1.Corneal Flap Thickness according to Suction Time of Microkeratome in Porcine Eye.
Koung Hoon KOOK ; Kyoung Yul SEO ; Moon J KIM ; Eung Kweon KIM
Journal of the Korean Ophthalmological Society 2002;43(7):1133-1137
PURPOSE: The purpose of this study is to investigate the effect of the suction time in forming the corneal flap with microkeratome on the corneal flap thickness. METHODS: Thirty porcine eyes were randomly assigned into 3 groups according to suction duration: group 1(10 sec), group 2(35 sec) and group 3(60 sec). The Hansatome microkeratome with 160 plate and a suction ring with 8.5mm diameter were used to create corneal flap. The thickness of central cornea was measured with automated ultrasound pachymeter before the procedure. And after making the flap, the remained corneal thickness was measured with the same method. Then, the difference between the two values was thought to be the corneal flap thickness. RESULTS: The mean corneal flap thickness in group1, 2, and 3 were 91.0+/-24.1 micromiter, 110.1+/-8.9 mu m and 127.2+/-6.1 mu m, respectively. The difference was significant among the three groups(p=0.010), and the longer suction duration made the flap thicker. CONCLUSIONS: These results suggest that in forming the corneal flap with microkeratome, the suction duration has an effect on the corneal flap thickness and an increase of suction duration makes the flap thicker in porcine eyes.
Cornea
;
Suction*
;
Ultrasonography
2.A Clinical Analysis of Neonatal Surgical Gastrointestinal Diseases in Daegu?Busan Area.
Seung Kook SON ; Jae Hong PARK ; Byung Ho CHOI ; Kwang Hae CHOI ; Kyoung Hoon LEE
Korean Journal of Pediatric Gastroenterology and Nutrition 2004;7(2):179-185
PURPOSE: Perinatal mortality rates have been used as a summary statistic for evaluating child health and medical status. Neonatal mortality rates have decreased over the past 30 years in Korea. To understand the current status of neonatal surgical gastrointestinal diseases in Daegu?Busan area, we have studied about neonatal gastrointestinal diseases with their clinical features, postoperative outcome, and mortality rates. METHODS: A clinical analysis on 202 neonates who underwent neonatal surgery from January 1996 to July 2003 at Pusan National University, Kyungpook National University, Youngnam University, and Daegu Catholic University was carried out. RESULTS: The main diseases of surgical conditions were anorectal malformation (23.8%), atresia/ stenosis of midgut (13.4%) and pyloric stenosis (13.4%). The male to female ratio was 2.8:1. Thirty-five cases (17.0%) had one or more associated anomalies including congenital heart disease, cryptoorchidism, hydronephrosis, and chromosomal anomaly. Twenty cases (10.0%) were diagnosed by antenatal ultrasound. Patients with esophageal atresia had the longest hospitalization for 54.6 days. Postoperative complications occurred in 18 cases (8.9%). The main postoperative complications were wound infection (3.5%) and anastomotic leakage (2.5%). Overall mortality was 5.9%. Diaphragmatic hernia showed the highest mortality rate (37.5%), and esophageal atresia (28.6%) and omphalocele (20.0%) were followed. CONCLUSION: The current status of neonatal surgical gastrointestinal diseases in Daegu?Busan area has improved because the disease categories are various, postoperative complications and mortality rates are decreased.
Anastomotic Leak
;
Busan
;
Child
;
Child Health
;
Constriction, Pathologic
;
Daegu
;
Esophageal Atresia
;
Female
;
Gastrointestinal Diseases*
;
Gyeongsangbuk-do
;
Heart Defects, Congenital
;
Hernia, Diaphragmatic
;
Hernia, Umbilical
;
Hospitalization
;
Humans
;
Hydronephrosis
;
Infant
;
Infant Mortality
;
Infant, Newborn
;
Korea
;
Male
;
Mortality
;
Perinatal Mortality
;
Postoperative Complications
;
Pyloric Stenosis
;
Ultrasonography
;
Wound Infection
3.The Effect of Enucleation in Childhood on Orbital Volumetric Growth.
