1.Paradigm shift regarding sinus augmentation.
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2015;41(2):57-58
No abstract available.
2.A case of acute megakaryoblastic leukemia with Down syndrome.
Sung Jin CHANG ; Sung Min SOHN ; Heung Sik KIM ; Chin Moo KANG ; Dong Seok JEON
Journal of the Korean Pediatric Society 1991;34(12):1730-1735
No abstract available.
Down Syndrome*
;
Leukemia, Megakaryoblastic, Acute*
3.The effect of using laser for ceramic bracket bonding of porcelain surfaces.
Korean Journal of Orthodontics 2008;38(4):275-282
OBJECTIVE: The purpose of this study was to investigate the effect of using laser for ceramic bracket bonding of porcelain surfaces and to compare it with conventional treatment of porcelain surfaces. METHODS: Ninety feldspathic porcelain specimens were divided into 9 groups of 10, with each group having different surface treatments performed. Surface treatment groups were orthophosphoric acid, orthophosphoric acid with silane, hydrofluoric acid, hydrofluoric acid with silane, sandblasted, sandblasted with silane, laser etched, laser etched with silane, and glazed surface served as a control group. In the laser etched groups, the specimens were irradiated with 2-watt superpulse carbon dioxide (CO2) laser for 20 seconds. Ceramic brackets were bonded with light-cure composite resin and all specimens were stored in water at 37degrees C for 24 hours. Shear bond strength was determined in megapascals (MPa) by shear test at 1 mm/minute crosshead speed and the failure pattern was assessed. For statistical analysis, one-way ANOVA and tukey test were used. RESULTS: Statistical analysis showed significant differences between the groups. The HFA + S group showed the highest mean shear bond strength (13.92 +/- 1.94 MPa). This was followed by SB + S (10.16 +/- 1.27 MPa), HFA (10.09 +/- 1.07 MPa), L + S (8.25 +/- 1.24 MPa), L (7.86 +/- 0.96 MPa), OFS + S (7.22 +/- 1.09 MPa), SB (3.41 +/- 0.37 MPa), OFA (2.81 +/- 0.37 MPa), G (2,46 +/- 1.36 MPa). Bond failure patterns of HFA and silane groups, except L + S, were cohesive modes in porcelain while adhesive failure was observed in the control group and the rest of the groups. Conclusions : A 2-watt superpulse CO2 laser etching of porcelain surfaces can provide a satisfactory result for porcelain surface treatment for ceramic bracket bonding. Laser irradiation may be an alternative conditioning method for the treatment of porcelain surfaces.
Adhesives
;
Carbon Dioxide
;
Ceramics
;
Dental Porcelain
;
Hydrofluoric Acid
;
Lasers, Gas
;
Phosphoric Acids
;
Water
5.Bacterial Culture Study of the Hip Joint Fluid during Primary Total Hip Arthroplasty.
Chang Dong HAN ; Joon Seok SOHN ; Wahn Sub CHOE ; Joo Hyung YOO
The Journal of the Korean Orthopaedic Association 1998;33(1):18-23
Infection in primary total hip arthroplasty may cause catastrophic results and is the major reason for implant failure. The purpose of this study was to evaluate the utility of the hip joint fluid culture as a method of predicting the possibility of a hip joint infection by calculating the sensitivity, specificity and accuracy. We performed 628 primary total hip arthroplasty and aerobic and anaerobic bacterial cultures for hip joint fluid between January 1989 and June 1996. The hip joint fluid culture was routinely performed to evaluate the utility of the femoral head for bone banking. Thirty-two cases out of the 628 hips showed positive intraoperative culture and 596 cases showed negative intraoperative culture. The isolated organisms from 32 positive cultures were 11 for Staphylococcus aureus, eight for Staphylococcus coagulase negative, seven for Enterococcus, three for E.coli and one each for Enterobacter, Acinetobacter and Pseudomonas. Anaerobic culture was negative in all cases. In the positive intraoperative culture cases, none had delayed infection during the follow-up period. But in the negative intraoperative culture cases, one case had acute infection and two cases had delayed infection. In the case with acute infection, Staphylococcus aureus was isolated and on two cases with delayed infection, Enterococcus and Staphylococcus coagulase negative were isolated, respectively. All 32 positive culture cases were fa~lse positive and 595 negative culture cases were true negative and one negative culture case was fa~lse negative. The sensitivity of the hip joint culture was 0%, the specificity was 94.9% and the accuracy was 0%. The specificity of hip joint fluid culture in primary total hip arthroplasty was high, hut the sensitivity score was zero. Therefore, the hip joint fluid culture should not be used for a routine check of infection status in primary total hip arthroplasty. We recommend the hip joint fluid culture in revision arthroplasty or hips in which infection is clinically suspected.
