Visual Function and Visual Perception among Senior Citizens with Mild Cognitive Impairment in Taiwan.

Purpose: With the benefits of advanced medical technology, Taiwan has gradually changed from an aged society to a super-aged society. According to previous studies, the prevalence rate of mild cognitive impairment (MCI) over the age of 60 is 15% to 20%. Therefore, the main purpose of our study was to analyze the correlation of cognitive function with visual function (specifically, binocular vision and visual perception) in Taiwanese volunteers aged 60 years or older. Methods: Thirty-six healthy participants who were not taking psychiatric medications and who had not been diagnosed with any retinal or optic nerve diseases were enrolled. Addenbrooke's cognitive examination III (ACE-III), binocular visual function, and visual perception evaluation were performed, and the data analyzed statistically by t-test, χ2, linear regression, and MANOVA. Results: Cognitive function was closely correlated with visual function and visual perception; the horizontal adjustment time of binocular eye movement, stereopsis, the motor-free visual perception test-4 (MVPT-4), and peripheral awareness actually displayed higher explanatory power in predicting cognitive function. In addition, various interactive parameters between visual function and visual perception were found to affect specific aspects of ACE-III. Discussion: Our study revealed that there was a close correlation of cognitive function with visual function; as such, it may be possible to predict visual function deficits in patients with mild cognitive impairment.

All-optically controllable nanoparticle random laser in a well-aligned laser-dye-doped liquid crystal.

This study reports for the first time an all-optically controllable nanoparticle random laser (NPRL) in a well-aligned laser-dye-doped liquid crystal (LDDLC) cell added with NPs and azo-dyes. Experimental results display that the NPRL can be obtained when the pumped energy exceeds the energy threshold (~3.5 µJ/pulse). The occurrence of the NPRL is attributable to the enhancement of the fluorescence by the multi-scattering events of the fluorescence photons from the randomly distributed NPs in the diffusion rout of the well-aligned LDDLC cell. In addition, the lasing intensity of the NPRL can decrease with increasing irradiation time of one UV beam. Continuing irradiation of one green beam following the UV illumination can increasingly recover the lasing intensity of the NPRL. The all-optically reversible controllability of the NPRL is basically attributed to the successive UV-beam-induced increase and green-beam-induced decrease in the randomness of the LDDLC via their interactions with the curved cis and rod-like trans isomers after the accumulation of the trans→cis and cis→trans back isomerizations of the azo-dyes, respectively. The former and latter mechanisms can decrease and increase the laser-dye's absorption and thus the induced spontaneous emission, respectively. These consequences can decrease and increase the lasing intensity, or equivalently, increase and decrease the energy threshold for the occurrence of the NPRL, respectively.

Epigallocatechingallate inhibits migration of human uveal melanoma cells via downregulation of matrix metalloproteinase-2 activity and ERK1/2 pathway.

The effects of epigallocatechingallate (EGCG) on the migration and expression of MMP-2 of uveal melanoma cells have not been reported. We studied this effect and relevant signaling pathways in a human uveal melanoma cell line (M17). MTT study found that EGCG did not affect the cell viability of M17 cells up to 100 µM. Wound-healing assay showed that EGCG significantly reduced the migration of melanoma cells in a dose-dependent manner from 20 to 100 µM. Gelatin zymography showed that secreted MMP-2 activity was dose-dependently inhibited by EGCG, whereas the MMP-2 expression at protein and mRNA levels was not affected as determined by western blot and RT-PCR analysis. EGCG significantly increased the expressions of MMP-2 endogenous inhibitors (TIMP-2 and RECK) in M17 cells. Western blot analysis of MAPK signal pathways showed that EGCG significantly decreased phosphorylated ERK1/2 levels, but not p38 and JNK levels, in melanoma cells. ERK1/2 inhibitors also reduced the migration and activity of MMP-2 in M17 cells. The present study suggested EGCG at nontoxic levels could inhibit migration of melanoma cells via downregulation of activities of secreted MMP-2 through the inhibition of the ERK1/2 phosphorylation. Therefore, EGCG may be a promising agent to be explored for the prevention of metastasis of uveal melanoma.

Pleiotropic role of atorvastatin in regulation of human retinal pigment epithelial cell behaviors in vitro.

Statins, inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, possess pleiotropic effects that have been extended to modulation of various cellular behaviors. This study aimed at examining whether atorvastatin (AVN) modulates cell growth, adhesion, migration, and contraction of cultured human retinal pigment epithelium (RPE) cells. The in vitro effects of AVN on human RPE cells was analyzed in terms of cell proliferation, cell cycle, cell adhesion, migration, and contraction assays. The modulatory effect of AVN on TGF-ß2-triggered signaling was determined by Western blotting detection. AVN at submicromolar dose exhibited no prominent morphological alteration and cytotoxicity, whereas it elicited cytostatic effect at concentrations higher than 1 µM. Cell cycle analysis showed that AVN induced growth arrest in both G1 and G2/M phases. AVN at 1 µM or higher concentrations significantly suppressed RPE cell adhesion. Cell migration and 3D collagen contraction assays showed that AVN significantly suppressed RPE cell migration and contractility, respectively. Mechanistically, AVN treatment transiently up-regulated phosphorylation of Akt, ERK1/2, and p38 MAPK, whereas down-regulated that of JNK1. Intriguingly, AVN pretreatment prominently attenuated the TGF-ß(2)-mediated non-Smad signaling, including Akt, ERK1/2, p38 MAPK, and JNK1 phosphorylation. Besides, it directly reduced constitutive level of myosin regulatory light chain peptide MYL9 and mitigated the TGF-ß(2)-induced phosphorylation of myosin phosphatase-targeting subunit 1, MYPT1. These in vitro findings strongly suggest that AVN possesses pleiotropic function on RPE cells, including anti-proliferation, anti-adhesion, anti-migration as well as anti-contraction. In conclusion, AVN treatment may be considered a useful therapy for proliferative vitreoretinal diseases.

