Sang-Duck Kim

Reactive Oxygen Species in the Activation of MAP Kinases

There are three well-defined subgroups of mitogen-activated protein kinases (MAPKs): the extracellular signal-regulated kinases (ERKs), the c-Jun N-terminal kinases (JNKs), and the p38 MAPKs. Three subgroups of MAPKs are involved in both cell growth and cell death, and the tight regulation of these pathways, therefore, is paramount in determining cell fate. MAPK pathways have been shown to be activated not only by receptor ligand interactions but also by different stressors placed on the cell. MAPK phosphatases (MKPs) dephosphorylate and deactivate MAPKs. Reactive oxygen species (ROS), such as hydrogen peroxide, have been reported to activate ERKs, JNKs, and p38 MAPKs, but the mechanisms by which ROS can activate these kinases are unclear. Oxidative modifications of MAPK signaling proteins and inactivation and/or degradation of MKPs may provide the plausible mechanisms for activation of MAPK pathways by ROS, which will be reviewed in this chapter.

Primary Pterygium Surgery Using the Inferior Conjunctival Transposition Flap

The authors investigated a surgical method for primary pterygium without adjunctive therapy and devised a technique called the inferior conjunctival transposition flap. The procedure was performed by making a flap of the inferior conjunctiva after excision of the pterygium, and transpositioning it to make a covering for the bare sclera and donor site and a barrier to pterygium tissue. This method has been used on 54 eyes of 50 patients (mean age 47 years, range 18 to 69 years) with primary pterygium. All of these patients were treated by one surgeon. During a follow-up period of 12 to 26 months (mean 20 months), the pterygium recurred in 3 (5.6%) of the 54 eyes. In all other cases good anatomic and cosmetic results were achieved without any serious complications. The authors concluded that the inferior conjunctival transposition flap is an encouraging technique for the treatment of primary pterygium.

Tolerance of patients and postoperative results : Topical anesthesia for strabismus surgery

PURPOSE To assess patient tolerance and the postoperative results of intraoperative adjustment of strabismus surgery under topical anesthesia. METHODS Twenty-four patients with strabismus underwent rectus muscle recession under topical anesthesia without the use of additional systemic analgesics and sedatives. Patient tolerance was estimated according to the sites of procedure. In addition, the angle of strabismus was measured 1 day, 6 weeks, and 1 year postoperatively. RESULTS Of the 24 patients identified (11 men and 13 women; mean age: 24 years), 16 had exotropia, 7 were esotropic, and 1 was hypertropic. During the operation, 17 patients never expressed any pain, and 7 patients complained of discomfort on muscle manipulation. Postoperatively, the success rate was 95.8% (23 patients) the first day after surgery, 79.2% (19 patients) after 6 weeks, and 70.8% (17 patients) after 1 year. CONCLUSION Intraoperative adjustment performed with the patient under topical anesthesia is recommended in all cooperative cases of strabismus surgery and is comfortable for patients.

Visualization of retinal and choroidal blood flow with fluorescein leukocyte angiography in rabbits

Abstract• Purpose: To visualize the retinal and choroidal leukocytes in rabbits with a new technique, fluorescein leukocyte angiography using a scanning laser ophthalmoscope. • Methods: Blood was withdrawn from an ear vein of a rabbit (New Zealand White), mixed with fluorescein dye in a test tube and centrifuged. The yellow-brown coat layer containing fluorescein-stained leukocytes was collected and injected into the ear vein of the same rabbit while performing fluorescein angiography with a scanning laser ophthalmoscope. The angiographic image displaying circulating fluorescent leukocytes in retinal and choroidal vessels was recorded on a videotape. • Results: Fluorescent leukocytes were clearly visible in the retinal arteries, capillaries, veins and choroidal vessels for more than 1 h. Plugging of leukocytes was seen throughout this period of time in choroidal vessels, while plugging was rare in retinal vessels. • Conclusions: Fluorescein leukocyte angiography is a new technique which can be used for visualization of the leukocytes in retinal and choroidal vessels non-invasively and in vivo.

Obesity as a Potential Risk Factor for Blepharoptosis: The Korea National Health and Nutrition Examination Survey 2008-2010

Purpose To examine obesity parameters as potential risk factors associated with blepharoptosis in a representative Korean population. Methods We analyzed the Korea National Health and Nutrition Examination Survey (KNHANES), conducted between 2008 and 2010. 10,285 Korean adults (4,441 men and 5,844 women) aged 40 years or older was enrolled. We compared body mass index (BMI), waist circumference (WC) and percentage body fat (BF), according to the severity of blepharoptosis. Multiple logistic regression analysis was conducted to examine the associations of each obesity parameter with blepharoptosis. Results The overall prevalence of age-related blepharoptosis was 14.8 % in South Korea. There were significant and graded associations between increasing blepharoptosis severity and the mean value of obesity parameters (P for trend < 0.05). As marginal reflex distance 1 (MRD1) decreased, the prevalence of general obesity and overweight status increased (P for trend=0.121 in men and < 0.001 in women); the prevalence of abdominal obesity increased (P for trend < 0.001 for both genders); the prevalence of highest quartile of percentage BF increased (P for trend ≤0.001 for both genders). Blepharoptosis was significantly associated with general obesity in women (adjusted odds ratio (aOR), 2.14; 95% confidence intervals (CI), 1.32-3.47); and with the highest quartile of percentage BF in men (aOR, 2.01; 95% CI, 1.34-2.97) and in women (aOR, 1.52; 95% CI, 1.06-2.3317, after adjusting for age, smoking exercise, drinking alcohol, total energy intake, fat intake, total cholesterol, and high density lipoprotein cholesterol, diabetes, hypertension, and family history of eye disease. Conclusions The etiology of age-related blepharoptosis may be multifactorial and is unclear. Our results suggest that obesity parameters such as BMI, WC and percentage BF might be potential risk factors for age-related blepharoptosis in a representative Korean population.