Acinetobacter
;
Arthroplasty
;
Arthroplasty, Replacement, Hip*
;
Bone Banks
;
Coagulase
;
Enterobacter
;
Enterococcus
;
Follow-Up Studies
;
Head
;
Hip Joint*
;
Hip*
;
Pseudomonas
;
Sensitivity and Specificity
;
Staphylococcus
;
Staphylococcus aureus
6.Clinical utilization of ultrasonic piezoelectric bone surgery during osteotomy
Journal of the Korean Association of Oral and Maxillofacial Surgeons 2019;45(4):173-173
No abstract available.
Osteotomy
;
Ultrasonics
7.Angiotensin-converting enzyme gene polymorphism is not associated with myocardial infarction in Koreans.
The Korean Journal of Physiology and Pharmacology 1998;2(5):645-650
To assess the relationship between angiotensin-converting enzyme (ACE) gene polymorphism and myocardial infarction in Koreans, we recruited 112 healthy, unrelated subjects (mean age 53.4 years) and 104 myocardial infarction survivors (mean age 54.2 years) of both sexes. An insertion/deletion (IID) polymorphism of the ACE gene was typed by polymerase chain reaction. The I allelic frequency of ACE gene in Korean subjects was irrelevant to myocardial infarction (patients, 65%; control subjects 66%), as was true with the D allele. When compared with other populations, the frequency of D allele in Koreans (0.34) was lower than that in Caucasians, and was close to that of other Oriental populations. The data suggest that the ACE gene polymorphism is not an independent genetic risk factor for myocardial infarction in Koreans.
Alleles
;
Asian Continental Ancestry Group
;
Humans
;
Myocardial Infarction*
;
Polymerase Chain Reaction
;
Risk Factors
;
Survivors
8.G protein-coupled receptor signaling in gastrointestinal smooth muscle.
Uy Dong SOHN ; Dong Seok KIM ; Karnam S MURTHY
The Korean Journal of Physiology and Pharmacology 2001;5(4):287-297
Contraction of smooth muscle is initiated by an increase in cytosolic Ca2+ leading to activation of Ca2+/calmodulin-dependnet myosin light chain (MLC) kinase and phosphorylation of MLC. The types of contraction and signaling mechanisms mediating contraction differ depending on the region. The involvement of these different mechanisms varies depending on the source of Ca2+ and the kinetic of Ca2+ mobilization. Ca2+ mobilizing agonists stimulate different phospholipases (PLC-beta, PLD and PLA2) to generate one or more Ca2+ mobilizing messengers (IP3 and AA), and diacylglycerol (DAG), an activator of protein kinase C (PKC). The relative contributions of PLC-beta, PLA2 and PLD to generate second messengers vary greatly between cells and types of contraction. In smooth muscle cell derived form the circular muscle layer of the intestine, preferential hydrolysis of PIP2 and generation of IP3 and IP3-dependent Ca2+ release initiate the contraction. In smooth muscle cells derived from longitudinal muscle layer of the intestine, preferential hydrolysis of PC by PLA2, generation of AA and AA-mediated Ca2+ influx, cADP ribose formation and Ca2+/-induced Ca2+ release initiate the contraction. Sustained contraction, however, in both cell types is mediated by Ca2+/-independent mechanism involving activation of PKC- epsilon by DAG derived form PLD. A functional linkage between G13, RhoA, ROCK, PKC- epsilon, CPI-17 and MLC phosphorylation in sustained contraction has been implicated. Contraction of normal esophageal circular muscle (ESO) in response to acetylcholine (ACh) is linked to M2 muscarinic receptors activating at least three intracellular phospholipases, i.e. phosphatidylcholine-specific phospholipase C (PC-PLC), phospholipase D (PLD) and the high molecular weight (85 kDa) cytosolic phospholipase A2 (cPLA2) to induce phosphatidylcholine (PC) metabolism, production of diacylglycerol (DAG) and arachidonic acid (AA), resulting in activation of a protein kinase C (PKC)-dependent pathway. In contrast, lower esophageal sphincter (LES) contraction induced by maximally effective doses of ACh is mediated by muscarinic M3 receptors, linked to pertussis toxin-insensitive GTP-binding proteins of the Gq/11 type. They activate phospholipase C, which hydrolyzes phosphatidylinositol bisphosphate (PIP2), producing inositol 1, 4, 5-trisphosphate (IP3) and DAG. IP3 causes release of intracellular Ca2+ and formation of a Ca2+/-calmodulin complex, resulting in activation of myosin light chain kinase and contraction through a calmodulin-dependent pathway.
