1.Finite element analysis on the connection types of abutment and fixture.
Byeong Hyeon JUNG ; Gyeong Je LEE ; Dong Wan KANG
The Journal of Korean Academy of Prosthodontics 2012;50(2):119-127
PURPOSE: This study was performed to compare the stress distribution pattern of abutment-fixture connection area using 3-dimensional finite element model analysis when 5 different implant systems which have internal connection. MATERIALS AND METHODS: For the analysis, a finite element model of implant was designed to locate at first molar area. Stress distribution was observed when vertical load of 200 N was applied at several points on the occlusal surfaces of the implants, including center, points 1.5 mm, 3.0 mm away from center and oblique load of 200 N was applied 30degrees inclined to the implant axis. The finite element model was analyzed by using of 3G. Author (PlassoTech, California, USA). RESULTS: The DAS tech implant (internal step with no taper) showed more favorable stress distribution than other internally connected implants. AS compare to the situations when the loading was applied within the boundary of implants and an oblique loading was applied, it showed higher equivalent stress and equivalent elastic strain when the loading was applied beyond the boundary of implants. Regardless of loading condition, the abutments showed higher equivalent stress and equivalent elastic strain than the fixtures. CONCLUSION: When the occlusal contact is afforded, the distribution of stress varies depending on the design of connection area and the location of loading. More favorable stress distribution is expected when the contact load was applied within the diameter of fixtures and the DAS tech implant (internal step with no tapering) has more benefits than the other design of internally connected implants.
4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid
;
Axis, Cervical Vertebra
;
Bite Force
;
California
;
Dental Implants
;
Finite Element Analysis
;
Molar
;
Sprains and Strains
2.Centrilobular Distribution of Ethylnitrosourea-Induced Hepatocellular Foci in the Mouse.
Byoung Hun KIM ; Soong Hwan LEE ; Seong Kyu YANG ; Jong Cheol KIM ; Yeong Jung CHO ; Yong Hyeon JO ; Byeong Moo YOO ; Chul Hun JUNG ; Dong Hoo LEE
The Korean Journal of Hepatology 1997;3(3):227-240
BACKGROUND/AIMS: Hepatocytes on the hepatic lobule mipate from portal zone to centrilobular mea as the DNA synthesis within it. And also, the xenobiotic reactions reveal characteristic differences associated with zone specific metabolism in the liver acinus. In this study, the zonal distribution of ethylnitrosourea (ENU)-induced hepatic precancerous lesion was stereologically investigated. METHODS: Nine B6C3F1 mices were given I.p. injection of ENU (60 ug/pn body weight) when the pups were 15 days old prior to sacrifices at 8 weeks of life. All the 150 consecutive sections, 3 p m in thickness, were stained with hematoxylin and eosin and identified the basophilic precancerous lesions with 80-165 p m diameter in equatorial plane by the Zeiss microprojector. And then the distances from the center of selected foci to terminal hepatic vein or portal vein branches were estimated under the microscopic fields. As a control group, the same estimations were performed from the random points by the appointments of random digit table. RESULTS: Mean distance between ENU-induced 52 hepatocellular foci and the nearest terminal hepytic vein was 181.15+112.39 p m (Mean+ SD), but that of randomly selected 104 points was 291.73+157.98pm (Mean+5D) (Students t-test, p<0.0005). Substantially, 52.7% of ENU-induced 52 hepatocellular foci were within 300 p m from the terminal hepatic vein, but randomly selected 104 points were only 50.9% (Shapiro Wilk W test, w=0.819857, p=0.048038). Mean distance from ENU-induced 52 foci to portal vein was 398.85+149.98pm (Mean+SD), but that from the randomly selected 104 points was 315.87+145.79 pm (Mean+SD)(Students t-test, p<0.0005). CONCLUSION: Stereologically, ENU-induced mice liver cell foci distribute non-randomly to Zone III, centrilobular zone of mouse hepatic acini where promote invasion toward terminal hepatic veins.
Animals
;
Appointments and Schedules
;
Basophils
;
Cholestasis
;
DNA
;
Eosine Yellowish-(YS)
;
Ethylnitrosourea
;
Fluconazole
;
Hematoxylin
;
Hepatic Veins
;
Hepatocytes
;
Liver
;
Metabolism
;
Mice*
;
Portal Vein
;
Veins
3.Comparison between Measured and Calculated Length of Side Branch Ostium in Coronary Bifurcation Lesions with Intravascular Ultrasound.
