1.Antimicrobial activity of eight root canal sealers before and after setting.
Denny Y FANG ; Woocheol LEE ; Chern H LAI
Journal of Korean Academy of Conservative Dentistry 2002;27(2):207-211
No abstract available.
Dental Pulp Cavity
2.Effect of genistein on the sexual maturation in immature female rats.
Woocheol LEE ; Sung Ho LEE ; Ryun Sup AHN ; Mi Jung PARK
Korean Journal of Pediatrics 2009;52(1):111-118
PURPOSE: Exposure to dietary phytoestrogens such as genistein during early childhood is a growing public health concern. We examined the effect of early exposure to genistein on sexual maturation in immature rats. METHODS: Weaning (3wk-old) Sprague-Dawley female rats were assigned to three groups (n=6 for each): fed by high dose of genistein (100 mg/kg/d), low dose of genistein (10 mg/kg/d) and control group. First vaginal opening (VO) day was observed. Structural alterations in the ovary and uterus were assessed by histologically. Expression of genes of ERalpha, ERbeta, and progesterone receptor (PR) in the ovary and uterus were investigated by RT-PCR. RESULTS: High genistein group had earlier VO than control and low genistein group. Graafian follicle s and corpora lutea were observed from the ovary of genistein-treated groups, while primary, secondary follicles and small atretic follicles were observed in the control group. Hypertrophy of luminal and glandular uterine epithelia were found in the genistein-treated groups while poor development of gland and fewer myometrial cell layers were evident in control group. In ovary, the transcriptional activities of ERalpha and ERbeta were higher in high genistein group than in controls. In uterus, the transcriptional activities of ERalpha, ERbeta and PR were higher in low genistein group than in controls. CONCLUSION: Acute exposure to genistein during the prepubertal period could activate the reproductive endocrine system resulting in the early onset of puberty in female rats. Further clinical investigation on the effect of genistein on the sexual maturation in children is warranted.
Animals
;
Child
;
Corpus Luteum
;
Endocrine System
;
Estrogen Receptor alpha
;
Estrogen Receptor beta
;
Female
;
Genistein
;
Humans
;
Hypertrophy
;
Ovarian Follicle
;
Ovary
;
Phenobarbital
;
Phytoestrogens
;
Puberty
;
Public Health
;
Rats
;
Receptors, Progesterone
;
Sexual Maturation
;
Uterus
;
Weaning
3.The effect of several root-end filling materials on MG63 osteoblast-like cells.
Jeong Ho LEE ; Won Jun SHON ; WooCheol LEE ; Seung Ho BAEK
Journal of Korean Academy of Conservative Dentistry 2010;35(3):222-228
The purpose of this study was to compare mineral trioxide aggregate (MTA; Dentsply, Tulsa Dental, Tulsa, OK, USA), which is widely used as root-end filling material, with DiaRoot BioAggregate (DB; Innovative BioCaramix Inc, Vancouver, BC, Canada), newly developed product, by using MG63 osteoblast-like cells. MTA, DB, and Intermediate Restorative Material (IRM; Dentsply Caulk, Milford, DE, USA) were used for root-end filling material while tissue culture plastic was used for control group. Each material was mixed and, the mixtures were left to set for 24 hours. MG63 cells were seeded to each group and then they were cultured for attachment for 4 hours. Following the attachment of cells to the root-end filling material, early cellular response was observed. After another 12 hours'culture, the level of attachment between cells and material was observed and in order to identify the effect of each material to bone formation, transforming growth factor beta1 (TGFbeta1) and osteocalin (OC) were estimated by using enzyme-linked immunosorbent assay (ELISA), and the amount of alkaline phosphatase (ALP) was also measured. The data were analyzed using one-way ANOVA. As a result, only at OC and the number of cells which were attached to materials, there was no statistical difference between MTA and DB. At other items, there was statistically significant difference in all groups. Although DB has not shown exactly the same cellular response like that of MTA, the number of attached cells shows that biocompatibility of the material and OC indicates bone formation rate. Therefore, if DB is used for root end filling material, it is expected to lead to similar results to MTA.
