1.THREE-DIMENSIONAL COMPARISON OF FRAMEWORK DISPLACEMENTS JOINED BY VARIOUS CONNECTION TECHNIQUES.
Jang Seop LIM ; Young Chan JEON ; Chang Mo JEONG
The Journal of Korean Academy of Prosthodontics 1999;37(3):358-374
This study measured the relative displacements of the five-unit fixed partial dentures as cast with the same fixed partial dentures sectioned and assembled by investment-soldering, soldering stand-soldering, and cast-joining techniques. A total of fifteen specimens using a type IV gold alloy wee one-piece cast as control and then sectioned and assembled five test specimens for each method were prepared. A computerized three dimensional coordinate measuring machine and specially designed cylinder for this study were used. Displacement was defined by six displacement variables for the each of cylinders incorporated in each casting: three component displacements ( Lx, Ly, and Lz) and rotational displacements( thetax, thetay, thetaz). The global displacement was computed using the mathematical formula R= Global displacement ={{{{rm SQRT { (x'-x)^2 +(y'-y)^2 + (z'-z)^2} }} }} Under the conditions of this study, the following conclusions were drawn: 1. The investment-soldering group showed the largest mean value of final global displacements, followed by stand-soldering group, cast-joining group and one-piece cast group. However, between the mean values of final global displacement for the cast-joining group and one-piece cast group, there was no significant difference. 2. For investment-soldering and stand-soldering groups, the greater global displacements were recorded in soldering phase than in indexing or investing phase. 3. For one-piece cast group, the displacements occured mostly in the casting phase. And for castjoining group, there was no significant difference in global displacements among the fabrication procedures. 4. Intercentroidal distance decreased in framework-pattering, solder-indexing, solder-standing, and soldering phases, but increased in investment block-investing and casting phases. 5. Specially designed cylinder for touch-trigger type coordinate measuring machine was validated.
Abstracting and Indexing as Topic
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Alloys
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Denture, Partial, Fixed
;
Investments
;
Methods
2.Distribution of NPY-immunoreactive neurons in the visual cortex of the cat.
Chang Do CHOI ; Young Gil JEONG ; Wol Bong CHOI
Korean Journal of Anatomy 1993;26(3):258-267
No abstract available.
Animals
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Cats*
;
Neurons*
;
Visual Cortex*
3.Treatment of the Scaphoid Fracture
In KIM ; Seung Koo LEE ; Han CHANG ; Dae Young JEONG
The Journal of the Korean Orthopaedic Association 1988;23(5):1365-1374
Twenty-three cases of the scaphoid fracture which were treated at the Department of the Orthopaedic Surgery, Catholic University Medical College during the period of december 1978 to december 1987 were analysed. The main purpose of this study was to clarify the significant factors affecting the union rate of the scaphoid fracture. The results obtained were as follows ; 1. The great majority of 23 cases was male with mean age 31. 2. Ulnar deviated stress oblique view with msking a fist was the most reliable means for diagnosing the fracture, location of fracture and stability of wrist after scaphoid fracture. 3. Union rate was obtained from 88.8% in undisplaced fresh fracture, 85.7% in displaced fresh fracture and 71.4% in old neglected fracture. 4. The union rate and associated factors affecting the prognosis after scaphoid frscture seems to be depended on the location of fracture, the severity of initial displacement of fracture fragments, time elapsed of treatment after fracture and accompanied injuries around the ipsilateral wrist.
Humans
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Male
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Prognosis
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Wrist
5.Intrathecal Endothelin-1 Reduced the MAC of Isoflurane in the Rat.