Kyoung Hoon KOOK ; Jung Bum CHOI ; Mi In ROH ; Sang Yeul LEE
Journal of the Korean Ophthalmological Society 2004;45(11):1790-1798
PURPOSE: To evaluate the effect on the growth rate of orbital volume of those who received enucleation or evisceration with or without implants, according to different sizes and operation periods. METHODS: The subjects comprised 47 patients who had previously undergone evisceration or enucleation. The volumes of both anophthalmic and normal orbit were measured from CT scans of patients and compared. The relationship between the orbital volume growth rate and the operation at young age with different size implants or operation without implants was evaluated. RESULTS: Five groups, divided by age at operation, were evaluated. Four groups comprising under 12 years of age, had a significant delay in orbital volume growth development (p<0.05). Three groups, divided by size of implants, were evaluated and 17 mm or smaller sized orbital implants showed significant orbital volume growth retardation (p<0.05) CONCLUSIONS: The effect of early enucleation on orbital volume growth should be considered in patients younger than 12 years old. Furthermore, during the operation, implants with sizes larger than 18mm should be used to prevent the retardation of orbital volume growth.
Anophthalmos
;
Child
;
Humans
;
Orbit*
;
Orbital Implants
;
Tomography, X-Ray Computed
4.A Clinical Study of Pediatric Myelodysplastic Syndrome: Application of International Prognostic Scoring System and the Review of the Korean Literature.
Hoon KOOK ; Chan Jong KIM ; Weon Sang YOON ; Na Eun RYU ; Kyoung Joong CHUNG ; Tai Ju HWANG
Journal of the Korean Cancer Association 2000;32(1):178-190
PURPOSE: Myelodysplastic syndrome (MDS) in children needs to be elucidated in terms of clinical characteristics, natural history, the most effective treatment and prognostic factors, as the disease is very rare and its definition and classification has not reached a consensus by many physician. This study was aimed to describe the characteristics and the disease courses of Korean children with MDS, and to analyze the usefulness of prognostic scoring systems in the prediction of transformation to acute myelogenous leukemia (AML) and overall survival among subgroups. MATERIALS AND METHODS: Fourteen children with MDS seen at Chonnam University Hospital and additional 59 patients identified by the review of Korean literature were evaluated to define clinical characteristics and disease courses. Kaplan-Meier (K-M) probability of leukemic transformation and overall survival were plotted. FAB subtypes, subgroups by Boumemouth Scoring System (BSS), and International Prognostic Scoring System (IPSS) risk groups were compared to predict transformation to AML and overall survival. RESULTS: The median age of 14 patients was 36.5 months. The sex ratio was 3.7:1 (M: F). The frequency of FAB subtypes in Korea was similar to that of other countries except for higher proportion of RA (37%). K-M 3-yr probability of AML transformation and survival for Korean patients were 54.7%, and 49.8%, respectively. Although FAB system, BMS and IPSS were all capable of discriminating subgroups in the prediction of AML transformation and survival, they did not reach the significant level possibly due to small number of patients assigned to each subgroup. CONCLUSION: The clinical characteristics of Korean children with MDS were not different from those of other countries. This study showed the high rate of AML transformation and poor survival in children with MDS.
Child
;
Classification
;
Consensus
;
Humans
;
Jeollanam-do
;
Korea
;
Leukemia, Myeloid, Acute
;
Myelodysplastic Syndromes*
;
Natural History
;
Prognosis
;
Sex Ratio
5.Ophthalmic Manifestations in Patients With Neurofibromatosis.
