Publications by authors named "Duco Hamasaki"

Purpose: High oxygen consumption and cyclical changes related to dark-adaptation are characteristic of the outer retina. Oxygenation changes may contribute to the selective vulnerability of the retina in retinitis pigmentosa (RP) patients, especially for those forms involving genes with global cellular functions. Genes coding for components of the U4/U6.

View Article and Find Full Text PDF

Wolfram syndrome (WFS1, OMIM 222300) is a rare genetic disorder associated with multiple organ abnormalities, most prominently optic nerve atrophy and diabetes. Mutations in the WFS1 gene coding for wolframin have been identified. The pathogenesis for optic nerve atrophy remains elusive.

View Article and Find Full Text PDF

Bilateral common carotid artery occlusion (BCCAO) produces moderate levels of ischemia in the retina of rats, which may simulate the inflow disturbances in severe carotid artery disease. ERG changes following acute BCCAO have been well described, but the effects of chronic BCCAO on the histopathology of the retina remain to be characterized in a reproducible model. Chronic BCCAO was induced in halothane-anaesthetized male Wistar rats and the retina fixed after 3, 6, or 24 hr, 1 week, and 2, 4, or 6 months.

View Article and Find Full Text PDF

The effects of oligemia (moderate ischemia) on the brain need to be explored because of the potential role of subtle microvascular changes in vascular cognitive impairment and dementia. Chronic bilateral common carotid artery occlusion (BCCAO) in adult rats has been used to study effects of oligemia (hypoperfusion) using neuropathological and neurochemical analysis as well as behavioral tests. In this study, BCCAO was induced for 1 week, or 2, 4, and 6 months.

View Article and Find Full Text PDF

Severe visual loss in patients with age-related macular degeneration is associated with the development of choroidal neovascularization (CNV). The pathogenic mechanisms for CNV formation have been extensively investigated, but remarkably little research has addressed the mechanisms for dysfunction of the retina in CNV. Using laser-induced CNV in mice, we evaluated the mechanisms of retinal dysfunction.

View Article and Find Full Text PDF

To investigate the potential of transscleral coulomb-controlled iontophoresis (CCI) for repetitive delivery of acetylsalicylic acid (ASA) into the eye, a total of 50 rabbits was included in this study. Fourteen animals received serial CCI treatment. Fourteen animals underwent CCI with either ASA or balanced salt solution (BSS) for at least 6 days at 24- and 48-hour intervals.

View Article and Find Full Text PDF