Chang Young JEONG ; Woong Mo IM ; Myung Ha YOON ; Sang Do HAN ; Sung Wook JEONG
Korean Journal of Anesthesiology 1997;33(2):215-221
BACKGROUND: Recent evidences suggest that anesthetic action within the spinal cord is important in suppressing somatic responses to painful stimuli. Intrathecal endothelin-1 (ET-1) is known to have antinociceptive effect. The purpose of this experiment was to determine whether intrathecal ET-1 may influence the minimum alveolar concentration (MAC) of isoflurane in rats and access the role of the spinal cord as the sites of anesthetic action in blocking somatic responsiveness. METHODS: In Sprague-Dawley rats fitted with an indwelling intrathecal catheter, we determined the MAC of isoflurane using a tail-clamp technique as a painful stimulus, combined with end-tidal anesthetic sampling. In experiment 1, the control MAC was determined and changes of control MAC were observed after intrathecal ET-1 (4x10-2 nmol, 4x10-3 nmol) administration. In experiment 2, we observed the effects of L or N type Ca++ channel blocker such as verapamil (50 g) or W-conotoxin (0.5 g) on the MAC after measurement of the control MAC. In experiment 3, after measurement of the control MAC, ET-1 (10-2 nmol) was administered intrathecally and the MAC was determined again. Next, intrathecal verapamil (50 g) or W-conotoxin (0.5 g) was injected. After that, the MAC was determined again. RESULTS: In experiment 1, ET-1 decreased the MAC of isoflurane and its effect was sustained over 2 hours. In experiment 2, the MAC, determined following administration of verapamil or W-conotoxin, was not different from that of the control. In experiment 3, the MAC was decreased after ET-1 administration and then increased following injection of verapamil or W-conotoxin. CONCLUSIONS: These results suggested that ET-1, in relation to calcium, might play an important role in determining the MAC of isoflurane in the spinal cord.
Animals
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Calcium
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Catheters
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Endothelin-1*
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Isoflurane*
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Rats*
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Rats, Sprague-Dawley
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Spinal Cord
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Verapamil
6.THE INFLUENCE OF WATTAGE AND CURING TIME OF MICROWAVE ENERGY ON PHYSICAL PROPERTIES OF THE DENTURE BASE RESIN.
Dae Sung JEONG ; Jang Seop LIM ; Chang Mo JEONG ; Young Chan JEON
The Journal of Korean Academy of Prosthodontics 1999;37(6):767-775
The purpose of this study was to evaluate the effect of wattage and curing time on surface hardness, three-point bending strength and internal porosity of microwave curing denture base resin. Two sizes of resin spicimens were made of Acron MC ; 3.5x10x60mm for surface hardness and three-point bending strength measurement and 5x12x60mm for internal porosity measurement. They were cured by microwave energy at varing wattages(500W, 700W) and curing times(2min., 3min., 4min.) to determine if a certain wattage/curing time combination would improve physical properties. Surface hardness was measured with Vikers hardness tester, three-point bend-ing strength with universal testing machine and internal porosity was calculated by measuring the weight in air and in water. The results obtained were as follows : 1. There was no significant difference in percent porosity among experimental groups(p>0.05). 2. 500W/3min, group showed the higher surface hardness than 700W/2, 3, 4min. groups(p<0.05), and 700W/4 min. group showed the lower surface hardness than 500W/2, 3, 4min. groups(p<0.05), but there was no significant difference among others(p>0.05). 3. 500W/3min. group yielded the higher value of bending strength than 500W/2min., 700W/3, 4min. groups(p<0.05), but there was no significant difference among others(p>0.05).
Denture Bases*
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Dentures*
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Hardness
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Hardness Tests
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Microwaves*
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Polymethyl Methacrylate
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Porosity
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Water
7.Myeloid-Derived Suppressor Cells in Inflammatory Bowel Disease.
Yeon Jeong KIM ; Sun Young CHANG ; Hyun Jeong KO
Intestinal Research 2015;13(2):105-111
Immature myeloid cells, also known as myeloid-derived suppressor cells (MDSCs), include neutrophilic and monocytic myeloid cells, and are found in inflammatory loci and secondary lymphoid organs in mice with intestinal inflammation, inflammatory bowel disease (IBD) patients, and tumor tissues. However, the roles of MDSCs in IBD are not yet well understood, and there are controversies regarding their immunosuppressive functions in IBD. In addition, recent studies have suggested that endoplasmic reticulum (ER) stress in intestinal epithelial cells, especially in Paneth cells, is closely associated with the induction of IBD. However, the ER stress in MDSCs accumulated in the inflamed tissues of IBD patients is not yet fully understood. In the current review, we discuss the presence of accumulated MDSCs in the intestines of IBD patients, and further speculate on their physiological roles in the inflammatory condition with interleukin 17-producing cells, including Th17 cells. In particular, we will discuss the divergent functions of MDSCs in ER stressed intestinal environments, including their pro-inflammatory or immunosuppressive roles, based on the consideration of unfolded protein responses initiated in intestinal epithelial cells by ER stress.
