1.Correction of the ear lobe defect.
Chang Gon KWAK ; Chung Hyun CHANG ; Won Yong YANG ; Doo Hyung LEE
Journal of the Korean Society of Plastic and Reconstructive Surgeons 1992;19(4):647-655
No abstract available.
Ear*
2.The Changes of the Retinal Ganglional Cells in the Pressure-induced Ischemic Rabbit Retina.
Tae Kwann PARK ; Won Sub SON ; Hyung Woo KWAK
Journal of the Korean Ophthalmological Society 2001;42(5):772-782
PURPOSE: There were many studies on the distributions of the retinal ganglion cells(RGC) in the experimental model of the retinal ischemia. RGC was known to be more sensitive to the ischemic injury than the other types of the retinal cells. So, we would identify the changes of the retinal ganglion cell morphologies and distribution after the iatrogenic retinal ischemia induced by intraocular pressure(IOP) elevation. METHODS: Eight pigmented and six white rabbits were used and retinal ischemia was induced by increasing IOP higher than 120 mmHg for 60 minutes. Electroretinogram were recorded at 6 days or 13 days, and histologic findings were observed at 7 or 14 days. RESULTS: After 7 days, RGC densities decreased, cytoplasmic staining disappeared, and the intranuclear hyperpigmentation was noted. RGC densities decreased significantly at 14 days. In the vertical retinal section, some flattening of retinal ganglion cell layer and inner plexiform layer was observed. Changes in the cellular morphologies were prominent. CONCLUSIONS: It may be more appropriate to examine both the retinal whole-mount and the vertical tissue section for the estimatation of the changes of retinal ganglion cell layer in the pressure-induced retinal ischemia.
Cytoplasm
;
Ganglion Cysts*
;
Hyperpigmentation
;
Ischemia
;
Models, Theoretical
;
Rabbits
;
Retina*
;
Retinal Ganglion Cells
;
Retinaldehyde*
3.The Neuroprotective Effect of Intravitreal Melatonin Injection in Pressure-induced Retinal Ischemia.
Seung Joon LEE ; Won Sub SON ; Hyung Woo KWAK
Journal of the Korean Ophthalmological Society 2001;42(4):638-646
PURPOSE: The authors sought to determine the neuroprotective effect of melatonin in a model of ischemic injury in rabbit retina. METHODS: Ischemia was induced by high intraocualr pressure. A dose of 100 microgram of melatonin or dimethyl sulfoxide(DMSO) alone was injected intravitreally just after the induction of ischemia. After 7 and 14 days, the neuroprotective effect of melatonin on ischemic retina was examined with light microscope and transmission electron microscope. RESULTS: The authors found reduction of cytoplasm of retinal ganglion cell(RGC), vacuole formation, chromatin condensation and rupture of nuclear membrane in ischemia-injured eyes treated with DMSO alone. But in melatonin treated eyes, we found that RGC layer's thickness and number of RGC reduced and destruction of cytoplasmic organells and nuclear damage were minimal. The partial recovery of wave is noted in melatonin-treated eyes after ischemia induction. CONCLUSIONS: The melatonin(100 microgram) protected the rabbit retina from high intraocular pressure-induced ischemic injury when administered intravitreally. Melatonin may be useful to decrease neuronal damage in the retina as a result of ischemic injury. But further investigations are neccesary to decide effective concentration, route and time of administration.
Chromatin
;
Cytoplasm
;
Dimethyl Sulfoxide
;
Ganglion Cysts
;
Ischemia*
;
Melatonin*
;
Neurons
;
Neuroprotective Agents*
;
Nuclear Envelope
;
Retina
;
Retinaldehyde*
;
Rupture
;
Vacuoles
4.THE EFFECT OF COLLAGEN SUBSTRATE IN CULTURE MEDIUM ON DNA AND PROTEIN SYNTHESIS OF DERMAL FIBROBLASTS.
