1.ANALYSIS OF THE FIT IN THE IMPLANT PROSTHESIS USING LASER DISPLACEMENT METER AND THREE-DIMENSIONAL FINITE ELEMENT METHOD.
Ho Beom KWON ; Yung Soo KIM ; Chang Whe KIM
The Journal of Korean Academy of Prosthodontics 2001;39(6):611-624
A precise fit of the implant prosthesis is one of the most important factors in preventing mechanical complications. To analyze the degree of the misfit of implant prosthesis, a modal testing experiment was accomplished. And to interpret the modal testing analysis mathematically, three-dimensional finite element models were established. In the experimental modal testing analysis, with a laser displacement meter, FFT analyzer, impact hammer, etc., natural frequencies of the models with various degree of prosthesis fit were determined after the frequency response function were calculated. In the finite element analysis, the natural frequencies and mode shapes of the models which simulated those of experimental modal testing were computed. The results were as follows : 1. Natural frequencies of the prosthesis-abutment were related to the contact state between components. 2. In the modal testing experiment, the natural frequencies increased from 50micrometer to 200micrometer gap and reached a plateau. 3. In the finite element analysis, the natural frequencies decreased gradually according to the increase of the gap size. 4. In the finite element analysis, the mode shapes of model 1 with misfitting prosthesis showed different patterns from those without misfitting prosthesis. 5. The devices including a laser displacement meter used in this study were useful for measuring the natural frequencies of an implant prosthesis which had various degrees of fit.
Finite Element Analysis
;
Prostheses and Implants*
2.Morphological studies on recombinant virus(recB-8) selected by coinfection of the baculoviruses bombyx mori and autographa californica nuclear palyhedrosis viruses.
Ji Hyun] PARK ; Soo Dong WOO ; Beom Seok PKR ; Kang Sun PYU ; Jai Myung YANG ; In Shik CHUNG ; Seok Kwon KANG
Journal of the Korean Society of Virology 1993;23(1):95-104
No abstract available.
Baculoviridae*
;
Bombyx*
;
Coinfection*
3.Comparative Study between Standard and Totally Tubeless Percutaneous Nephrolithotomy.
Sung Il YUN ; Yoon Hyung LEE ; Jae Soo KIM ; Sung Ryong CHO ; Bum Soo KIM ; Joon Beom KWON
Korean Journal of Urology 2012;53(11):785-789
PURPOSE: Several recent studies have reported the benefits of tubeless percutaneous nephrolithotomy (PNL). Postoperatively, tubeless PNL patients have an indwelling ureteral stent placed, which is often associated with stent-related morbidity. We have performed totally tubeless (tubeless and stentless) PNL in which no nephrostomy tube or ureteral stent is placed postoperatively. We evaluated the safety, effectiveness, and feasibility of totally tubeless PNL. MATERIALS AND METHODS: From March 2008 to February 2012, 57 selected patients underwent standard or totally tubeless PNL. Neither a nephrostomy tube nor a ureteral stent was placed in the totally tubeless PNL group. We compared patient and stone characteristics, operation time, length of hospitalization, analgesia requirements, stone-free rate, blood loss, change in creatinine, and perioperative complications between the standard and totally tubeless PNL groups. RESULTS: There were no significant differences in preoperative patient characteristics, postoperative complications, or the stone-free rate between the two groups, but the totally tubeless PNL group showed a shorter hospitalization and a lesser analgesic requirement compared with the standard PNL group. Blood loss and change in creatinine were not significantly different between the two groups. CONCLUSIONS: Totally tubeless PNL appears to be a safe and effective alternative for the management of renal stone patients and is associated with a decrease in length of hospital stay.
Analgesia
;
Creatinine
;
Hospitalization
;
Humans
;
Kidney Calculi
;
Length of Stay
;
Nephrostomy, Percutaneous
;
Postoperative Complications
;
Stents
;
Ureter
4.Comparative Study between Standard and Totally Tubeless Percutaneous Nephrolithotomy.