Jaesoon BANG ; Hong Seok YANG ; Jae Hong AHN ; Kyoung Hoon KOOK ; Yoon Hee CHANG
Journal of the Korean Ophthalmological Society 2008;49(11):1829-1838
PURPOSE: To report the ophthalmic manifestations of neurofibromatosis in Korea. METHODS: Ophthalmologic examinations were performed from November 2001 to January 2008 for 153 consecutive patients who were diagnosed with neurofibromatosis according to the diagnostic criteria for neurofibromatosis. A retrospective analysis was performed according to the medical records of these 153 patients. RESULTS: Seventy seven out of the 153 patients were men, 76 were women and the mean age was 20.44 +/- 14.34 years old. One hundred twelve were neurofibromatosis type 1 and six were neurofibromatosis type 2. Remained thirty five were segmental neurofibromatosis type 1. Ophthalmic manifestations of the neurofibromatosis type 1 were Lisch nodule (52.68%), high myopia (14.29%), plexiform neurofibroma in the orbit (4.46%), cafe au lait spots (4.46%) and optic glioma (3.58%). In the neurofibromatosis type 2, epiretinal membrane (33.33%) showed highest incidence and posterior subcapsular opacity (16.67%), Lisch nodule (16.67%), optic disc edema (16.67%), and optic nerve glioma (16.67%) were also noted. Lisch nodule (25.71%) was the most common ophthalmic finding in segmental neurofibromatosis type 1. CONCLUSIONS: Lisch nodule, which was the most common manifestation of the neurofibromatosis type 1, was less manifested in our cases compared to the previous reports of western countries. In the neurofibromatosis type 2, epiretinal membrane and posterior subcapsular cataract showed higher incidence than those of other types of neurofibromatosis.
Cafe-au-Lait Spots
;
Cataract
;
Edema
;
Epiretinal Membrane
;
Female
;
Humans
;
Incidence
;
Korea
;
Male
;
Medical Records
;
Myopia
;
Neurofibroma, Plexiform
;
Neurofibromatoses
;
Neurofibromatosis 1
;
Neurofibromatosis 2
;
Optic Nerve Glioma
;
Orbit
;
Retrospective Studies
6.Spinal epidural granulocytic sarcoma preceding acute myelogenous leukemia.
Hoon KOOK ; Tai Ju HWANG ; Kyoung CHOE ; Dong Wook YANG ; Jong Hee NAM ; Chang Soo PARK
Journal of Korean Medical Science 1992;7(3):291-296
A rare case of spinal epidural granulocytic sarcoma (GS) preceding acute myelogenous leukemia is described. A 10-year-old boy presented with lower leg weakness. The initial diagnosis was a histiocytic lymphoma, and he was treated accordingly. No evidence of bone marrow involvement was found at that time. The correct diagnosis of epidural GS was made possible in retrospect by using immunoperoxidase staining for lysozyme fourteen months later when the patient showed the full-blown features of leukemia. This rare tumor should be considered in the differential diagnosis of an epidural mass with cord compression in patients with or even without acute leukemia, because early diagnosis followed by appropriate combined chemotherapy and radiation may obviate surgical intervention and eventually prevent leukemic transformation.
Child
;
Epidural Neoplasms/*complications/pathology
;
Humans
;
Immunoenzyme Techniques
;
Leukemia, Myeloid/*complications/pathology
;
Leukemia, Myeloid, Acute/*complications/pathology
;
Male
;
Neoplasms, Second Primary
7.Sumoylation of histone deacetylase 1 regulates MyoD signaling during myogenesis
Hosouk JOUNG ; Sehee KWON ; Kyoung Hoon KIM ; Yun Gyeong LEE ; Sera SHIN ; Duk Hwa KWON ; Yeong Un LEE ; Taewon KOOK ; Nakwon CHOE ; Jeong Chul KIM ; Young Kook KIM ; Gwang Hyeon EOM ; Hyun KOOK
Experimental & Molecular Medicine 2018;50(1):e427-
Sumoylation, the conjugation of a small ubiquitin-like modifier (SUMO) protein to a target, has diverse cellular effects. However, the functional roles of the SUMO modification during myogenesis have not been fully elucidated. Here, we report that basal sumoylation of histone deacetylase 1 (HDAC1) enhances the deacetylation of MyoD in undifferentiated myoblasts, whereas further sumoylation of HDAC1 contributes to switching its binding partners from MyoD to Rb to induce myocyte differentiation. Differentiation in C2C12 skeletal myoblasts induced new immunoblot bands above HDAC1 that were gradually enhanced during differentiation. Using SUMO inhibitors and sumoylation assays, we showed that the upper band was caused by sumoylation of HDAC1 during differentiation. Basal deacetylase activity was not altered in the SUMO modification-resistant mutant HDAC1 K444/476R (HDAC1 2R). Either differentiation or transfection of SUMO1 increased HDAC1 activity that was attenuated in HDAC1 2R. Furthermore, HDAC1 2R failed to deacetylate MyoD. Binding of HDAC1 to MyoD was attenuated by K444/476R. Binding of HDAC1 to MyoD was gradually reduced after 2 days of differentiation. Transfection of SUMO1 induced dissociation of HDAC1 from MyoD but potentiated its binding to Rb. SUMO1 transfection further attenuated HDAC1-induced inhibition of muscle creatine kinase luciferase activity that was reversed in HDAC1 2R. HDAC1 2R failed to inhibit myogenesis and muscle gene expression. In conclusion, HDAC1 sumoylation plays a dual role in MyoD signaling: enhancement of HDAC1 deacetylation of MyoD in the basally sumoylated state of undifferentiated myoblasts and dissociation of HDAC1 from MyoD during myogenesis.