Hyeon Min RYU ; Byeong Keuk KIM ; Jung Sun KIM ; Young Guk KO ; Donghoon CHOI ; Yangsoo JANG ; Myeong Ki HONG
Yonsei Medical Journal 2012;53(4):680-684
PURPOSE: Accurate evaluation of side branch (SB) ostium could be critical to the treatment of bifurcation lesions. We compared measured and calculated values of side branch ostial length (SBOL) in coronary bifurcation lesions with intravascular ultrasound (IVUS). MATERIALS AND METHODS: Pre-intervention and post-intervention IVUS was performed in 113 patients who underwent stent implantation of bifurcation lesions. For the IVUS longitudinal reconstruction of the bifurcation lesions, SBOL, SB diameter, and the angle between the distal portion of the main vessel (MV) and SB were directly measured. In addition, SBOL was calculated as: SB diameter/sin (angle between distal MV and SB). The relationship between measured and calculated SBOL was then evaluated. RESULTS: The angled between the distal MV and SB were 57.3+/-12.4degrees at pre-intervention and 59.4+/-12.6degrees at post-intervention. The mean measured and calculated SBOL values were 2.91+/-0.86 mm and 3.06+/-0.77 mm at pre-intervention and 2.79+/-0.82 mm and 2.92+/-0.69 mm at post-intervention, respectively. Differences between measured and calculated SBOL were 0.15+/-0.44 mm at pre-intervention and 0.13+/-0.41 mm at post-intervention. We found that calculated SBOL was correlated with measured SBOL (pre-intervention r=0.863, p<0.001; post-intervention r=0.868, p<0.001). CONCLUSION: There was a good correlation between measured and calculated SBOLs of the bifurcation lesions in IVUS longitudinal reconstruction. SBOL in the bifurcation lesions can therefore be estimated using the SB diameter and the angle between distal MV and SB.
Aged
;
Angioplasty, Balloon, Coronary
;
Coronary Angiography
;
Coronary Artery Disease/surgery/*ultrasonography
;
Coronary Vessels/*ultrasonography
;
Female
;
Humans
;
Male
;
Middle Aged
;
Ultrasonography, Interventional
4.Development and Validation of DIS-IV, Korean Version.
Guk Hee SUH ; Hyeon Gyun SON ; Sang Sub CHOI ; Mi Kyung LEE ; Jung Seo YI ; Ihn Geun CHOI ; Hyeon Soog BANG ; Byeong Kil YEON
Journal of Korean Neuropsychiatric Association 2001;40(5):777-788
OBJECTIVE: Appearance of DSM-IV has influenced greatly on the nosological classification of mental disorder, not considered as revised one of DSM-III-R but a new criteria. DIS-IV has been developed after revision of DIS-III in consideration of various changes in DSM-IV. This study is to develop and validate the DIS-IV, Korean version to activate Korean psychiatric research much more and to modivate more frequent international collaborative study. METHOD: Translation committee produced DIS-IV, Korean version through all the procedures of translation, back-translation, confirmation of retained original meaning of the English version, adaptation to Korean linguistic usage and preliminary study. Four medical students were trained during DIS-IV training course that retained the same contents and methods as of Washington University. Inter-rater reliability was measured by comparison between two diagnoses made from two interviewer who rated one patient at the same time. Procedural validity was measured by comparison between lay-interviewer's diagnosis and psychiatrist's diagnosis which were made after independent DIS-IV using interview. Subjects were 124 patients who were being treated at two University Hospital and National Forensic Psychiatric Hospital between January, 2000 and August, 2000. RESULTS: Average kappa value of inter-rater reliability was 0.74. Diagnoses showing over 0.7 in kappa value were bipolar I disorder, generalized anxiety disorder, depressive disorder, obsessive-compulsive disorder, oppositional defiant disorder, pain disorder, pathological gambling, post-traumatic stress disorder, specific phobia and almost all substance use disorder or substance- related disorder. Procedural validity, that compared lay-interviewer's diagnosis and psychiatrist's diagnosis, were as follows;For all diagnoses, sensitivity, specificity and kappa were 67.6%, 98.3% and 0.69. For diagnoses of substance use disorder or substance- related disorder, sensitivity, specificity and kappa were 79%, 98% and 0.77. For other diagnoses except substance use disorder or substance- related disorder, sensitivity, specificity and kappa were 60.5%, 98% and 0.64. This results are almost at the same level as that of Robins and her colleagues who first reported reliability and validity of DIS. CONCLUSION: We think that DIS-IV, Korean version has higher reliability and validity. It is very important that diagnoses of substance use disorder and substance-related disorder can be made reliably and validly by this instrument. We expect that it can help to improve diagnosability of mental disorder, activate clinical research and increase international scientific communication.