Phototherapeutic keratectomy in treating keratomycosis.

PURPOSE: To evaluate the efficacy of using phototherapeutic keratectomy (PTK) in the treatment of superficial keratomycosis. METHODS: We studied 9 patients with superficial keratomycosis that had infiltrated less than half of the corneal thickness and responded poorly to topical antifungal therapy. Using a 193-nm excimer laser, we performed PTK to try to eradicate the infiltrates and facilitate antifungal therapy. We compared our study group findings with those of a control group made up of 31 cases of keratomycosis, also involving infiltration of less than half of the corneal thickness that had been treated with traditional surgical procedures and topical antifungal agents. RESULTS: Using PTK and short-term antifungal eyedrops, we were able to eradicate keratomycosis without recurrence in all 9 study patients. Much less time was needed to treat the PTK group (12.9 +/- 3.6 days) than the control group (40.8 +/- 26.4 days) (P <0.05). After PTK, the ablated area underwent rapid reepithelialization (average, 3.6 +/- 1.8 days). Final vision ranged from 20/200 to 20/20. The PTK group had an average visual improvement of 2.9 +/- 2.1 lines, which was significantly better than final improvement found in the control group (average, 0.6 +/- 1.7 lines) (P < 0.05). PTK complications included mild corneal haze, astigmatism, and thinning cornea. CONCLUSIONS: Because PTK can shorten treatment time, hasten reepithelialization, and restore reasonably good vision, it can be a valuable therapeutic alternative for superficial keratomycosis, especially in instances in which there is poor response to treatment by topical antifungal agents alone.

Leber's hereditary opric neuropathy: a case report.

Leber's hereditary optic neuropathy (LHON) is a maternally inherited mitochondrial disease that primarily affects the optic nerve, causing bilateral vision loss in juveniles and young adults. A 12-year-old boy had complained of blurred vision in both eyes for more than 1 year. His best-corrected visual acuity was 0.08 in the right eye and 0.1 in the left. Ophthalmologic examination showed bilateral optic disc hyperemia and margin blurring, peripapillary telangiectasis, and a relative afferent pupil defect in his right eye. Fluorescein angiography showed no stain or leakage around the optic disc in the late phase. Visual field analysis showed central scotoma in the left eye and a near-total defect in the right. Upon examination of the patient's mitochondrial DNA, a point mutation at nucleotide position 11778 was found, and the diagnosis of LHON was confirmed. Coenzyme Q10 was used to treat the patient.

Management of pseudophakic retinal detachment with undetectable retinal breaks.

BACKGROUND AND OBJECTIVE: Difficulties encountered during the repair of pseudophakic retinal detachment are related to difficulties in peripheral retinal visualization and identification of retinal breaks. The implication of nonvisualized breaks in patients with pseudophakic retinal detachment is associated with lower rates of surgical success. This report decribes the results of a prospective trial to evaluate the efficacy of both scleral buckling surgery in the treatment of pseudophakic retinal detachment with undetected retinal breaks and pars plana vitrectomy techniques in the management of the cases that redetected after primary buckling surgery. PATIENTS AND METHODS: This study represents 25 cases of pseudophakic retinal detachment with undiagnosed retinal breaks. In each case, we performed a scleral buckling that extended over the circumference of the retinal detachment. Pars plana vitrectomy with internal subretinal fluid drainage and long-term tamponade were performed on 7 patients with uncomplicated recurrent retinal detachments after primary buckling surgery. The mean duration of follow up was 32 months. RESULTS: There were 25 eyes (24.5%) of pseudophakic retinal detachment with undiagnosed retinal breaks represented in our pseudophakic retinal detachment cases. Anatomic success was achieved after the initial scleral buckling surgery in 18 eyes (72%). The overall success rate was 92%. The visual acuity was 20/40 or better in 8 patients (32%), 20/80 to 20/40 in 6 patients (24%), 5/200 to 20/80 in 7 patients (28%), and light perception to hand movement in 4 patients (16%). Complications included vitreous hemorrhage, macular pucker, cystoid macular edema, and hypotony with proliferative vitreoretinopathy. CONCLUSION: Scleral buckling surgery in conjunction with cryotherapy is effective in the initial treatment of pseudophakic retinal detachment with undetectable retinal breaks. Pars plana vitrectomy with internal fluid-gas exchange and long-term tamponade can be used to treat these patients with recurrent retinal detachment after primary buckling surgery to get a higher overall success rate.