be involved in the pathogenesis of glaucoma. We reported previously that a lower level of systemic antioxidative capacity is associated with IOP elevation in open-angle glaucoma (OAG). We assessed the correlation between the visual field sensitivity value, i.e., mean deviation (MD), and systemic levels of prooxidants and antioxidants by analyzing the blood biochemistry in 202 patients with glaucoma. Serum levels of lipid peroxides, ferric-reducing activity, and thiol antioxidant activity were measured using the diacron reactive oxygen metabolite (dROM), biological antioxidant potential (BAP), and sulfhydryl (SH) tests, respectively, using a free-radical analyzer. Univariate and multivariate analyses suggested a positive correlation between MD and BAP (R = 0.005 and P = 0.0442 by a multiple regression model adjusted for seven demographic parameters), but no significant associations between the MD and the dROM (R = 0.002 and P = 0.8556) and SH tests (R = -0.001 and P = 0.8280). Use of more antiglaucoma medication and primary OAG rather than normal tension glaucoma also were associated significantly with worse visual field damage. This large and comprehensive assessment of the association between systemic redox status and visual field damage in OAG suggests that lower systemic antioxidant capacity measured by ferric-reducing activity is associated with more severe visual field damage in OAG that partly explained its roles in IOP elevation.

Background: The involvement of local and systemic oxidative stress in intraocular pressure (IOP) elevation and optic nerve damage has been hypothesized in the pathogenesis of glaucoma. We reported previously that the level of systemic antioxidative capacity is lower in patients with open-angle glaucoma than controls without glaucoma. Here, we assessed the correlation between IOP and systemic levels of prooxidants and antioxidants by analyzing the blood biochemistry in patients with glaucoma., Methods: Peripheral blood samples were collected from Japanese patients with primary open-angle glaucoma (n = 206), exfoliation syndrome (n = 199), and controls (n = 126). Serum levels of lipid peroxides, ferric-reducing activity, and thiol antioxidant activity were measured by diacron reactive oxygen metabolite (dROM), biological antioxidant potential (BAP), and sulfhydryl (SH) tests, respectively, using a free radical analyzer. To test the possible effect of oxidative stress on IOP levels, the patients were classified into one of four groups (Q1, Q2, Q3, and Q4, with Q1 having the lowest IOP) based on the quartile value of IOP. For this classification, the known highest IOP value in both the right and left eyes was regarded as each subject's IOP. For comparisons among the IOP groups, the differences were calculated using one-way analysis of variance followed by post-hoc unpaired t-tests. To adjust for differences in demographic characteristic distributions, the dROM, BAP, and SH test values were compared among the IOP groups using multiple logistic regression analysis; the odds ratio (OR) of each variable was calculated with the Q1 group as the reference., Results: The dROM and the SH levels did not differ significantly (p = 0.6704 and p = 0.6376, respectively) among the four IOP groups. The BAP levels differed significantly (p = 0.0115) among the four IOP groups; the value was significantly lower in the Q4 group (1,932 μmol/L) compared with the Q1 (2,023 μmol/L, p = 0.0042) and Q2 (2,003 μmol/L, p = 0.0302) groups and significantly lower in the Q3 group (1,948 μmol/L) than the Q1 (p = 0.0174) group. After adjustment for differences in various demographic characteristics, lower BAP values were significantly associated with the classification into higher IOP groups (Q3 group, p = 0.0261 and OR = 0.06/range; Q4 group, p = 0.0018 and OR = 0.04/range). The dROM and SH values did not reach significance in any comparisons., Conclusions: Lower systemic antioxidant capacity measured by ferric-reducing activity is involved in the pathogenesis of open-angle glaucoma via its roles in IOP elevation.