Anxiety Disorders
;
Attention Deficit and Disruptive Behavior Disorders
;
Classification
;
Depressive Disorder
;
Diagnosis
;
Diagnostic and Statistical Manual of Mental Disorders
;
Gambling
;
Hospitals, Psychiatric
;
Humans
;
Linguistics
;
Mental Disorders
;
Obsessive-Compulsive Disorder
;
Phobic Disorders
;
Reproducibility of Results
;
Sensitivity and Specificity
;
Somatoform Disorders
;
Songbirds
;
Stress Disorders, Post-Traumatic
;
Students, Medical
;
Substance-Related Disorders
;
Washington
5.A Case of Rheumatoid Arthritis Associated with Renal Amyloidosis and Crescentic Glomerulonephritis.
Jung Hyeon CHOI ; Byeong Kuk IM ; Jun Hyeock CHOI ; Hyeon Kyeong CHO ; Youn Gil CHOI ; Heung Soo KIM ; Gyu Tae SHIN ; Do Hun KIM ; Jae Hoo HAN
Korean Journal of Nephrology 2001;20(6):1058-1063
A case of renal amyloidosis with crescentic glomerulonephritis associated with rheumatoid arthritis is described. A 60-year-old female with 15 years' history of rheumatoid arthritis developed nephrotic syndrome followed by rapid deterioration of renal function. Glomerular amyloid deposition and sclerotic change was present in kidney biopsy specimen and crescentic change was found in 85% of the glomerulus. Electron microscopic finding of glomerulus showed randomly oriented, rigid-appearing, long nonbranching fibrils. The patient was treated with intravenous high-dose methylprednisolone pulses combined with intravenous cyclophosphamide followed by oral corticosteroids. Three months after the above treatment, renal function gradually improved, reaching serum creatinine level to 2.5 mg/dL. But the nephrotic range proteinuria persisted.
Adrenal Cortex Hormones
;
Amyloidosis*
;
Arthritis, Rheumatoid*
;
Biopsy
;
Creatinine
;
Cyclophosphamide
;
Female
;
Glomerulonephritis*
;
Humans
;
Kidney
;
Methylprednisolone
;
Middle Aged
;
Nephrotic Syndrome
;
Plaque, Amyloid
;
Proteinuria
6.A Case of Wegener's Granulomatosis with Thin Glomerular Basement Membrane Disease.
Hak Jin HWANG ; Ju Ik SON ; Jung Sik SONG ; Yong Beom PARK ; Byeong hyun IN ; Soo Kon LEE ; Hyeon Joo JUNG
The Journal of the Korean Rheumatism Association 2001;8(3):192-197
Wegener's granulomatosis is a necrotizing,granulomatous vasculitis that involves multiple organs including the upper and lower respiratory tract and the kidney.The kidney initially exhibits focal necrotizing glomerulonephritis,which progresses to crescentic glomerulonephritis in Wegener's granulomatosis.We experienced a case of Wegener's granulmatosis which was associated with a thin glomerular basement membrane disease.The patient suffered from nasal stuffiness,recurrent serous otitis media,and tinnitus.Despite antibiotic therapy and ventral tube insertion,symptoms did not improve and hearing difficulty was aggravated.Ulcerative,necrotizing granulomatous inflammations with multinucleated giant cells were seen on nasal biopsy.She had recurrent microscopic hematuria and the renal biopsy findings by light and immunofluorescent microscopy did not reveal any abnormalities but diffuse thinning of the glomerular basement membrane (226nm)was observed by electronmicroscopy. With the above clinical findings and biopsy results,we diagnosed Wegener's granulmatosis with thin glomerular basement membrane disease.Thin glomerular basement membrane disease,also called benign recurrent hematuria,is characterized by diffuse thinning of the glomerular basement membrane and hematuria. Weekly low-dose methotrexate together with prednisone was used as treatment regimen because nonglomerular microscopic hematuria may be the first sign of cyclophosphamide-induced renal toxicity.With the above combination therapy, she felt well-being sense and her hearing difficulty was also much improved. She has been treated as an outpatient with glucocorticoid.