Animals
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Endoplasmic Reticulum
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Endoplasmic Reticulum Stress
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Epithelial Cells
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Humans
;
Inflammation
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Inflammatory Bowel Diseases*
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Interleukin-17
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Interleukins
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Intestines
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Mice
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Myeloid Cells
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Neutrophils
;
Paneth Cells
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Th17 Cells
;
Unfolded Protein Response
8.Myeloid-Derived Suppressor Cells in Inflammatory Bowel Disease.
Yeon Jeong KIM ; Sun Young CHANG ; Hyun Jeong KO
Intestinal Research 2015;13(2):105-111
Immature myeloid cells, also known as myeloid-derived suppressor cells (MDSCs), include neutrophilic and monocytic myeloid cells, and are found in inflammatory loci and secondary lymphoid organs in mice with intestinal inflammation, inflammatory bowel disease (IBD) patients, and tumor tissues. However, the roles of MDSCs in IBD are not yet well understood, and there are controversies regarding their immunosuppressive functions in IBD. In addition, recent studies have suggested that endoplasmic reticulum (ER) stress in intestinal epithelial cells, especially in Paneth cells, is closely associated with the induction of IBD. However, the ER stress in MDSCs accumulated in the inflamed tissues of IBD patients is not yet fully understood. In the current review, we discuss the presence of accumulated MDSCs in the intestines of IBD patients, and further speculate on their physiological roles in the inflammatory condition with interleukin 17-producing cells, including Th17 cells. In particular, we will discuss the divergent functions of MDSCs in ER stressed intestinal environments, including their pro-inflammatory or immunosuppressive roles, based on the consideration of unfolded protein responses initiated in intestinal epithelial cells by ER stress.
Animals
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Endoplasmic Reticulum
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Endoplasmic Reticulum Stress
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Epithelial Cells
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Humans
;
Inflammation
;
Inflammatory Bowel Diseases*
;
Interleukin-17
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Interleukins
;
Intestines
;
Mice
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Myeloid Cells
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Neutrophils
;
Paneth Cells
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Th17 Cells
;
Unfolded Protein Response
9.Pagetoid Bowen's Disease on the Dorsum of Foot
Hae Bong JEONG ; Jeong Won JO ; Young Bin SHIN ; Chang Il KWON ; Chi Yeon KIM
Korean Journal of Dermatology 2019;57(3):156-157
No abstract available.
Bowen's Disease
;
Foot
10.COLORIMETRIC ANALYSIS OF COLOR DIFFERENCES BETWEEN DENTIN PORCELAINS.
Chang Seop KIM ; Jang Seop LIM ; Chang Mo JEONG ; Young Chan JEON
The Journal of Korean Academy of Prosthodontics 1999;37(4):425-432
The purpose of this study is to evaluate the color differences that can exist between differnet brands of dentin porcelain having identical shade designations. The instrumental colorimetric technique was used to determine these differences. The three brands of dentin porcelain used were Vita VMK-68, Shofu Vintage, and Ceramco II. The three shades selected were the Vita Lumin shades A2, B2, and C2. The color difference values were compared with each other using L*, a*, b*, three variables of the CIELAB color system, and E. The results of this study were as follows: 1. Corresponding shades of different brands of dentin porcelain produced different L*, a*, b* values. 2. The greatest E value in corresponding shade was found to exist between Ceramco II and Shofu Vintage, followed by between Vita VMK-68 and Ceramco II, and then between Vita VMK-68 and Shofu Vintage. 3. The E values in shade C2 were mainly influenced by L* value ; however none of L*, a*, b* values had greater influence on E values than the others in shade A2, B2. 4. Shofu Vintage had the highest b* value, followed by Vita VMK-68, and then Ceramco II.
Dental Porcelain*
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Dentin*