Purpose: A possible association has been reported between exfoliation syndrome (EX) and various ocular and systemic vascular disorders; however, it is unclear if there is an association between EX and central retinal vein occlusion (CRVO). Because latent deposits of exfoliation materials might not be recognized during slit-lamp examination, an ocular biopsy is required to establish a precise diagnosis. We evaluated a possible association between EX and CRVO using lysyl oxidase-like 1 (LOXL1) gene variants as alternative markers for EX., Methods: The allelic and genotypic frequencies of three LOXL1 variants (rs1048661, rs3825942, and rs2165241) were determined in 68 consecutive Japanese patients with CRVO [15 with exfoliation syndrome (EX+) and 53 without exfoliation syndrome (EX-)] and 90 control patients with cataract without EX (CT)., Results: The frequencies of the rs1048661 and rs3825942 variants showed borderline difference between the CRVO and CT groups (p = 0.04085 and p = 0.06088, respectively, for allelic frequencies, and p = 0.06838 and p = 0.03482, respectively, for genotypic frequencies). Compared with the CT group, subgroup analysis showed that the CRVO EX+ group had significant differences in the allelic and genotypic frequencies of rs1048661 (p = 0.0006447 and p = 0.0001392, respectively) and had borderline differences in the allelic and genotypic frequencies of rs3825942 (p = 0.03403 and p = 0.07341, respectively), while the CRVO EX- group did not (p = 0.1324-0.6306). Subgroup analysis showed that the frequencies of rs2165241 did not differ between the CRVO and CT groups., Conclusions: When the LOXL1 variants were used as disease markers for clinically undetectable EX, there was no association between CRVO and EX. The results suggested that the LOXL1 variants, which are well-established markers for EX, are not likely genetic markers for CRVO in Japanese subjects., (© 2014 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Oxidative stress has been suspected of contributing to the pathogenesis of pterygia. We evaluated the immunohistochemical localization of the markers of oxidative stress, that is, the proteins modified by 4-hydroxyhexenal (4-HHE) and 4-hydroxynonenal (4-HNE), which are reactive aldehydes derived from nonenzymatic oxidation of n-3 and n-6 polyunsaturated fatty acids, respectively. In the pterygial head, labeling of 4-HHE- and 4-HNE-modified proteins was prominent in the nuclei and cytosol of the epithelium. In the pterygial body, strong labeling was observed in the nuclei and cytosol of the epithelium and proliferating subepithelial connective tissue. In normal conjunctival specimens, only trace immunoreactivity of both proteins was observed in the epithelial and stromal layers. Exposures of ultraviolet (330 nm, 48.32 ± 0.55 J/cm(2)) or blue light (400 nm, 293.0 ± 2.0 J/cm(2)) to rat eyes enhanced labeling of 4-HHE- and 4-HNE-modified proteins in the nuclei of conjunctival epithelium. Protein modifications by biologically active aldehydes are a molecular event involved in the development of pterygia.

Background: The involvement of local and systemic oxidative stress in intraocular pressure (IOP) elevation and optic nerve damage has been hypothesized in the pathogenesis of glaucoma. To test this, we measured the systemic levels of prooxidants and antioxidants by analyzing the blood biochemistry in patients with glaucoma., Methods: Peripheral blood samples were collected from Japanese patients with primary open-angle glaucoma (PG) (n = 206), exfoliation syndrome (EX) (n = 199), and controls (n = 126). Plasma levels of lipid peroxides, ferric-reducing activity, and thiol antioxidant activity were measured by diacron reactive oxygen metabolites (dROM), biological antioxidant potential (BAP), and sulfhydryl (SH) tests, respectively, using a free radical analyzer., Results: In the PG, EX, and control groups, the mean ± standard deviation values were 355±63, 357±69, and 348±56 (U. Carr), respectively, for dROM; 1,951±282, 1,969±252, and 2,033±252 (µmol/L), respectively, for BAP (µmol/L); and 614±98, 584±91, and 617±99 (µmol/L), respectively, for SH. The differences in the BAP values were significant between the PG and control groups (p = 0.0062), for SH between the EX and control groups (p = 0.0017), and for SH between the PG and EX groups (p = 0.0026). After adjustment for differences in age and sex among groups using multiple regression analysis, lower BAP values were correlated significantly with PG (p = 0.0155) and EX (p = 0.0049). Higher dROM values with and without glaucoma were correlated with female gender, and lower SH values with older age. There were no significant differences between the higher (≥21 mmHg) and lower (<21 mmHg) baseline IOPs in the PG group or between the presence or absence of glaucoma in the EX group., Conclusions: Lower systemic antioxidant capacity that measured by ferric-reducing activity is involved in the pathogenesis of PG and EX.