Jong Won RHIE ; Hyung Gon SHIM ; Jun Hee BYEON ; Sung Il KWAK ; Chong Kun LEE
Journal of the Korean Society of Plastic and Reconstructive Surgeons 1997;24(2):229-236
Collagen is the major component of scar tissue. Considerable progress of fibroblast growth kinetics and of collagen synthesis has been achieved in the past decade. We have been interested in fibroblasts activities as they are expressed by cells cultured in collagen substrate. This study is to examine the effects of collagen substrate and peptide growth factors In culture medium on DNA and protein synthesis of human dermal fibroblasts. Collagen, interleukin-1(IL-1) and transforming growth factor-beta(TGF-beta) were added to fibroblast culture media according to the designed experiment model and DNA and protein synthesis were measured by [3H]-thymidine, [3H]-leucine, and [3H]-proline incorporation method. The morphological features of fibroblasts were observed by light microscope. The results were as follows ; 1) There were significant decreases of DNA and protein synthesis of cultured fibroblasts in the presence of collagen substrate compared with those in Control groups(p<0.01). 2) DNA and protein synthesis were decreased as dose dependant manner of collagen density in culture media. 3) Morphological features of fibroblasts became less stellate and flat, more spindle-like in the presence of collagen. 4) In responsiveness to IL-1, collagen non-treated groups responded to IL-1 but collagen treated groups were unresponsive to IL-1 (P<0.05). 5) Cells In collagen non-treated groups responded to TGF-beta as dose-related manner(P<0.01). Collagen treated groups desponded to TGF-beta but did not show TGF-beta dose-dependant relationship. In Conclusion, collagen substrate in the culture medium could lower the DNA and protein synthesis of fibroblasts. Cells in collagen substrate were unresponsive or less responsive to peptide growth factors than those in non-collagen substrate.
Cicatrix
;
Collagen*
;
Culture Media
;
DNA*
;
Fibroblasts*
;
Humans
;
Intercellular Signaling Peptides and Proteins
;
Interleukin-1
;
Kinetics
;
Transforming Growth Factor beta
5.Effects of middle ear and temporal bone pathology on bone conduction hearing level in chronic otitis media.
Song Ho KANG ; In Young KWAK ; Chul Won PARK ; Hyung Seok LEE ; Kyung Sung AHN ; Kyung TAE
Korean Journal of Otolaryngology - Head and Neck Surgery 1992;35(5):694-701
No abstract available.
Bone Conduction*
;
Ear, Middle*
;
Otitis Media*
;
Otitis*
;
Pathology*
;
Temporal Bone*
6.The Neuroprotective Effect of alpha-phenyl-N-tert-butyl-nitrone (PBN) in the Argon Laser Induced Retinal Ischemia.
Hyung Kyu PARK ; Won Sub SON ; Hyung Woo KWAK
Journal of the Korean Ophthalmological Society 2002;43(3):599-607
PURPOSE: We examined the ability of alpha-phenyl-tert-butyl-nitrone (PBN), an electron spin trapper, to determine the neuroprotective effect in the argon laser induced ischemic rat retina model. METHODS: After ischemic condition of rat retina was induced by argon green laser, PBN was given intraperitoneally at 50 or 100 mg/kg and normal saline was injected to control group. After 24 hours, 48 hours, and 7 days, the neuroprotective effect of PBN was examined by electroretinogram (ERG) and after 7 days, the enucleation of eyes was performed and histologic findings were compared by light microscopy and transmission electron microscopy. RESULTS: We found relatively reduced amplitude of ERG wave in the PBN injected group but not so greatly reduced as in normal saline control group. The retinal ganglion cell (RGC) layer and the number of RGCs were affected by acute ischemic changes but in the group of PBN treatment, the cell membrane was well preserved and vecuoles formation, cytoplasmic destructions, nuclear chromatin condensation were reduced. CONCLUSIONS: Systemic administration of PBN can ameliorate an argon laser induced retinal ischemia. Further investigations are necessary to decide effective dose without toxicity and to find more convenient methods of administrations.
Animals
;
Argon*
;
Cell Membrane
;
Chromatin
;
Cytoplasm
;
Ischemia*
;
Microscopy
;
Microscopy, Electron, Transmission
;
Neuroprotective Agents*
;
Rats
;
Retina
;
Retinal Ganglion Cells
;
Retinaldehyde*
7.A Clinical Study of Vistamycin in Ophthalmology.
Myung Kyoo KO ; Hyung Woo KWAK ; Won Sik YOUN
Journal of the Korean Ophthalmological Society 1977;18(4):415-417
Vistamycin is a new type of aminoglycoside antibiotics and similar to Kanamycin in its antibacterial spectrum. Vistamycin is especially effective in ophthalmic field due to high penetration into the ocular tissue. In this study, the patients were divided into three groups. 1. 13 cases of ocular infectious diseases such as hordeolum and dacryocystitis. They have received intramuscular injections. 2. 32 cases receiving intramuscular injection for prophylaxis of postoperative infection. 3. 5 cases receiving topical application of 1% Vistamycin eye-drops. Group 1 and 2 were treated with intramuscular injection of Vistamycin 1.0 G.per day for 2 to 10 days. The results were summerized as follows: (1) Group 1 showed good response to Vistamycin with about 77% of efficacy rate. (2) None of group 2 developed postoperative infection. (3) The efficacy rate of group 3 was about 80%.