Biopsy
;
Giant Cells
;
Glomerular Basement Membrane*
;
Glomerulonephritis
;
Hearing
;
Hematuria
;
Humans
;
Inflammation
;
Kidney
;
Methotrexate
;
Microscopy
;
Otitis
;
Outpatients
;
Prednisone
;
Respiratory System
;
Vasculitis
;
Wegener Granulomatosis*
7.The Clinical Effect of Supplementary Argon Plasma Coagulation after Endoscopic Mucosal Piecemeal Resection of a Gastric Adenoma and Carcinoma.
Sang Joon PARK ; Kee Myung LEE ; Deok Ki KIM ; Sung Jae SIN ; Jae Ho JUNG ; Sung Hyeon JUNG ; Byeong Moo YOO ; Ki Baik HAHM ; Jin Hong KIM
Korean Journal of Gastrointestinal Endoscopy 2007;34(6):291-297
BACKGROUND/AIMS: This study was designed to determine the effect of supplementary argon plasma coagulation (APC) after piecemeal resection of a gastric adenoma or an intramucosal adenocarcinoma. METHODS: Cases of 62 lesions of 56 consecutive patients with either a gastric adenoma or carcinoma were retrospectively reviewed at the Ajou University Medical Center. APC was performed after an endoscopic complete resection using the piecemeal method of endoscopic mucosal resection (EMR) for patients in the EMR-APC group. For patients in the EMR group, APC was not performed. RESULTS: There was no significant difference in the recurrence rate of the cancers for both groups (9.7%, for the EMR group, 6.5% for the EMR-APC group). The recurrence rate of a low grade dysplasia was 6.7% (EMR group) and 6.3% (EMR-APC group) (p=1.000), the recurrence rate for a high grade dysplasia was 11.1% (EMR group) and 25.0% (EMR-APC group) (p=1.000), and the recurrence rate for an intramucosal adenocarcinoma was 14.3% (EMR group) and 0% (EMR-APC group) (p=0.389). The recurrence rates of lesions in which the lesion size was less than 20 mm and over 20 mm for each group were 6.7% and 9.1% (EMR group) (p=1.000) versus 12.5% and 0% (EMR-APC group) (p=0.520). There was also no significant statistical difference in the recurrence rates for both groups according to the location and macroscopic type of lesion. CONCLUSIONS: Supplementary treatment with APC could not significantly reduce the recurrence rate after complete piecemeal resection determined macroscopically. A large- scale and prospective study is necessary to elucidate the clinical significance of supplementary APC for gastric neoplasm treatment.
Academic Medical Centers
;
Adenocarcinoma
;
Adenoma*
;
Argon Plasma Coagulation*
;
Argon*
;
Humans
;
Recurrence
;
Retrospective Studies
;
Stomach Neoplasms
8.Comparative Analysis of Laparoscopic Versus Open Appendectomy for Perforated Appendicitis in Children Under 12 Years Old at a Single Institute.
Jun Ho CHO ; Jin Soo PARK ; Il Dong KIM ; Ki Ho KIM ; Byung Sun SUH ; Sang Wook KIM ; Hye In LIM ; Kook Hyeon JUNG ; Byeong Geon JUNG
Journal of Minimally Invasive Surgery 2013;16(3):69-73
PURPOSE: The purpose of this study is to evaluate the outcome of laparoscopic (LA) vs. open appendectomy (OA) in children under 12 years old with perforated appendicitis. METHODS: We reviewed the medical files of 156 children who underwent LA (n=96), OA (n=59), and conversion (CO) (n=1), and compared duration of operation, length of hospital stay, incidence of wound infection, mechanical ileus, intra-abdominal abscess (IAA), and re-admission. RESULTS: Compared to OA, LA resulted in longer duration of operation (58.32+/-17.105 min vs. 44.27+/-18.735 min; p=0.001), but fewer wound infections (2.1% vs. 10.2%; p=0.054), and fewer cases of mechanical ileus (0% vs. 5.1%; p=0.053). No differences in the length of hospital stay (5.85+/-1.824 days vs. 6.10+/-3.027 days; p=0.526), IAA (2.1% vs. 1.7%; p=1.000), or re-admissions (2.1% vs. 5.1%; p=0.369) were observed. CONCLUSION: We report that although LA showed an association with longer duration of operation compared to OA, it is superior to OA with regard to incidence of wound infection and mechanical ileus.
Abdominal Abscess
;
Appendectomy
;
Appendicitis
;
Child
;
Humans
;
Ileus
;
Incidence
;
Length of Stay
;
Wound Infection
9.Changes of Epidermal Growth Factor in Sera among the Patients with Chronic Hepatitis, Cirrhosis and Hepatocellular Carcinoma.