Purpose: Previous studies have described a possible association between exfoliation syndrome (EX) and various ocular and systemic vascular disorders; however, the association between EX and branch retinal vein occlusion (BRVO) remains unclear. Because slit-lamp examination may overlook latent deposits of exfoliation materials, an ocular biopsy is usually needed for a precise diagnosis. We evaluated a possible association between EX and BRVO using lysyl oxidase-like 1 (LOXL1) gene variants as alternative markers for EX., Methods: Allelic and genotypic frequencies of three LOXL1 variants (rs1048661, rs3825942, and rs2165241) were determined for 78 consecutive Japanese patients with BRVO (11 patients with exfoliation syndrome [EX+], 67 patients without exfoliation syndrome [EX-]), and 158 patients with cataract without EX (CT) as controls., Results: The rs1048661 variant differed between the BRVO and CT groups in allelic and genotypic frequencies (p=0.0137 and p=0.0203, respectively). Subgroup analysis, compared to the CT group, showed that BRVO EX+ had significantly different allelic and genotypic frequencies of rs1048661 (p=0.00011 and p=0.000189, respectively), while BRVO EX- did not (p=0.175 and p=0.288, respectively). The frequencies of rs3825942 and rs2165241 did not differ between the BRVO and CT groups., Conclusions: No association was found between BRVO and EX if LOXL1 variants were used as disease markers for clinically undetectable EX. The results suggested that LOXL1 variants, well established markers for EX, are not likely genetic markers for BRVO in Japanese subjects.

Previous studies have shown that retinal damage induced by damaging light exposure is more severe in superior retina than inferior retina when measured along the vertical meridian of eyes. However, the extent of retinal damage over all retinal regions is not clear. Albino rats were exposed to bright light (5000 lux for 6h) and eyes removed 7 days later. Outer nuclear layer (ONL) thickness was measured along four different meridians; temporal-to-nasal (T-N), superior-to-inferior (S-I), superiotemporal-to-inferionasal (ST-IN), and superionasal-to-inferiotemporal (SN-IT). As reported previously, superior retina is more severely damaged than inferior retina along the S-I meridian. In addition, we found that the temporal retina is more severely damaged than nasal retina on the T-N meridian. Color-coded topographic maps clearly revealed that thinning of ONL was greatest at 1-1.5mm superior and superiotemporal to the optic nerve head and that most damage was in the superiotemporal region of the fundus. For consistency in quantification of ONL thickness, using retinal sections cut along the S-I meridian is preferable to using those along the T-N meridian, since minor orientations to superior or inferior directions along the T-N meridian may cause greater variations in measured ONL thickness values in this experimental model.

Protein modifications resulting from reactive aldehydes are thought to be involved in the pathogenesis of various degenerative diseases. Aged cynomolgus monkey (Macaca fascicularis) spontaneously develop drusen in the macula, consistent with the phenotype observed in early-stage age-related macular degeneration (AMD), indicating that this animal is an optimum model for AMD. In retinal sections from three monkeys with macular degeneration, regardless of their size, drusen were consistently positive with immunohistochemical labeling against protein modifications by 4-hydroxynonenal and 4-hydroxyhexenal, end products of non-enzymatic oxidation of n-6 and n-3 polyunsaturated fatty acids, respectively. Positive labeling for both modifications was observed in the ganglion cell layer, the inner nuclear layer, the outer nuclear layer, and the retinal pigment epithelium. However, no consistent differences in location or intensity of the labeling were observed between monkeys with normal macula and macular degeneration. The results suggest a possible association between drusen formation and protein modifications by aldehydes in the pathogenesis of AMD.

