We have attempted to measure parafoveal retinal acuity directly on the exact retinal locus, while observing the retinal image in real time using the scanning laser ophthalmoscope(SLO 101, Rodenstock, Munish, Germany). By the SLO Visumetry software(Rodenstock v. 3.0), thirty eyes of healthy volunteers were examined in 20degrees image field. Using Snellen E as stimulus, the examination was performed from the fovea by the radial pattern. The maximal retinal distance point, which responded to stimulus, was recorded by the pixel, and the distance(mm) from the fovea was calculated by the Bennett formula. The maximum distance from the fovea at the given stimulus size was achieved as follows: 0.32+/-0.01mmat the 15 x15 arc of minute(0.333), 0.63+/-0.01mm at the 17 x17 arc of minute(0.294), 1.05+/-0.03 mmat 20 x 20 arc of minute(0.25), and 1.44+/-0.0 5 mmat the 23 x23 arc of minute(0.217). It was also revealed that the horizontal maximal distance from fovea at given stimulus size was statistically superior to the vertical maximal distance(p<0.05). In conclusion we were able to establish the normal range of parafoveal retinal acuity in healthy volunteers. It may serve as the baseline for subsequent study of retinal pathology and functional evaluation as well as its treatment.
Healthy Volunteers* ; Pathology ; Reference Values ; Retinaldehyde* ; Visual Acuity*

No abstract available.
Pericardial Effusion* ; Radionuclide Imaging* ; Technetium Tc 99m Medronate*

The function of ascorbic acid in the eye is unknown. It acts mainly as antioxidant, protecting ocular tissue from oxygen free radical released by light. The concentration of ascorbic acid in the aqueous humor of diurnal mammals is considerably higher than its concentration in the plasma. But the exact concentration of ascorbic acid in the vitreous is unknown. We determined the ascorbic acid concentration in serum, aqueous humor and vitreous of the rabbit using High Performance Liquid Chromatography. The concentration of ascorbic acid is 146.8+/-78.0microgram/ml in aqueous humor, and 58.2+/-25.8microgram/ml(R=0.992) in vitreous. There was significant correlation betweenthe concentration of ascorbic acid in the aqueous humor and vitreous from the same eye. And the inter-indivudual difference of ascorbic acid concntration is greater than the inter-cular difference of ascorbic acid concentration. Therefore it probably due to an active secretion and diffusion into posteror aqueous & vitrous.
Aqueous Humor ; Ascorbic Acid* ; Chromatography, Liquid ; Diffusion ; Mammals ; Oxygen ; Plasma ; Vitreous Body*

PURPOSE: Metallothionein is an intracellular cystein-rich thiol-containing protein. Increased metallothionein content in tumor cells has been suggested to be a mechanism of resistance to cisplatin. In most of previous studies evaluating the role of metallothionein in cisplatin resistance, tumor cells were usually exposed to cadmium to increase metallothionein content. Therefore, cisplatin resistance of the cells may be related to cadmium exposure itself, which induces various changes in cell characteristics, but not to increased metallothionein content. The purpose of this study is to evaluate the role of metallothionein content alone in cellular resistance to cisplatin without exposure of cells to cadmium. MATERIALS AND METHOD: We measured the toxicity of cisplatin in mouse NIH/3T3 cells that vary in their content of metallothionein as a consequence of transfection with a plasmid that result in the constitutive expression of metallothionein. MT cells were derived from NIH/3T3 cells by transfection with a plasmid containing the genome of bovine papilloma virus and the mouse metallothionein-I, derived by the promoter for the glucose-regulated protein of 78kD. Control cells were similary transfected with bovine papilloma virus-based plasmids with the gene for metallothionein inverted and thus separated from the promoter (TM), or deleted, along with promoter (BPA). The number of copies of the plasmid were similar in each kind of transfected cells. Expression of metallothionein required neither selection nor maintenance of cells in the presence of heavy metals. RESULTS: Synthesis of metallothionein was 15-fold greater in the MT cells than in the TM or BPA cells. The concentration of cisplatin sufficient to reduce the cells per well by one-half (IC-50) was 0.40+/-0.075 uM in MT cells. In TM and BPA cells, it was 0.36 0.035 uM and 0.423+/-0.032 uM. There were no significant differences in IC-50 between three cell lines. CONCLUSION: In spite of large differences between MT and control cells in their cellular content of metallothionein, no differences in resistance to cisplatin were observed.
Animals ; Cadmium ; Cell Line ; Cisplatin* ; Genome ; Metallothionein* ; Metals, Heavy ; Mice* ; Papilloma ; Plasmids ; Transfection