Creatine Kinase, MM Form
;
Gene Expression
;
Histone Deacetylase 1
;
Histone Deacetylases
;
Histones
;
Luciferases
;
Muscle Cells
;
Muscle Development
;
Myoblasts
;
Myoblasts, Skeletal
;
Sumoylation
;
Transfection
8.Effects of Ketamine on the Ca(2+) Channel and K(+) Channel of the Porcine Coronary Artery.
Jung Kook SUH ; Kyung Hyun KIM ; Woo Jong SHIN ; Jong Hoon YEOM ; Kyo Sang KIM ; Hee Koo YOO ; Kyoung Hun KIM
Korean Journal of Anesthesiology 1997;32(4):504-509
BACKGROUND: Ketamine produces increasing in heart rate and arterial blood pressure, in vivo. However, the direct effects of ketamine itself on the porcine coronary arteries are not well determined. In this study, the direct effects of ketamine on the porcine coronary artery responses to vasoactive agents that operate through Ca2+ channel, K+ channels and endothelium related mechanisms were investigated, in vitro. METHODS: Adult porcine hearts(n=12) were obtained from a slaughter house. Coronary arteries were perfused and dissected with 4oC Krebs solution, and were cut into vessel rings and prepared with and without the endothelium(3~4mm in length). The ring segments were suspended in tissue bath(5ml) filled with Krebs solution at 37oC and bubbled with 95% O2-5% CO2 gas mixture. The effect of ketamine(5 10 5, 10 4, 2 10 4M) on vascular smooth muscle tone caused by Ca2+[voltage operated channel(VOC), receptor operated channel(ROC)] and K+channels(Ca2+activated K+ currents, ATP-sensitive K+ currents) regulation were studied with Ca2+ free solution and K+channel blocker. RESULTS: Ketamine induced vasorelaxation of porcine coronary rings that were precontracted by KCl(50 mM) or acetylcholine(3 10 7M). The changes of vascular tone in endothelium intact and removed group did not show statistical significance. In ketamine pretreated group(Ca2+ free solution), after ketamine pretreatment, the last vascular tone was same as that relaxed by ketamine. The other group that without pretreatment of ketamine, the last vascular tone was same as that precontracted with KCl or acetylcholine. In the TEA pretreated group, the porcine coronary artery relaxation was reversed. However, pretreatment with glybenclamide, the porcine coronary artery relaxation was not reversed. CONCLUSIONS: Ketamine induced vasorelaxation of the porcine coronary artery as concentration relating manner, in vitro. The vasorelaxation induced by ketamine was not associated with endothelium. Furthermore, an antagonism of Ca2+ channels(VOC, ROC) and activation of Ca2+ activated K+ channels may be responsible for the porcine coronary arterial relaxing effect of ketamine.
Acetylcholine
;
Adult
;
Anesthetics
;
Arterial Pressure
;
Arteries
;
Coronary Vessels*
;
Endothelium
;
Glyburide
;
Heart Rate
;
Humans
;
Ion Channels
;
Ketamine*
;
Muscle, Smooth, Vascular
;
Pharmacology
;
Potassium Channels, Calcium-Activated
;
Relaxation
;
Tea
;
Vasodilation
9.Defibrotide Treatment for Hepatic Veno-occlusive Disease after Umbilical Cord Blood Transplantation.