Purpose: To evaluate the association of lysyl oxidase like 1 (LOXL1) gene variants in Japanese patients with open-angle glaucoma., Methods: We evaluated the association of three LOXL1 variants (rs1048661, rs3825942, and rs2165241) in 142 Japanese patients with exfoliation syndrome (EX; n=59) and exfoliation glaucoma (EG; n=83) as well as in 251 control patients aged 70 years or older with primary open-angle glaucoma (PG; n=40), normal tension glaucoma (NG; n=54), and cataract (CT; n=157)., Results: In comparison with the CT group, the single nucleotide polymorphisms (SNPs) showed significant association with EX, EG, and EX+EG. The odds ratio (OR)=19.71-28.23 and p=1.69 x 10(-23) - 3.00 x 10(-45) for allele T of rs1048661; OR=28.21-39.78 and p=1.77 x 10(-8) - 2.42 x 10(-22) for allele G of rs3825942; and OR=16.59-23.40 and p=4.79 x 10(-5) - 1.08 x 10(-9) for allele C of rs2165241. In comparison with the controls (CT+PG+NG), the haplotype rs1048661/rs3825942 (T/G) was significantly associated with EX+EG (p=8.27 x 10(-44)), and haplotype G/A had a significant protective effect (p=2.25 x 10(-14)). None of the three SNPs showed significant differences between the EX and EG groups or between the PG and NG groups., Conclusions: These SNPs are associated with exfoliation syndrome/glaucoma in the Japanese population. The risk alleles in rs1048661 and rs2165241 are different from other populations. Additional genetic or environmental risk factors other than these LOXL1 SNPs could be associated with the development of exfoliation syndrome as well as exfoliation glaucoma among exfoliation syndrome patients.

Purpose: To examine the long-term effects of acute photooxidative stress in the retina, retinal pigment epithelium (RPE), and choroid., Methods: Albino rats injected with either the protective antioxidant phenyl-N-tert-butylnitrone (PBN) or saline 30 minutes before exposure to 5 klx white fluorescent light for 6 hours were kept for up to 3 months in 5 lux cyclic light. Electroretinograms were recorded, and the outer nuclear layer (ONL) and the choroidal thickness and area were measured after hematoxylin-eosin (H&E) staining. The expression of rod, cone, and RPE cell markers was detected by Western blotting, and apoptosis was analyzed by TUNEL staining. Oxidative stress was analyzed by immunohistochemistry against 4-hydroxynonenal (4-HNE)-modified proteins. Retinal and choroidal ultrastructures were observed by transmission electron microscopy (TEM). Choroidal circulation was analyzed by in vivo staining of the choroidal layer by trypan blue., Results: In the saline-injected animals, TUNEL- and 4-HNE-labeling in the ONL, RPE, and choroid were higher 24 hours and 7 days after light exposure, and ERG amplitude, ONL and choroidal thickness and area, and rhodopsin and RPE65 expression were lower 7 or more days after light exposure than in phenyl-N-tert-butylnitrone (PBN)-injected animals. In the saline-injected animals, the expression of mid-wavelength opsin and the presence of cone cells in the ONL and the choroidal circulation were preserved for 7 days after light exposure but started to decrease by 1 month and continued to decrease for 3 months after light exposure. An increase in TUNEL-positive cells was observed in the ONL at the inferior peripheral retina, just behind the iris, by 3 months after light exposure. Delayed loss of cone cells, remaining rod cells, and choroidal circulation were counteracted by PBN treatment., Conclusions: Although cone cells are resistant to cell damage induced by acute photooxidative stress, progressive loss of cone cells continued for up to 3 months after light exposure. Impaired choroidal circulation is likely to be involved in the mechanism of delayed photoreceptor cell death after light exposure. Preserving choroidal circulation may provide a novel target for preserving the cone and the remaining rod cells in patients with retinal degeneration such as retinitis pigmentosa.