PURPOSE: The morphogenic mechanism of tetralogy of Fallot is known to be an antero-superior deviation and hypertrophy of the subpulmonary infundibulum. We performed this study to measure the subpulmonary infundibulum in patients with tetralogy of Fallot and compare those with normal control. METHODS: Echocardiographic data and medical reports of 12 patients, with classical tetralogy of Fa11ot who were diagnosed echocardiographically from Dec. 1996 to Jan. 1999 in Kyungpook National University Hospital, were retrospectively reviewed. A control group consisted of 11 children who underwent a complete echocardiographic examination for a heart murmur and were found to be structually norrnal. Measurements of the subpulmonary infundibulum were performed in systolic still frames with the subxiphoid short axis view. RESULTS: Compared with the normal control children, the following indexed infundibular dimensions in patients with tetralogy of Fallot were significantly smaller' volume, length, cross-sectional area, diameters of pulmonary valve annulus, main, left and right pulmonary arteries, PA index and McGoon ratio. The following measurements were increased in tetralogy patients ' the angle between infundibular septum and ventricular septum, and infundibular free wall thickness. CONCLUSION: We confirmed both antero-superior deviation of infundibular septum and infundibular hypoplasia as morphologic abnormalities in tetralogy of Fallot. We also revealed relatively equal contributions of shortening of infundibular length, and increased infundibular septal and free wall thickness to infundibular hypoplasia.
Axis, Cervical Vertebra ; Child ; Echocardiography ; Gyeongsangbuk-do ; Heart Murmurs ; Humans ; Hypertrophy ; Pulmonary Artery ; Pulmonary Valve ; Retrospective Studies ; Tetralogy of Fallot* ; Ventricular Septum

Inspite of technical advances, the need for pharmacologic treatment of proliferative vitreoretinopathy was increased. In order to evaluate the antiproliferative effect of various antimetabolites to the rabbit retinal pigment epithelial cell, we treated cultured rabbit retinal pigment epithelial cell with different concentration of drugs to perform dose inhibition studies. We found that the antimetabolites inhibited the proliferation of rabbit retinal pigment epithelial cell in a dose dependent and a time dependent manner. The drug concentration required for 50% inhibition of cell growth (ID50) were found to be as follows (BCNU; 6.51 mg/L, 5-FU ; 8.94 mg/L, Daunorubicin; 0.03mg/L, Mitomycin-C; 0.26mg/L).
Antimetabolites* ; Daunorubicin ; Epithelial Cells* ; Fluorouracil ; Mitomycin ; Retinaldehyde* ; Vitreoretinopathy, Proliferative

In vitro PVR(Proliferative vitreoretinopathy) models allow identification of factor which may inhibit porliferation and contraction. In this study we evaluated the contraction of collagen matrix by choroidal fibroblast and the inhibition of contraction by antipoliferative drug. Each antiproliferative drug showed inhibition of collagen matrix contraction : Colchicine (0.1microgram/ml), Cytochalacin (0.05microgram/ml), Puromycin(10microgram/ml). Transmission electron microgram of collagen matrices containing colchicine, cytochalacin or puromycin showed no collagen fiber surrounding choroid fibroblast and showed cell destruction. Scanning electron microgram of collagen matrices containing colchicine, cytochalacin and puromycin showed that collagen fibers were well preserved without distortion. Colchicine, cytochalacin and puromycin are effective inhibitor of cell mediated contraction in additon to it`s potent antiproliferative effect wherease Interfereon has no anticontractile effect. The current study present a model to investigate the effect of antiproliferative drug on fibroblast mediated collagen matrix contraction.
Choroid ; Colchicine ; Collagen* ; Fibroblasts ; Interferons ; Puromycin ; Vitreoretinopathy, Proliferative