Alkaline Phosphatase
;
Aluminum Compounds
;
Calcium Compounds
;
Calcium Hydroxide
;
Drug Combinations
;
Enzyme-Linked Immunosorbent Assay
;
Glutamates
;
Guanine
;
Hydroxyapatites
;
Osteogenesis
;
Oxides
;
Plastics
;
Polymethyl Methacrylate
;
Seeds
;
Silicates
;
Transforming Growth Factor beta1
;
Pemetrexed
4.The Effectiveness of Embolotherapy for Treatment of Hemoptysis in Patients with Varying Severity of Tuberculosis by Assessment of Chest Radiography.
Woocheol KWON ; Young Ju KIM ; Young Han LEE ; Won Yeon LEE ; Myung Soon KIM
Yonsei Medical Journal 2006;47(3):377-383
The effectiveness of percutaneous embolotherapy in cases of hemoptysis due to pulmonary tuberculosis from increasing severity of lung parenchymal injury was compared. The pattern of pleural involvement, as seen on chest radiography and angiography, were comparatively analyzed in 230 patients who were available for follow-ups from March 1992 to December 2003. Chest radiography findings were classified into 4 types based on levels of complicated lesions and pleural involvement. Angiography findings were divided into 4 groups based on the level of blood supply to lesions. Early hemostasis with respect to radiographic group were as follows: Type I-92% (73/79), Type II-80% (52/65), Type III-70% (42/60), and Type IV-56% (52/92); there was an average success rate of 73% (219/296), and continued hemostasis was found in 80% of Type I patients (62/77), 77% of Type II patients (41/53), 62% of Type III patients (25/40), and 45% of Type IV patients (27/60), with an average long-term hemostatic rate of 67% (155/230). Increasing severity of pleural involvement and associated complications correlated with increasing development of systemic collateral arteries other than the bronchial artery. The severely increased circulation in systemic collateral arteries makes it difficult to predict good hemostatic results following embolization. Therefore, we recommend aggressive treatment, such as surgical intervention, after embolization in such instances.
Tuberculosis, Pulmonary/*complications/radiography
;
Treatment Outcome
;
Severity of Illness Index
;
Middle Aged
;
Male
;
Humans
;
Hemoptysis/*microbiology/radiography/*therapy
;
Follow-Up Studies
;
Female
;
*Embolization, Therapeutic
;
Angiography
;
Aged, 80 and over
;
Aged
;
Adult
;
Adolescent
5.The Effectiveness of Embolotherapy for Treatment of Hemoptysis in Patients with Varying Severity of Tuberculosis by Assessment of Chest Radiography.
Woocheol KWON ; Young Ju KIM ; Young Han LEE ; Won Yeon LEE ; Myung Soon KIM
Yonsei Medical Journal 2006;47(3):377-383
The effectiveness of percutaneous embolotherapy in cases of hemoptysis due to pulmonary tuberculosis from increasing severity of lung parenchymal injury was compared. The pattern of pleural involvement, as seen on chest radiography and angiography, were comparatively analyzed in 230 patients who were available for follow-ups from March 1992 to December 2003. Chest radiography findings were classified into 4 types based on levels of complicated lesions and pleural involvement. Angiography findings were divided into 4 groups based on the level of blood supply to lesions. Early hemostasis with respect to radiographic group were as follows: Type I-92% (73/79), Type II-80% (52/65), Type III-70% (42/60), and Type IV-56% (52/92); there was an average success rate of 73% (219/296), and continued hemostasis was found in 80% of Type I patients (62/77), 77% of Type II patients (41/53), 62% of Type III patients (25/40), and 45% of Type IV patients (27/60), with an average long-term hemostatic rate of 67% (155/230). Increasing severity of pleural involvement and associated complications correlated with increasing development of systemic collateral arteries other than the bronchial artery. The severely increased circulation in systemic collateral arteries makes it difficult to predict good hemostatic results following embolization. Therefore, we recommend aggressive treatment, such as surgical intervention, after embolization in such instances.