Purpose: To assess the role of vitamin E (VE) in age-related changes in the retinal tissues by using a mouse model of severe VE deficiency., Methods: Pups of alpha-tocopherol transfer protein null (a-TTP(-)(/)(-)) mice were fed a VE-deficient diet for 4 or 18 months (VE (-) group). Wild-type C57BL/6 mice were fed a 0.002% alpha-tocopherol-supplemented diet (VE (+) group). In various ocular tissues, the VE levels were measured by high-performance liquid chromatography; the fatty acid composition by gas chromatography (GC); and the hydroxyoctadecadienoic acid and 8-iso-prostaglandin F(2)(alpha) levels, which are biomarkers for lipid peroxidation, by GC-mass spectrometry. The retinal structure was assessed by light, electron, and fluorescence microscopy., Results: The alpha-tocopherol level in the retinas obtained from 4-month-old VE (-) animals was 71-fold lower than that in the retinas obtained from the VE (+) group. In addition, gamma-tocopherol was not detected; thus, the VE (-) group demonstrated a more severe VE deficiency than ever reported. In this group, the concentration of n-3 polyunsaturated fatty acids decreased (0.3- to 0.9-fold), whereas that of other classes of fatty acids was unchanged or increased. At 18 months of age, the number of the outer nuclear layer (ONL) nuclei was observed to be 17% lower in the VE (-) than in the VE (+) group (P < 0.05). Electron microscopy revealed larger amounts of matrix between the ONL nuclei indicating the Müller cell hypertrophy, greatly expanded rod outer segment discs, and a larger number of inclusion bodies in the retinal pigment epithelium (RPE; P < 0.05) in the VE (-) group. Fluorescence microscopy revealed that the autofluorescence signal was increased in the RPE layer in this group. When the observations of the 18-month-old animals were compared to those of the 4-month-old animals, the hydroxyoctadecadienoic acid and 8-iso-prostaglandin F(2)(alpha) levels were found to be increased in the retina and RPE obtained from both the VE (-) and VE (+) groups; however, the age-related increases were more remarkable in the VE (-) group (2.6- to 43.5-fold) than in the VE (+) group (0.8- to 8.7-fold)., Conclusions: The combined use of a-TTP(-)(/)(-) mice and a VE-deficient diet leads to a severe deficiency of VE, enhances lipid peroxidation in the retina, and accelerates degenerative damage of the retina with age.

Recently, a yellow intraocular lens (IOL) was developed for the purpose of reducing potential blue light-induced retinal damage after cataract surgery. However, the effect of yellow filters on retinal protection remains to be clarified. To test the protective effects of yellow filters on blue light-induced retinal damage, a yellow and a clear soft acrylic filter were attached to the right and left eyes, respectively, of albino rats and exposed to 4.5 k lux blue fluorescent lights with peak wavelength at 420 nm (ranging 380-500 nm; short blue) or 446 nm (ranging 400-540 nm; long blue) for 6h. To assess retinal damage, the electroretinogram (ERG) was recorded at 7 days, outer nuclear layer (ONL) thickness and area were measured at 7 days, apoptosis was analyzed by TUNEL staining at 24 h, and the level of lipid peroxidation in retinas was assessed by Western dot blots using specific antibodies against 4-hydroxynonenal (4-HNE)- and carboxyethylpyrrole (CEP)-modified proteins immediately after light exposure. After short blue light exposure, a- and b-wave ERG amplitudes and the ONL thickness at 1-2.5 mm inferior and 0.5-2.5 mm superior to optic nerve head (ONH) were significantly reduced. TUNEL staining in the ONL at 0-2 mm inferior and 1-2 mm superior to the ONH, and retinal levels of 4-HNE- and CEP-modified proteins were significantly increased in the clear filter-covered eyes compared to yellow filter-covered eyes. After long blue light exposure, the only difference seen was a greater ONL thickness at 1.5 mm superior to the ONH in yellow filter-covered eye. Transmission of light through the yellow filter was 58% for short blue and 89% for long blue compared to the clear filter. The ONL area was not different between clear filter-covered and -uncovered eyes after exposure to short or long blue light. Given the results, yellow IOL material protects the retina against acute shorter wavelength blue light exposure more effectively than the clear IOL material.

