1.Molecular Mechanism of GnRH Interaction with GnRH Receptor in an Evolutionary Viewpoint.
Jae Young SEONG ; Hyuk Bang KWON
Journal of Korean Society of Endocrinology 2000;15(6):779-790
No Abstract Available.
Gonadotropin-Releasing Hormone*
;
Receptors, LHRH*
2.The effect of Er:YAG laser irradiation on the surface microstructure and roughness of TiO2 implant.
Jang Hyuk AN ; Young Hyuk KWON ; Joon Bong PARK ; Yeek HERR ; Jong Hyuk CHUNG
The Journal of the Korean Academy of Periodontology 2008;38(1):67-74
PURPOSE: The aim of this study was to evaluate the effect of Er:YAG laser on microstructure and roughness of TiO2 blasting implant surface. MATERIALS AND METHODS: Ten TiO2 blasting implant were used in this experiment. One implant was control group, and nine TiO2 blasting implant surfaces were irradiated with Er:YAG laser under 100 mJ/pulse, 140 mJ/pulse, and 180 mJ/pulse condition for 1 min, 1.5 min, and 2 min respectively. Optical interferometer and scanning electron microscopy was utilized to measure roughness and microstructure of specimens. RESULTS: The surface roughness was decreased after Er:YAG laser irradiation in all groups, but there was no significant difference. 100 mJ/pulse and 140 mJ/pulse group did not alter the TiO2 blasting implant surface in SEM study while 180 mJ/pulse group altered the TiO2 blasting implant surface. Implant surfaces showed melting, microfracture and smooth surface in 180 mJ/pulse group. CONCLUSION: Detoxification of implant surface using Er:YAG laser must be irradiated with proper energy output and irradiation time to prevent implant surface alteration.
Freezing
;
Microscopy, Electron, Scanning
3.I-shaped incisions for papilla reconstruction in second stage implant surgery.
Eun Kwon LEE ; Yeek HERR ; Young Hyuk KWON ; Seung Il SHIN ; Dong Yeol LEE ; Jong Hyuk CHUNG
Journal of Periodontal & Implant Science 2010;40(3):139-143
PURPOSE: Pink gingival esthetic especially on the anterior teeth has been an important success criterion in implant-supported restoration. Inter-implant papillae are a critical factor for implant esthetics, and various techniques for inter-implant papilla reconstruction have been introduced. The aim of this study is to suggest and evaluate a surgical technique for reconstructing inter-implant papillae. METHODS: A 28-year-old man had an implant placed on the #13 and #14 area. Four months after implant placement, a second stage surgery was planned for inter-implant papilla reconstruction. At the time of the abutment connection, I-type incisions were performed on the #13i & #14i area followed by full-thickness flap elevation and connection of a healing abutment on underlying fixtures without suture. RESULTS: Two weeks after the second stage implant surgery, soft tissue augmentation between the two implants was achieved. CONCLUSIONS: I-shaped incisions for papilla reconstruction performed during the second stage implant surgery were useful for inter-implant papilla reconstruction and showed a good esthetic result.
Adult
;
Dental Implants
;
Dental Papilla
;
Esthetics
;
Esthetics, Dental
;
Humans
;
Sutures
;
Tooth
4.MRI Study about the Early Changes of Lumbar Disk Degeneration using Magnetization Transfer Contrast (MTC).
Young Soo KIM ; Tae Sub CHUNG ; Tae Hoon KIM ; Eun Kee JEONG ; Hyuk Woo KWON
Journal of the Korean Radiological Society 1995;32(6):865-870
PURPOSE: To obtain magnetization transfer ratio(MTR) of the annulus fibrosus and nucleus pulposus and to assess the feasibility of utilizing the changes of these MTRs as an early indicator of disk degeneration. MATERIALS AND METHODS: MR images of lumbar spine with magnetization transfer(MT) technique in 42 patients were obtained. spin echo techniques (600/14) with same TR/TE with 1KHz off-resonance saturation were employed in 1.0T MR system. MTRs were calculated in two regions, anterior annulus fibrosus and nucleus pulposus, and the results were compared between the normal and degenerative disks, from grade I to IV, on T2-weighted images. RESULTS: MTRs of the nucleus pulposus were 17.6% in the normal disks, and 26.7%, 28.4%, 29.1%, 29.7% in degenerative disks, from grade I to IV, respectively, with a significant difference(P<0.05). On the other hand, MTRs in the annulus fibrosus were 30.2% in the normal disks and 31.5%, 33.2%, 32.1% and 35.6% in degenerative disks, from grade I to IV, respectively, without significant difference. CONCLUSION: Since MTRs are significantly higher in degenerative nucleus pulposus than those of the normal disks, increased MTRs in the nucleus pulposus can be used as an early sign of the degeneration of the nucleus pulposus.