Tuberculosis, Pulmonary/*complications/radiography
;
Treatment Outcome
;
Severity of Illness Index
;
Middle Aged
;
Male
;
Humans
;
Hemoptysis/*microbiology/radiography/*therapy
;
Follow-Up Studies
;
Female
;
*Embolization, Therapeutic
;
Angiography
;
Aged, 80 and over
;
Aged
;
Adult
;
Adolescent
6.Development of PC-based Software to Analyze Dynamic Cerebral Perfusion CT Quantitatively and to Reformat Perfusion Maps.
Young Han LEE ; Woocheol KWON ; Myeong Sub LEE ; Yong Min HUH ; Myung Soon KIM
Journal of the Korean Radiological Society 2005;53(2):79-84
PURPOSE: The purpose of this study was to develop PC-based perfusion software using Microsoft Windows. This software was developed to reformat perfusion maps including CBV (Cerebral Blood Volume), MTT (Mean Transit Time), and CBF (Cerebral Blood Flow) maps and to analyze perfusion quantitatively. MATERIALS AND METHODS: Windows-based perfusion software was developed using IDL (Interactive Data Language) as the development tool. The perfusion software was written to load the source image from dynamic first-pass cerebral perfusion CT and to reformat perfusion maps. Mean perfusion values in gray matter and white matter were calculated and compared to previously calculated data reported in literature. RESULTS: This software reformatted first pass perfusion maps in a user-friendly PC and calculated CBV, MTT, and CBF values. The values were within the normal range of the mean values when compared to previous studies. CONCLUSION: CT perfusion maps and perfusion values can be obtained by using the newly developed PC-based perfusion software. Further study is needed to achieve more precise values. However, we believe that in the future, this program may be used in various clinical settings.
Perfusion*
;
Reference Values
7.Occlusion of Traumatic Carotid Cavernous Fistula by Incidentally Formed Thrombus During the Interventional Procedure: A Case Report.
Kum WHANG ; Myeong Sub LEE ; Myung Soon KIM ; Ji Yong LEE ; Woocheol KWON
Korean Journal of Radiology 2006;7(3):215-217
In this report, we present a rare case of traumatic carotid cavernous fistula that was occluded during the interventional procedure by incidentally formed blood clot. Sudden occlusion of the fistula and the resolution process of the precarious blood clot can be clearly seen on the serial angiogram.
Vascular Surgical Procedures/*adverse effects
;
Treatment Outcome
;
Male
;
Incidental Findings
;
Humans
;
Craniocerebral Trauma/*complications
;
Carotid-Cavernous Sinus Fistula/etiology/*radiography/*surgery
;
Carotid Artery Thrombosis/*etiology/*radiography
;
Adult
8.A survey of experience-based preference of Nickel-Titanium rotary files and incidence of fracture among general dentists.
Woocheol LEE ; Minju SONG ; Euiseong KIM ; Hyojin LEE ; Hyeon Cheol KIM
Restorative Dentistry & Endodontics 2012;37(4):201-206
OBJECTIVES: The purpose was to investigate the preference and usage technique of NiTi rotary instruments and to retrieve data on the frequency of re-use and the estimated incidence of file separation in the clinical practice among general dentists. MATERIALS AND METHODS: A survey was disseminated via e-mail and on-site to 673 general dentists. The correlation between the operator's experience or preferred technique and frequency of re-use or incidence of file fracture was assessed. RESULTS: A total of 348 dentists (51.7%) responded. The most frequently used NiTi instruments was ProFile (39.8%) followed by ProTaper. The most preferred preparation technique was crown-down (44.6%). 54.3% of the respondents re-used NiTi files more than 10 times. There was a significant correlation between experience with NiTi files and the number of reuses (p = 0.0025). 54.6% of the respondents estimated experiencing file separation less than 5 times per year. The frequency of separation was significantly correlated with the instrumentation technique (p = 0.0003). CONCLUSIONS: A large number of general dentists in Korea prefer to re-use NiTi rotary files. As their experience with NiTi files increased, the number of re-uses increased, while the frequency of breakage decreased. Operators who adopt the hybrid technique showed less tendency of separation even with the increased number of re-use.