Exposure to excessive light induces retinal photoreceptor cell damage, which may involve lipid peroxidation. Morphological changes and the detection of internucleosomal DNA fragmentation confirmed the retinal damage caused by exposure of the retina of Balb/c mice to white fluorescent light (5000 lux, 2 h). The total amounts of hydroxyoctadecadienoic acid (tHODE) and 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha) in the retinas obtained from light-exposed mice were assessed after reduction and saponification. In this method, both the free and ester forms of hydroperoxides, hydroxides, and ketones of linoleic acid are measured as tHODE by gas chromatography-mass spectrometry (GC-MS) analysis. When compared with controls, a significant increase in the concentrations of tHODE and 8-iso-PGF2alpha was observed 24 h after light exposure. Furthermore, the stereoisomeric ratio (Z,E)-HODE/(E,E)-HODE decreased after light exposure, suggesting the involvement of free-radical-mediated peroxidation. By the immunohistochemical technique, it was confirmed that 8-iso-PGF2alpha increased in the inner plexiform layer (IPL), outer plexiform layer (OPL), rod outer segment, and choroidal layer, while 13-HODE increased in the OPL and rod inner segment after light exposure. These results demonstrate that tHODE and 8-iso-PGF2alpha assessed by the present method are appropriate biomarkers responding to retinal photooxidative stress in vivo.

A rat strain with congenital nuclear cataracts has been established. Segregation analyses indicated that this phenotype had an autosomal recessive mode of inheritance, implying that a loss of function mutation of a single autosomal gene was responsible. The gene was mapped to the D15Rat6 locus on chromosome 15 through a linkage analysis using 93 backcrossed rats. The connexin 46 gene (Gja3) was found to be located close to the locus, and was regarded as a strong candidate because of its pivotal role in the lens fiber cells. Expression of the gene in the lens was comparable between the cataract and control rats when evaluated with immunohistochemistry and reverse transcription-polymerase chain reaction. However, a non-conservative missense mutation, Glu42Lys, was found in the gene of the cataract rats, which was likely to be responsible for the pathogenesis. This strain will be useful in pathophysiological studies on nuclear cataracts.

Purpose: To analyze whether rebamipide (REB) and carteolol hydrochloride (CH) protect against UVB-induced corneal damage in mice., Methods: BALB/c mice topically pretreated with REB (1 and 10 mM) or CH (1, 10, and 100 mM) were exposed to ultraviolet (UV) B light at 416 micro W/cm(2). To evaluate corneal damage, mire irregularity was graded, and the haze index was estimated by using digitized corneal images. The formation of oxidized DNA in the corneal epithelium resulting from UVB exposure was estimated by using quantitative immunohistochemistry for 8-hydroxy-2-deoxyguanosine (8OHdG index). To analyze the mechanism of cytoprotection by REB and CH against UVB-induced cell damage, the UV absorption spectrum in these agents was evaluated by spectrophotometry, and their hydroxyl radical scavenging effect was evaluated by the electron spin resonance (ESR) spin trapping technique with Fenton system hydroxy radical generation., Results: Seventy-two hours after UVB exposure, the severity of mire irregularity, haze index, and 8OHdG index were significantly lower in mice pretreated with 10 mM (P < 0.05, P < 0.05, and P < 0.01, respectively) of REB and in mice pretreated with 10 mM (P < 0.05, P < 0.01, and P < 0.01, respectively) and 100 mM (P < 0.01, P < 0.01, and P < 0.01, respectively) of CH compared with mice treated with vehicle. The absorption spectrum of REB overlapped with the UVB wavelength, and that of CH overlapped partially. The ESR spin signal corresponding to the hydroxyl radical was reduced by the addition of REB or CH., Conclusions: REB and CH attenuate UVB-induced corneal damage, which may be partly responsible for their sunscreening and hydroxyl radical scavenging effects.