Hand
;
Humans
;
Intervertebral Disc Degeneration*
;
Magnetic Resonance Imaging*
;
Spine
5.Electron microscopy of the oocyte-cumulus complex and immuncytochemistry on the distribution of fibronectin, tenascin, and laminin.
Yu Il LEE ; Ju Eun CHO ; Hyun Jeong PARK ; Young Sook KWON ; Jae Hyuk LEE
Korean Journal of Obstetrics and Gynecology 2000;43(2):192-202
OBJECTIVE: Immunofluorescence microscopy including confocal laser scanning microscopy and electron microscopy were used to study the production of fibronectin, tenascin, and laminin in the cumulus-corona (CC) cells surrounding mature, unfertilized oocytes after ovulation in view of their presumptive importance in the coordination of the processes leading to fertilization and early embryo cleavage, including the final maturation of the ovum, the sperm-egg interaction, and the complex biochemical mechanism between the ovum and the oviduct. METHODS: Mature oocyte-cumulus complex (OCC) was cultured for 24 and 48 hour and fixed in 3.7% formaldehyde. Specimens were incubated with a mixture of primary monoclonal antibodies recognizing different epitopes of fibronectin, tenascin, and laminin, and then with a mixture of secondary antibodies containing FITC, TRITC, and Cy-5 conjugated antibodies. Observation was made by confocal laser scanning microscope equipped with epifluorescece optics. Transmission electron microscopy were used to observe the OCC at 24 and 48 hours after cultrue. RESULTS: The immunocytochemical date demonstrated that CC masses are capable of producing fibronectin and tenascin but their production is heterogeneous in the CC population. Immunoreactivity to fibronectin and tenascin was shown mostly by inner corona cells, and the intensity of immunofluorescence decreased from the central corona cells to the peripheral cumulus cells. Colocalization of fibronectin and tenascin was evident in most CC cells. Moreover, fibronectin and tenascin immunoreactive material was observed in the intracytoplasmic areas, at the plasma membrane level as well as in the extracellular matrix. Whereas, laminin immunofluorescence was found around plasma membrane and extracellular area, but a intracytoplasmic reaction was rarely observed. The distribution of laminin immunofluorescence was similar to that of fibronectin and tenascin, but in some cumulus cells, colocalization between them was not found. Ultrastructurally, cumulus cells projected numerous long, thin microvilli into the intercellular area and some micovilli penetrated into zona pellucida. The inner layer of the cumulus mass was loose arrangement of relatively uniform, small cells with widened intercellular spaces, whereas in the outer layer, cumulus cells are rather larger in size and compact arrangement by narrow, irregular spaces. A small and large linear gap junctions were easily found at cell contacts. The cytoplasm of most cells had abundant organelles typical of steroidogenesis: numerous mitochondrias, a well-developed smooth endoplasmic reticulum, electron dense lipid droplets, and bundles of microtubules and microfilaments. Rudimentary disrupted basal lamina along the cytoplasmic border was rarely seen in a few inner conora cells. CONCLUSION: Even though the functional role of these extracellular matrix proteins remains still unclear, it is reasonable to suggest that they are necessary in various steps of the reproductive process. Cumulus cells appears to be a heterogeneous and dynamic system for suitable microenviroment of fertilization. And functional differences between corona and cumulus cells during the oocyte denudation may be accounted for particular distribution of these adhesive proteins and steroidogenesis-related organelles.
Actin Cytoskeleton
;
Adhesives
;
Animals
;
Antibodies
;
Antibodies, Monoclonal
;
Basement Membrane
;
Cell Membrane
;
Cumulus Cells
;
Cytoplasm
;
Embryonic Structures
;
Endoplasmic Reticulum, Smooth
;
Epitopes
;
Extracellular Matrix
;
Extracellular Matrix Proteins
;
Extracellular Space
;
Female
;
Fertilization
;
Fibronectins*
;
Fluorescein-5-isothiocyanate
;
Fluorescent Antibody Technique
;
Formaldehyde
;
Gap Junctions
;
Immunohistochemistry
;
Laminin*
;
Microscopy, Confocal
;
Microscopy, Electron*
;
Microscopy, Electron, Transmission
;
Microscopy, Fluorescence
;
Microtubules
;
Microvilli
;
Mitochondria
;
Oocytes
;
Organelles
;
Oviducts
;
Ovulation
;
Ovum
;
Sperm-Ovum Interactions
;
Tenascin*
;
Zona Pellucida
6.A case of congenital tuberculosis.
Mee Hye KIM ; Hyuk Choul KWON ; Young Il PARK ; Sang Woo KIM
Journal of the Korean Pediatric Society 1985;28(2):169-173
No abstract available.
Tuberculosis*
7.Clinical study of interlocking intramedullary nailing on proximal or distal femur and distal tibia fracture.