Sung Il YUN ; Yoon Hyung LEE ; Jae Soo KIM ; Sung Ryong CHO ; Bum Soo KIM ; Joon Beom KWON
Korean Journal of Urology 2012;53(11):785-789
PURPOSE: Several recent studies have reported the benefits of tubeless percutaneous nephrolithotomy (PNL). Postoperatively, tubeless PNL patients have an indwelling ureteral stent placed, which is often associated with stent-related morbidity. We have performed totally tubeless (tubeless and stentless) PNL in which no nephrostomy tube or ureteral stent is placed postoperatively. We evaluated the safety, effectiveness, and feasibility of totally tubeless PNL. MATERIALS AND METHODS: From March 2008 to February 2012, 57 selected patients underwent standard or totally tubeless PNL. Neither a nephrostomy tube nor a ureteral stent was placed in the totally tubeless PNL group. We compared patient and stone characteristics, operation time, length of hospitalization, analgesia requirements, stone-free rate, blood loss, change in creatinine, and perioperative complications between the standard and totally tubeless PNL groups. RESULTS: There were no significant differences in preoperative patient characteristics, postoperative complications, or the stone-free rate between the two groups, but the totally tubeless PNL group showed a shorter hospitalization and a lesser analgesic requirement compared with the standard PNL group. Blood loss and change in creatinine were not significantly different between the two groups. CONCLUSIONS: Totally tubeless PNL appears to be a safe and effective alternative for the management of renal stone patients and is associated with a decrease in length of hospital stay.
Analgesia
;
Creatinine
;
Hospitalization
;
Humans
;
Kidney Calculi
;
Length of Stay
;
Nephrostomy, Percutaneous
;
Postoperative Complications
;
Stents
;
Ureter
5.An Analytical Comparison of Short-term Effectiveness and Safety Between Thulium:YAG Laser Vaporesection of the Prostate and Bipolar Transurethral Resection of the Prostate in Patients With Benign Prostatic Hyperplasia.
Joon Woo KIM ; Yeon Joo KIM ; Yoon Hyung LEE ; Joon Beom KWON ; Sung Ryong CHO ; Jae Soo KIM
Korean Journal of Urology 2014;55(1):41-46
PURPOSE: In recent years, laser surgery has been widely used to treat benign prostatic hyperplasia (BPH). A thulium:yttrium-aluminium-garnet (Tm:YAG) laser was recently introduced for BPH surgery. We compared the effectiveness and safety of Tm:YAG laser vaporesection of the prostate (ThuVaRP) with that of bipolar transurethral resection of the prostate (TURP). MATERIALS AND METHODS: From January 2010 to December 2012, 86 patients underwent surgical treatment for symptomatic BPH by a single surgeon. We retrospectively analyzed and compared the medical records of 43 patients who underwent ThuVaRP and 43 patients who underwent bipolar TURP. All patients were assessed by using the International Prostate Symptom Score, transrectal ultrasonography, the serum prostate-specific antigen (PSA) level, uroflowmetry, and postvoid residual volume before and 1 month after surgery. All complications were compared between the two groups. RESULTS: ThuVaRP was superior to TURP in catheterization time (p<0.001) and length of hospital stay (p<0.001). However, operation time was longer with ThuVaRP than with TURP (p<0.001). In patients with a large prostate (>50 g), operation time was much longer with ThuVaRP. One month after surgery, the decrease in PSA was greater (p=0.045) with ThuVaRP than with TURP, and the increase in maximal urine flow rate was greater (p<0.001) with ThuVaRP than with TURP. The postoperative complication transient urinary incontinence was significantly different between the ThuVaRP group (nine cases, 20.9%) and the TURP group (two cases, 4.7%). Other complications were comparable between groups. CONCLUSIONS: The effectiveness and safety of ThuVaRP and TURP were comparable. ThuVaRP is a promising alternative surgical technique to TURP for BPH.
Catheterization
;
Catheters
;
Humans
;
Laser Therapy
;
Length of Stay
;
Medical Records
;
Postoperative Complications
;
Prostate*
;
Prostate-Specific Antigen
;
Prostatic Hyperplasia*
;
Residual Volume
;
Retrospective Studies
;
Thulium
;
Transurethral Resection of Prostate
;
Ultrasonography
;
Urinary Incontinence
6.Analysis of a Functional Serotonin Transporter Gene Polymorphism of Normal Controls and Patients with Schizophrenia in Korean Population.