Acetylcholine
;
Arachidonic Acid
;
Cyclic ADP-Ribose
;
Cytosol
;
Esophageal Sphincter, Lower
;
GTP-Binding Proteins
;
Hydrolysis
;
Inositol
;
Intestines
;
Metabolism
;
Molecular Weight
;
Muscle, Smooth*
;
Myocytes, Smooth Muscle
;
Myosin Light Chains
;
Myosin-Light-Chain Kinase
;
Negotiating
;
Phosphatidylcholines
;
Phosphatidylinositols
;
Phospholipase D
;
Phospholipases
;
Phospholipases A2
;
Phosphorylation
;
Phosphotransferases
;
Protein Kinase C
;
Receptor, Muscarinic M3
;
Receptors, Muscarinic
;
Second Messenger Systems
;
Type C Phospholipases
;
Whooping Cough
9.Improved motility in the gastrointestinal tract of a postoperative ileus rat model with ilaprazole
Geon Min KIM ; Hee Ju SOHN ; Won Seok CHOI ; Uy Dong SOHN
The Korean Journal of Physiology and Pharmacology 2021;25(6):507-515
Postoperative ileus (POI), a symptom that occurs after abdominal surgery, reduces gastrointestinal motility. Although its mechanism is unclear, POI symptoms are known to be caused by inflammation 6 to 72 h after surgery. As proton pump inhibitors exhibit protective effect against acute inflammation, the purpose of this study was to determine the effect of ilaprazole on a POI rat model. POI was induced in rats by abdominal surgery. Rats were divided into six groups: control: normal rat + 0.5% CMC-Na, vehicle: POI rat + 0.5% CMC-Na, mosapride: POI rat + mosapride 2 mg/kg, ilaprazole 1 mg/kg: POI rat + ilaprazole 1 mg/kg, ilaprazole 3 mg/kg: POI rat + ilaprazole 3 mg/kg, and ilaprazole 10 mg/kg: POI rat + ilaprazole 10 mg/kg. Gastrointestinal motility was confirmed by measuring gastric emptying (GE) and gastrointestinal transit (GIT). In the small intestine, inflammation was confirmed by measuring TNF-α and IL-1β; oxidative stress was confirmed by SOD, GSH, and MDA levels; and histological changes were observed by H&E staining. Based on the findings, GE and GIT were decreased in the vehicle group and improved in the ilaprazole 10 mg/kg group. In the ilaprazole 10 mg/kg group, TNF-α and IL-1β levels were decreased, SOD and GSH levels were increased, and MDA levels were decreased. Histological damage was also reduced in the ilaprazole-treated groups. These findings suggest that ilaprazole prevents the decrease in gastrointestinal motility, a major symptom of postoperative ileus, and reduces inflammation and oxidative stress.
10.Clinical evaluation of implant retained overdentures using two implant and Locator attachments in the fully edentulous mandibles.
Ju Hyoung LEE ; Dong Seok SOHN
The Journal of Korean Academy of Prosthodontics 2011;49(4):283-290
PURPOSE: This study compared the marginal bone loss around dental implant that were placed in the canine areas of the mandibles and finded the survival rate of implants, marginal bone loss around implants and prosthetic complications in 10 patients treated with overdentures retained with Locator attachments. MATERIALS AND METHODS: Ten patients who had received implant retained overdentures in the mandibules using two implants and Locator attachments at Daegu Catholic University Medical Center from 2004 to 2010 were included in this study. Evaluations of the survival rate of implants, marginal bone loss and prosthetic complications were performed. RESULTS: Implants placed in this study showed a 100% survival rate and the average annual bone loss was 1.03 mm +/- 0.20 mm in the first year. The patients have verbally indicated that they are comfortable and that their overdentures function well. But, implant retained overdentures had various prosthetic complications such as male change, relining, rebasing and denture fracture. CONCLUSION: Implant retained overdentures using two implant and Locator attachments in the fully edentulous mandibles is considered as a stable way for long terms because of minimal invasive operation, simple prosthetic process and easy repair.
Academic Medical Centers
;
Dental Implants
;
Denture, Overlay
;
Dentures
;
Humans
;
Male
;
Mandible
;
Survival Rate