Anti-Bacterial Agents
;
Communicable Diseases
;
Dacryocystitis
;
Hordeolum
;
Humans
;
Injections, Intramuscular
;
Kanamycin
;
Ophthalmology*
8.Two Cases of Eyelid Sebaceous Carcinoma.
Yun Sik YANG ; Ki Chul KWAK ; Hyung Bae MOON
Journal of the Korean Ophthalmological Society 1988;29(1):213-218
Sebaceous carcinoma is a particularly common malignant tumor of the eyelid. Therefore, this lesion is important to ophthalmologist. Recently, there appears to have been an increased incidence or recognition of sebaceous carcinomas of the eyelid, which had been previously believed to be very rare. Frequently mistaken for a recurrent chalazion, invasion by sebaceous carcinoma is frequently enhanced by repeat curettage and forms of therapy that obscure the true diagnosis. This tumor is difficult to completely resect due to intraepithelial widespread, so its prognosis is poor. The authors experienced two cases of sebaceous carcinoma of the eyelid. One was a 57 year old female patient who was treated with surgical resection and the other was a 71 year old male with cervical lymph node metastasis. He was treated with surgical resection, but he rejected radiotherapy.
Aged
;
Chalazion
;
Curettage
;
Diagnosis
;
Eyelids*
;
Female
;
Humans
;
Incidence
;
Lymph Nodes
;
Male
;
Middle Aged
;
Neoplasm Metastasis
;
Prognosis
;
Radiotherapy
9.The Effect of Intravitreal Melatonin on Rabbit Retina.
Do Gyun KIM ; Won Sup SOHN ; Hyung Woo KWAK
Journal of the Korean Ophthalmological Society 2002;43(9):1781-1788
PURPOSE: To investigate the effect of intravitreal melatonin on retina in rabbit. METHODS: In four pigmented rabbit, melatonin was intravitreally injected 100 mu g/0.1 ml, 300 mu g/0.1 ml concentration in left eye, DMSO was injected in right eye as control. we examined gross fundus finding and electroretinogram and then light and electronic microscopic findings at 24 hours and 1 week with both eye. RESULTS: intravitreally melatonin injected eye at 100 mu g/0.1 ml, 300 mu g/0.1 ml concentration and control eye at 1 day and 1 week, significant difference was not shown in gross fundus finding, electroretinogram, light and electronic microscopic finding. Additionally edema, toxic effect change was not found in retina. CONCLUSIONS: Intravitreally injected melatonin has not influenced on retina grossly, histologically, physiologically at 100 mu g/0.1 ml and 300 mu g/0.1 ml concentration. Further study is required about toxic effect of melatonin over 300 mu g/0.1 ml concentration and clinical usefulness of melatonin in retina.
Dimethyl Sulfoxide
;
Edema
;
Intravitreal Injections
;
Melatonin*
;
Retina*
10.Delay of Spontaneous Neutrophil Apoptosis by Vascular Endothelial Growth Factor.
Chang Won JEON ; Hae Young PARK ; Jong Young KWAK ; Hyung Ho KIM
Journal of the Korean Surgical Society 2005;69(4):328-334
PURPOSE: Vascular endothelial growth factor (VEGF) stimulates angiogenesis and vascular permeability. Tissue damage is related to angiogenesis, and induced by a delay in neutrophil apoptosis. This study was performed to investigate the effect of VEGF on the spontaneous neutrophil apoptosis via the activation of VEGFR-1 and phosphorylation of the p38-MAPK pathway. METHODS: Neutrophils were prepared from 10 healthy young donors, cultured for 20 h, and the apoptosis measured by the morphological changes and flow cytometry. The VEGF receptor expression and phosphorylation of mitogen activated protein kinase (MAPK) were measured using a Western blotting method. RESULTS: VEGF dose-dependently delayed the spontaneous neutrophil apoptosis, but this effect was blocked by pre-treatment of the cells with a VEGF receptor antagonist. VEGF increased the phosphorylated forms of the extracellular stress related kinase (Erk) and p38-MAPK. However, the VEGF-induced delay in apoptosis was not affected by the Erk inhibitor, PD98059 but was affected by the p38- MAPK inhibitor, SB203580. The VEGF receptor-1, but not the VEGF receptor-2, was detected in neutrophils, but its level was reduced in cultured neutrophils. CONCLUSION: VEGF delays neutrophil apoptosis through p38- MAPK activation.
Apoptosis*
;
Blotting, Western
;
Capillary Permeability
;
Flow Cytometry
;
Humans
;
Neutrophils*
;
Phosphorylation
;
Phosphotransferases
;
Protein Kinases
;
Receptors, Vascular Endothelial Growth Factor
;
Tissue Donors
;
Vascular Endothelial Growth Factor A*
;
Vascular Endothelial Growth Factor Receptor-1