Jung Jin KIM ; Oh Joo KWON ; Soo Jung LEE ; Seok Beom KIM ; Chang Uk LEE ; Chul LEE ; In Ho PAIK
Journal of Korean Neuropsychiatric Association 2002;41(2):223-231
OBJECTIVE: Serotonin is a neurotransmitter which might play an important role in the pathophysiology of schizophrenia. As atypical antipsychotics, which antagonize serotonin receptors, exert effects on negative symptoms of schizophrenia, perturbation of serotonin system has been thought as a good indicator to probe the pathogenesis of schizophrenia. Serotonin transporter is crucial for regulating serotonergic neurotransmission and has a deletion/insertion polymorphism of the gene's transcriptional initiation site. This study was designed to examine the association of schizophrenia and polymorphism of serotonin transporter gene (5-HTTLPR). METHODS: Genomic DNA analysis with polymerase chain reaction (PCR) was used for genetic typing of polymorphism of 5-HTTLPR. It was carried out among a total of 111 patients with schizophrenia and 208 normal controls. The significances of genetic association of the polymorphisms with the disease and with clinical variables were estimated by chi-square test and analysis of variances. RESULTS: The results were as follows: 1) There were no significant differences in allelic or genotype frequencies between the group of patients with schizophrenia and controls. 2) There were no significant differences in positive syndrome scale score of positive and negative syndrome scale (PANSS), duration of illness and number of admission according to 5-HTTLPR genotypes. 3) There was a difference in age at onset according to 5-HTTLPR genotypes. 4) There was a significant difference in negative syndrome scale score and general psychopathology score of PANSS according to 5-HTTLPR genotypes. CONCLUSION: These results suggest that polymorphism of serotonin transporter gene might be related to the pathophysiology of schizophrenia.
Antipsychotic Agents
;
DNA
;
Genotype
;
Humans
;
Neurotransmitter Agents
;
Polymerase Chain Reaction
;
Psychopathology
;
Receptors, Serotonin
;
Schizophrenia*
;
Serotonin Plasma Membrane Transport Proteins*
;
Serotonin*
;
Synaptic Transmission
7.Open Reduction Through the Modified Volar Approach in Complex Dorsal Dislocations of the Metacarpophalangeal Joint.
Soo Joong CHOI ; Bong Cheol KWON ; Yong Beom LEE ; Won Hyoung SHIN
Journal of the Korean Society for Surgery of the Hand 2011;16(3):149-153
PURPOSE: To describe the surgical treatment of the complex dorsal metacarpophalangeal dislocations and its results, emphasizing on the modified volar approach with A1 pulley release. MATERIALS AND METHODS: We experienced 6 cases of dorsal dislocation of the metacarpophalangeal joint. We performed open reduction with the modified volar approach described by Eaton and Dray. Postoperatively posteroanterior and lateral radiographs of the index finger metacarpophalangeal joint and metacarpophalangeal joint range of motion was followed. RESULTS: One case with a large osteochondral fracture was operated with volar and doral approach both. Overall end results were good without any significant restriction of motion and stability of the fingers. CONCLUSION: Modified volar approach with A1 pulley release is an excellent method for complex dorsal metacarpophalangeal dislocations without osteochondral fracture.
Benzodiazepines
;
Dislocations
;
Fingers
;
Metacarpophalangeal Joint
;
Range of Motion, Articular
8.Pilot Study on Resting-State Functional Connectivity under the Effects of Familial Loading in People at Ultra-High Risk for Psychosis.