Chimera
;
Surveys and Questionnaires
;
Dentists
;
Electronic Mail
;
Humans
;
Incidence
;
Korea
9.In vitro evaluation of cleaning efficacy of various irrigation methods in mandibular molars.
So Young LEE ; Won Jun SON ; Woocheol LEE ; Kee Yeon KUM ; Kwang Shik BAE ; Seung Ho BAEK
Journal of Korean Academy of Conservative Dentistry 2009;34(3):215-222
The aim of this in vitro study was to evaluate the cleaning efficacy of various irrigation methods in the mandibular mesial roots. The forty five mesial root canals were shaped by Profile .06 instruments to apical size #30 and irrigated with 5 ml of 3.5% NaOCl. The teeth were divided into 3 groups and irrigated finally for 1 minute; Group 1: syringe irrigation, Group 2: ultrasonic irrigation, Group 3: RinsEndo irrigation. After histological processing, the cross sections of apical 1, 3, and 5 mm level were examined with an optical microscope. The cleanliness values of canals and isthmuses were calculated and analyzed by Mann-Whitney U test. 1. There were no significant differences in both canal and isthmus cleanliness between syringe irrigation and ultrasonic irrigation except 5 mm level of isthmus. 2. RinsEndo irrigation had significantly higher canal cleanliness values than syringe irrigation at 1 mm and 3 mm levels (p < 0.05). Also, RinsEndo irrigation had significantly higher isthmus cleanliness values than syringe irrigation at all levels evaluated (p < 0.05). 3. There were no statistical differences in both canal and isthmus cleanliness between ultrasonic irrigation and RinsEndo irrigation except 3 mm level of canal. From this study, RinsEndo irrigation can be useful as an additional irrigation procedure.
Dental Pulp Cavity
;
Molar
;
Syringes
;
Tooth
;
Ultrasonics
10.The effect of Treponema denticola immunoinhibitory protein on cytokine expression in T cells.
Sang Yup LEE ; Won Jun SHON ; Woocheol LEE ; Seung Ho BAEK ; Kwang Shik BAE ; Sungsam LIM
Journal of Korean Academy of Conservative Dentistry 2004;29(5):479-484
Immunoinhibitory protein extracted from sonicated Treponema denticola have been shown to suppress cell cycle progression of human lymphocytes. To study in detail about the effect of this microorganism on the function of lymphocytes, we investigated the levels of Interleukin-2 (IL-2) and Interleukin-4 (IL-4) production by T lymphocytes before and after the addition of 12.5 microg/ml T. denticola sonicated extracts. In this study, levels of IL-2 and IL-4 produced from T cells pretreated with sonicated extracts were evaluated by using the quantitative sandwich enzyme immunoassay technique. In response to phytohemagglutinin (PHA) stimulation, T cell produced increased levels of IL-2 and IL-4. However, the expressions of both cytokines were significantly inhibited when PHA activated-T cells were pre-exposed to sonicated T. denticola extracts (p < 0.05). These findings suggest that the T. denticola sonicated extracts induced-immunosuppression in Th1 and Th2 cell functions could be a part of the pathogenic mechanism of the endodontic failure associated with this microorganism.
Cell Cycle
;
Cytokines
;
Humans
;
Immunoenzyme Techniques
;
Interleukin-2
;
Interleukin-4
;
Lymphocytes
;
T-Lymphocytes*
;
Th2 Cells
;
Treponema denticola*
;
Treponema*