Hormone-producing cells in the rat anterior pituitary gland are not randomly distributed; rather, there are specific topographic affinities among five cell types (Noda et al., Acta Histochem. Cytochem. 2001;34:313-319). In this study we reconstructed these affinities, at least partially, in primary monolayer culture. Pituitary cells collected from adult male rats were enzymatically dispersed and cultured for 72 hr at a density of 1 x 10(5) cells/cm(2). We double-immunostained cells using antibodies against hormones, and then used confocal laser microscopy to examine the ability of the cells to attach to each other. We also statistically analyzed the affinity of all combinations of the five types of hormone-producing cells. We observed clusters by electron microscopy to identify junctional complexes between the cells. Confocal laser microscopy indicated that the features and attachment patterns of hormone-producing cells in vivo were similar to those in vitro. Statistical analyses revealed that the rates at which the five types of hormone-producing cells attached to growth hormone (GH)-, prolactin (PRL), and luteinizing hormone (LH)-producing cells were unequal, which suggests there are specific topographic affinities. The specific rates of adrenocorticotropic hormone (ACTH)-producing cell attachment to GH cells, LH to PRL cells, and PRL to LH cells were high, whereas that of PRL attachment to PRL cells was low. In addition, the rates correlated with the data from our previous in vivo study. Ultrastructural observations revealed few junctional complexes between hormone-producing cells. These results indicate that anterior pituitary hormone-producing cells can attach to specific types of cells by means of specific and/or nonspecific adhesion factors, and can reconstruct the topographic nature of the pituitary gland., (Copyright 2003 Wiley-Liss, Inc.)

Purpose: To examine the hypothesis that glutathione peroxidase (GPX) is induced at different time points after retinal exposure to light and localizes in different retinal cells., Methods: The rats were kept in cyclic light for 2 weeks before the experiments. The animals were maintained in 12-hour light-dark cycles, before and after exposure to intense white fluorescent light, for as long as 24 hours and then returned to cyclic light. Expression of GPX was measured by immunohistocytochemistry and Western and Northern blot analyses. Light-induced retinal damage was determined by the thickness of the outer nuclear layer (ONL) thickness in relation to total retinal thickness., Results: GPX labeling did not appear in the photoreceptor inner segments, and slight labeling was observed in the photoreceptor outer segments or the retinal pigment epithelial (RPE) cells in the normal retina kept in cyclic light. In retinal specimens maintained in light for 12 and 24 hours, GPX labeling was induced in the photoreceptor outer segments and RPE cells. High expression of GPX in the RPE was sustained until day 7 after challenge. In contrast, GPX expression in the photoreceptor outer segments decreased on day 1 and disappeared on days 3 and 7 after exposure. Intense GPX labeling was seen from the internal limiting membrane to the ganglion cell layer. GPX labeling was constantly localized in both high-intensity white light and cyclic conditions, suggesting no induction of GPX in those areas. In addition, GPX labeling was apparent at the posterior retinal pole but not at the peripheral retina. We observed marked upregulation of GPX mRNA in rats kept in high-intensity white light. One, 3, and 7 days after exposure to high-intensity white light, there was a significant difference (P < 0.0001) between the control and experimental groups in the ratio of the outer nuclear layer thickness to the entire retina., Conclusions: GPX was induced at different time points after exposure to high-intensity white light and localized in different retinal cells. Changes in expression of GPX after exposure to light may be related to the difference in susceptibility of the retina to damage by light.

Scanning electron microscopy (SEM) observation showed that fully differentiated spherical adipocytes were embraced by a network of collagens and fibroblastic preadipocytes. The properties of both the collagen networks and the preadipocytes allow the adipocytes to be interconnected, forming a fat-cell cluster, which can anchor to the bottom of a culture dish. In this network structure, collagen fibrils and fibrillar bundles were closely arranged and stratified. We found that immunostained collagens appeared to form extracellular network structures, which can be observed by SEM. The extracellular network of fibronectin was the first to develop among the extracellular matrix (ECM) components, though it became degraded with the progress of adipocyte differentiation. The type I collagen network was the last to develop and remained well organized through the late stage of adipocyte differentiation. The extracellular networks of type III, V, and VI collagen developed by the mid-stage and remained in the late stage of adipocyte differentiation. The network structures of type IV collagen and laminin became degraded during the differentiation process and localized at the surface of spherical cells. In addition to these basement membrane components, types III, V, and VI collagens also showed pericellular spherical staining patterns. These results demonstrated that the constitution and distribution of the ECM are altered during adipocyte differentiation, suggesting that the organization of each ECM component into a suitable structure is a requirement for the differentiation and maintenance of unilocular adipocytes.