Jun Sun YI ; Hoon KOOK ; Ha Young NOH ; Hee Jo BAEK ; So Youn KIM ; Kyoung Ran SOHN ; Ik Sun CHOI ; Hyun Jin PARK ; Tai Ju HWANG
Korean Journal of Pediatric Hematology-Oncology 2004;11(1):92-96
Veno-occlusive disease (VOD) of the liver is a life-threatening complication occurring early after blood or bone marrow transplantation (BMT). Effective treatment has not been established in case of severe forms of VOD. Defibrotide, a single-stranded polydeoxyribonucleotide, has been used on a compassionate basis in recent clinical trials with promising results. We report here with the first Korean experience of using defibrotide for the treatment of hepatic VOD occurring after unrelated umbilical cord blood transplant in a 2-year-old child with acute lymphoblastic leukemia. Defibrotide was administered for 23 days without any significant side effects with resolution of signs and symptoms of VOD.
Bone Marrow Transplantation
;
Child
;
Child, Preschool
;
Empathy
;
Fetal Blood*
;
Hepatic Veno-Occlusive Disease*
;
Humans
;
Liver
;
Precursor Cell Lymphoblastic Leukemia-Lymphoma
;
Umbilical Cord*
10.Granulocytic Sarcoma in Childhood Acute Myelogenous Leukemia: Clinical Characteristics and Management.
Chan Kyun OH ; Hoon KOOK ; Seok Joo KIM ; Ha Young NOH ; Kyoung Ran SOHN ; Hee Jo BAEK ; Tai Ju HWANG
Korean Journal of Pediatric Hematology-Oncology 2004;11(1):55-61
PURPOSE: Granulocytic sarcoma (GS), an extramedullary tumor consisting of primitive myeloid cells, is a rare manifestation of acute myelogenous leukemia (AML). However, GS can occasionally precede the development of systemic leukemia by weeks to years. The objectives of this study are to describe the frequency, clinical characteristics and survival of AML children with GS from a single Korean institute. METHODS: Retrospective review of all the AML children who presented between January, 1995 and June, 2003 was undertaken. RESULTS: GS developed in 9 children among 118 AML patients (incidence, 7.6%). The median age at diagnosis of AML was 82 months (8 months~13 years) with equal sexual distribution. The sites of GS were scalp (n=4), skull (n=3), paranasal sinuses (n=1), external auditory canal (n=1), spinal epidura (n=1), and spinal intramedulla (n=1). The symptoms related with GS were scalp mass (n=4), paraparesis (n=3), facial nerve palsy (n=3), hearing impairment (n=2), and exophthalmos (n=1). In the case with spinal epidural mass, GS preceded the diagnosis of AML by 15 months. Cytogenetics were available in 8 cases, and t (8; 21) was found in five cases. All cases received systemic chemotherapy, with surgical decompression and radiotherapy for 2 patients involving spine. Seven cases received stem cell transplantations (3, allogeneic bone marrow; 4, autologous peripheral blood). The 5-yr event-free survival was 35.0% by Kaplan-Meier method. All 3 allografted patients are alive (86 mo, 5 mo, 1 mo), while 3 of 4 autografted patients had either died or relapsed. CONCLUSION: GS should be considered in patients with or even without AML who have palpable mass or neurological manifestation. Effective treatment, including allogeneic stem cell transplantation, should be considered to achieve a durable disease control.
Allografts
;
Autografts
;
Bone Marrow
;
Child
;
Cytogenetics
;
Decompression, Surgical
;
Diagnosis
;
Disease-Free Survival
;
Drug Therapy
;
Ear Canal
;
Exophthalmos
;
Facial Nerve
;
Hearing Loss
;
Humans
;
Leukemia
;
Leukemia, Myeloid, Acute*
;
Myeloid Cells
;
Neurologic Manifestations
;
Paralysis
;
Paranasal Sinuses
;
Paraparesis
;
Radiotherapy
;
Retrospective Studies
;
Sarcoma, Myeloid*
;
Scalp
;
Skull
;
Spine
;
Stem Cell Transplantation