Yong Hyeon JO ; Byeong Hoon KIM ; Hong Ju KIM ; Yeong Jung CHO ; Je LEE ; Jung Hae CHOI ; Seong Kyu YANG ; Yong Koel YOO ; Kee Woon KWEON ; Dong Hoo LEE
The Korean Journal of Hepatology 1997;3(1):29-39
BACKGROUND/AIMS: Epidermal growth factors (EGF) is known to activate mitogen activated protein kinase (MAP kinase) in hepatocytes by the route of both Raf-dependent and Raf-indefendent pathways. And this is likely to play important role in normal liver cell growth and regeneration. EGF is also reported as a potent mitogen and one of the angiogenic factors. To elucidate the dynamic changes of the serum concentration of epidermal growth factor in chronic liver disease and its correlation with role of EGF and mechanism of tumor development, this study is intended to employ an ELISA in 38 biopsy-proven cases. METHODS: Sera taken out of 5 patients with chronic persistent hepatitis. 4 patients with chronic active hepatitis, 19 patients with liver cirrhosis, 10 patients with hepato-cellular carcinoma that pathological diagnosis was proven later were tested for EGF employing Quantikine ELISA Kits (R & D Systems Inc. Minneapolis, MN). The statistical analysis was evaluated by student's t-test. RESULTS: EGF concentration was 253.33+ 69.5pg/ml(Mean+ SE) in hepatocellular carcinoma, 246.60+ 91.19pg/ml(Mean+ SE) in chronic active hepatitis, 222.71+ 115.97pg/ml (Mean+ SE) in chronic persistent hepatitis, 141.15+ 23.12pg/ml(Mean+ SE) in liver cirrhosis in orders. Serum EGF concentration in hepatocellular carcinoma was significantly higher than that in liver cirrhosis(p value=0.021695). However, comparing to the remaining other groups, no significant difference was found. CONCLUSION: These results support that the reconstruction of the capillary networks in liver cirrhosis resplts in down-regulation of the EGF in comparison to chronic hepatitis. But it is suggested that revaluation of EGF stimulates MAP kinase activity eventually playing in tumorigenesis of the liver with neoangiogenesis.
Angiogenesis Inducing Agents
;
Capillaries
;
Carcinogenesis
;
Carcinoma, Hepatocellular*
;
Diagnosis
;
Down-Regulation
;
Enzyme-Linked Immunosorbent Assay
;
Epidermal Growth Factor*
;
Fibrosis*
;
Hepatitis, Chronic*
;
Hepatocytes
;
Humans
;
Liver
;
Liver Cirrhosis
;
Liver Diseases
;
Liver Regeneration
;
Phosphotransferases
;
Protein Kinases
;
Regeneration
10.Development of Quantification Method for Bioluminescence Imaging.
Hyeon Sik KIM ; Eun Seo CHOI ; Yoon O TAK ; Heung Kook CHOI ; Ju Young LEE ; Jung Joon MIN ; Byeong il LEE
Nuclear Medicine and Molecular Imaging 2009;43(5):451-458
PURPOSE: Optical molecular luminescence imaging is widely used for detection and imaging of bio-photons emitted by luminescent luciferase activation. The measured photons in this method provide the degree of molecular alteration or cell numbers with the advantage of high signal-to-noise ratio. To extract useful information from the measured results, the analysis based on a proper quantification method is necessary. In this research, we propose a quantification method presenting linear response of measured light signal to measurement time. MATERIALS AND METHODS: We detected the luminescence signal by using lab-made optical imaging equipment of animal light imaging system (ALIS) and different two kinds of light sources. One is three bacterial light-emitting sources containing different number of bacteria. The other is three different non-bacterial light sources emitting very weak light. By using the concept of the candela and the flux, we could derive simplified linear quantification formula. After experimentally measuring light intensity, the data was processed with the proposed quantification function. RESULTS: We could obtain linear response of photon counts to measurement time by applying the pre-determined quantification function. The ratio of the re-calculated photon counts and measurement time present a constant value although different light source was applied. CONCLUSION: The quantification function for linear response could be applicable to the standard quantification process. The proposed method could be used for the exact quantitative analysis in various light imaging equipments with presenting linear response behavior of constant light emitting sources to measurement time.
Animals
;
Bacteria
;
Cell Count
;
Enzyme Multiplied Immunoassay Technique
;
Imidazoles
;
Light
;
Luciferases
;
Luminescence
;
Nitro Compounds
;
Optical Imaging
;
Photons
;
Signal-To-Noise Ratio