Beom Jun MIN ; Tae Young LEE ; Sung Nyun KIM ; Hyun Jung HAN ; Da Jung SHIN ; Seo Hyun JO ; Jun Soo KWON
Korean Journal of Schizophrenia Research 2012;15(2):90-98
OBJECTIVES: People at ultra-high risk for psychosis have heterogenous character and different long-term outcomes. We divided ultra-high risk subjects into two subgroups by presence of familial history and tried to find different pattern of functional connectivity of the default mode network (DMN) between the two groups in order to examine the effects familial loading. METHODS: Eleven subjects at clinical-high risk (CHR) group with familial history of psychiatric illness and nineteen subjects of CHR group without familial history were recruited. All the subjects were scanned using resting-state functional magnetic resonance imaging. A posterior cingulate cortex was the seed region of the analysis, and the DMN of the both high risk group were analyzed with voxel-wise two sample T test. RESULTS: The CHR group with familial history showed greater functional connectivity in the precuneus area in contrast with the other high risk subjects (peak-level t=5.49, p<0.001). There were no significant differences in total score on the Positive and Negative Syndrome Scale and Scales of Psychosis-risk Syndrome between the two groups. CONCLUSION: The study suggests that the abnormalities of functional connectivity between precuneus and posterior cingulate area may be associated with the genetic vulnerability of high risk trait.
Gyrus Cinguli
;
Magnetic Resonance Imaging
;
Pilot Projects
;
Psychotic Disorders
;
Seeds
;
Weights and Measures
9.Ultrasonographic and Mammographic Findings of Gynecomastia.
Soo Kyung LEE ; Gyo Chang CHOI ; Hyun Sook HONG ; Young Beom KIM ; Hae Kyung LEE ; Kui Hyang KWON
Journal of the Korean Radiological Society 1996;35(5):825-829
PURPOSE: The purpose of this study is to evaluate the radiologic features and clinical utility of ultrasonography and mammography in cases of gynecomastia. MATERIALS AND METHODS: This study involved 40 men inwhom gynecomastia had been pathologically diagnosed by surgical incision. In 21 cases, a retrospective analysis of ultrasonographic and mammographic findings was performed. RESULTS: Causative factors of gynecomastia among the 40 pathologically-proven cases were idiopathic or pubertal in 33 cases, related to male hormone deficiency in three cases and to chronic liver disease in four. Bilateral involvement was seen in 14 cases, and unilateral involvementin 26 ; among unilateral cases, right side was involved in 10 cases, and the left side in 16. Mammographically, asubareolar discoid lesion was present in 12 cases, diffuse increased breast density was seen in five cases and dendritic marginated subareolar lesion without microcalcification in one. Ultrasonographically, a round smooth marginated low echogenic lesion in the subareolar region was seen in five cases, a diffuse hyperechogenic pattern without definite mass in two cases and an ill defined low echogenic lesion in one. CONCLUSION: The male breast is small, so in cases of gynecomastia, ultrasonography is an effective diagnostic modality. Mamography will, however, be helpful in the detection of microcalcification in cases of gynecomastia seen on sonography.
Breast
;
Gynecomastia*
;
Humans
;
Liver Diseases
;
Male
;
Mammography
;
Retrospective Studies
;
Ultrasonography
10.Correction of Post Burn Extension Contracture of 4, 5th Toes Using Free Flap.
Soo Joong CHOI ; Jae Kyun JUNG ; Bong Cheol KWON ; Yong Beom LEE
Archives of Reconstructive Microsurgery 2013;22(2):90-93
Old post burn contractures on feet still remain challenging problem for reconstructive surgeon. A 43-year-old male visited Hallym University Sacred Heart Hospital with the complain of foot deformity and difficulties in shoe fitting. His right 4th and 5th toes were inverted at dorsal foot. We released the contracture of 4, 5th metatarsophalangeal joint and lengthened extensor tendon by Z-plasty, and covered the resultant defect with the anterolateral thigh flap. The flap was successful and the deformity was corrected. As there have been few reports on reconstruction of foot dorsum, especially on post burn extension contractures in the toes, we report a rare case of contracture release and coverage by free flap.
Adult
;
Burns*
;
Congenital Abnormalities
;
Contracture*
;
Foot
;
Foot Deformities
;
Free Tissue Flaps*
;
Heart
;
Humans
;
Male
;
Metatarsophalangeal Joint
;
Shoes
;
Tendons
;
Thigh
;
Toes*