Kwang Yun SEO ; Chil Soo KWON ; Young Wook KIM ; Jin Hyuk KIM ; Mong Lyog SHIN
The Journal of the Korean Orthopaedic Association 1992;27(3):678-685
No abstract available.
Femur*
;
Fracture Fixation, Intramedullary*
;
Tibia*
8.A Case of Antipsychotic-Regression Syndrome in Haloperidol Treated Tourette's Syndrome.
Hee Yeon JEONG ; Hyun Ju CHO ; Young Joon KWON ; In Joon PARK ; Hyuk Hee JIN
Journal of the Korean Society of Biological Psychiatry 1998;5(1):134-137
Authors report a case of separation anxiety disorder, which developed as a side effect during haloperidol treatment of Tourette syndromes(TS). In this case, 14 years old boys developed attention deficit symptoms during his infancy. At 4th grade of primary school, he developed vocal tic, motor tic, and coprolalia. With 5mg/day of haloperidol treatment his symptoms of TS were subsided. During the treatment, he developed features of separation anxiety disorder, including dependence, pleading, clinging, and sadness. Symptoms of attention deficit and separation anxiety disorder were improved by 25mg/day of imipramine treatment. During haloperidol treatment of TS, careful observation may be needed whether separation anxiety disorder-like symptom develops.
Adolescent
;
Anxiety, Separation
;
Haloperidol*
;
Humans
;
Imipramine
;
Tics
;
Tourette Syndrome*
9.Exophytic bone formation using porous titanium membrane combined with pins in rabbit calvarium.
Young KIM ; Young Hyuk KWON ; Joon Bong PARK ; Yeek HERR ; Jong Hyuk CHUNG
The Journal of the Korean Academy of Periodontology 2006;36(2):273-288
The purpose of this study was to evaluate exophytically vertical bone formation in rabbit calvaria by the concept of guided bone regeneration with a custom-made porous titanium membrane combined with bone graft materials. For this purpose, a total of 12 rabbits were used, and decorticated calvaria were created with round carbide bur to promote bleeding and blood clot formation in the wound area. Porous titanium membranes (0.5 mm in pore diameter, 10 mm in one side, 2 mm in inner height) were placed on the decorticated calvaria, fixed with metal pins and covered with full-thickness flap. Experimental group I was treated as titanium membrane only. Experimental group II,III,IV was treated as titanium membrane with BBM, titanium membrane with DFDB and titanium membrane with FDB. The animals were sacrificed at 8 and 12 weeks after surgery, and new bone formation was assessed by histomorphometric as well as statistical analysis. 1. Porous titanium membrane was biocompatable and capable of maintaining the regeneration space. 2. At 8 and 12 weeks, all groups demonstrated exophytic bone formation and there was a statistical significant difference among different groups only at 12 weeks. 3. The DFDB group revealed the most new bone formation compared to other groups (p<0.05). 4. At 12 weeks, DFDB and FDB groups showed the most significant resorption of graft materials (p<0.05). 5. The BBM was not resorbed at all until 12 weeks. 6. The fixation metal pin revealed excellent effect in peripheral sealing. On the basis of these findings, we conclude that a porous titanium membrane may be used as an augmentation membrane for guided bone regeneration, and DFDB as an effective bone forming graft material. The fixation of the membrane with pin will be helpful in GBR technique. However, further study is required to examine their efficacy in the intraoral experiments.
Rabbits
;
Animals
10.Micromorphometric change of implant surface conditioned with Tetracycline-HCl: HA and Etched surface.
Ju Young HAN ; Joon Bong PARK ; Young Hyuk KWON ; Yeek HERR ; Jong Hyuk CHUNG
The Journal of the Korean Academy of Periodontology 2006;36(3):731-744
The present study was performed to evaluate the effect of tetracycline-HCl on the change of implant surface microstructure according to application time. Implant with pure titanium machined surface, HA-coated surface and dual acid etched surface were utilized. Implant surface was rubbed with 50mg/ml tetracycline-HCL solution for 1/2min., 1min., 1 1/2min., 2min., and 2 1/2min. respectively in the test group. Then, specimens were processed for scanning electron microscopic observation. The results of this study were as follows. 1. Both test and control group showed a few shallow grooves and ridges in pure titanium machined surface implants. There were not significant differences between two groups. 2. In HA-coated surfaces, round particles were deposited irregularly. The roughness of surfaces conditioned with tetracycline-HCL was lessened and the cracks were increased relative to the application time. 3. The etched surfaces showed the honey comb structures. The surface conditioning with tetracycline-HCl didn't influence on its micro-morphology. In conclusion, the detoxification with 50mg/ml tetracycline-HCl must be applied respectively with different time according to various implant surfaces.
Animals
;
Comb and Wattles
;
Honey
;
Titanium