Perfluorocarbon liquids(PFCL) have been used as an intraoperative tool for repair of complicated retinal detachment with improving surgical results. However, little is known about the potential toxic effect of PFCL that remain in the eye after surgery to anterior segment tissue. In this study we evaluated the effect of this substance on the corneal tissue. Eight rabbits underwent injection of 50 micro l of perfluorodecalin in the anterior chamber of the right eyes. The left eyes were injected with the same amount of balanced salt solution(BSS) as a control. The clinical appearance of the eyes were recorded at three days, one week and two weeks after injection, and histological examination was done two weeks after injection. The differences of intraocular pressure(IOP) between the right and left eyes were not statistically significant at three days, one week and two weeks after injection, and all of right eyes showed inferior bulbar counctival injection for same periods. In the histological examination of cornea exposed to PFCL, the number and the height of endothelial cells were reduced and decreased, respectively. These findings suggested that PFCL may have a toxic effect on the corneal endothelial cells.
Anterior Chamber ; Cornea ; Endothelial Cells ; Rabbits ; Retinal Detachment

Perfluorodecalin, which is one of the perfluorocarbon liquids, is not established safety in use of long-acting intraocular tamponade. Therefore, to determine its safety we injected it alone and combined with silicone oil into the vitreous of vitrectomized eyes. We evaluated the changes of the fundus, electroretinogram, histopathology as light and electron microgragh after lensectomy and vitrectomy in pigmented rabbits periodically. In rabbits replaced with perfluorodecalin alone, fundus showed mild proliferative vitreoretinopathy and micrographs showed the destruction of the inner and outer segments of the photoreceptors. In rabbits replaced with perfluorodecalin and silicone oil, fundus showed more severe proliferative vitreoretinopathy than perfluorodecalin alone and micrographs showed the destruction of the entire retina. In electroretinogram, the amplitude was decreased markedly. So, it is considered that perfluorodecalin was not tolerant in case of longacting intraocular tamponade and also perfluorodecalin combined with silicone oil developed severe proliferative vitreoretinopathy.
Rabbits ; Retina ; Silicone Oils* ; Vitrectomy ; Vitreoretinopathy, Proliferative

To study the isolation and purification and proliferation of the cell in cell culture system, and to develop an improved culture method by a modified cell isolation technique and modified culture medium. The RPE cells were cultured in 3 different mediums: type I(MEM medium with 20% FCS) type II(F-10 medium with 20% FCS) and type III(DMEM medium with 10% FCS, EGF, hydrocortisone, insulin, ethanolamine, phosphoethanolamine, chorea toxin, triiodotyronine, adenine, transferrin and BPE). We compared population doubling(P.D.), population doubling time(P.D.T), morphologic changes and phagocytic activity during a 7week period. Rapid proliferation and high purity of retinal pigment epithelial cells(RPE cells) showed in type III culture medium. Type III culture medium presented the best results in P.D., P.D.T. and cell purification. In type III culture medium, single RPE cells produced about 6 X 10(7) RPE cells in the 7week period and morphology and phagocytic activity were well maintained, when UV-B irradiation at RPE was used to produce melanin, it had no effect, but the RPE cell was inhibited by UV-B irradiation. This improved culture method for RPE cells will provide a good in-vitro model for the studies of biochemistry, cellular function of the RPE cell, as well as its clinical application in eye disease.
Adenine ; Biochemistry ; Cell Culture Techniques ; Cell Separation ; Chorea ; Epidermal Growth Factor ; Epithelial Cells* ; Ethanolamine ; Eye Diseases ; Hydrocortisone ; Insulin ; Melanins ; Retinaldehyde* ; Transferrin