1.Insertion and removal torques according to orthodontic mini-screw design.
Jung Yul CHA ; Tae Min YOON ; Chung Ju HWANG
Korean Journal of Orthodontics 2008;38(1):5-12
OBJECTIVE: This study was designed to analyze the primary and secondary stability characteristics of orthodontic mini-screws of tapered design when compared with the cylinder mini-screw. METHODS: A total of 48 mini-screws were placed into the buccal alveolar bone of the mandible in 6 male beagle dogs. Comparison was made between tapered and cylinder type mini-screws (Biomaterials Korea, Seoul, Korea). Maximum insertion torque (MIT) was measured using a torque sensor (Mark-10, MGT 50, USA) during installation, and maximum removal torque (MRT) was recorded after 3 and 12 weeks of loading. RESULTS: Taper mini-screws showed a higher MIT value of 22.3 Ncm compared with cylinder mini-screw showing 13.6 Ncm (p < 0.001). The MRT of the taper mini-screw showed a significantly higher value of 9.1 Ncm than those of cylinder mini-screw of 5.7 Ncm at 3-weeks after installation (p < 0.05). However, there was no difference in the MRT value between the taper and cylinder mini-screws at 12 weeks of loading. CONCLUSIONS: These results showed that the high insertion torque of the taper mini-screw design increases initial stability until 3 weeks of loading, but does not have any effect on the secondary stability at 12 weeks of loading.
Animals
;
Dogs
;
Humans
;
Korea
;
Male
;
Mandible
;
Torque
2.Subgenus classification of Acanthamoeba by riboprinting.
Dong Il CHUNG ; Hak Sun YU ; Mee Yul HWANG ; Tae Ho KIM ; Tae Ook KIM ; Ho Cheol YUN ; Hyun Hee KONG
The Korean Journal of Parasitology 1998;36(2):69-80
Subgenus classification of Acanthamoeba remains uncertain. Twenty-three reference strains of Acanthamoeba including 18 (neo)type-strains were subjected for classification at the subgenus level by riboprinting. PCR/RFLP analysis of 18S rRNA gene (rDNA). On the dendrogram reconstructed on the basis of riboprint analyses, two type-strains (A. astronyxis and A. tubiashi) of morphological group 1 diverged early from the other strains and were quite distinct from each other. Four type-strains of morphological group 3, A. culbertsoni, A. palestinensis, A. healyi were considered taxonomically valid, but A. pustulosa was regarded as an invalid synonym of A. palestinensis. Strains of morphological group 2 were classified into 6 subgroups. Among them, A. griffini which has an intron in its 18S rDNA was the most divergent from the remaining strains. Acanthamoeba castellanii Castellani, A. quina Vil3, A. lugdunensis L3a, A. polyphaga Jones, A. triangularis SH621, and A. castellanii Ma strains belonged to a subgroup, A. castellanii complex. However, A. quina and A. lugdunensis were regarded as synonyms of A. castellanii. The Chang strain could be regarded as A. hatchetti. Acanthamoeba mauritaniensis, A. divionensis, A. paradivionensis could be considered as synonyms of A. rhysodes. Neff strain was regarded as A. polyphaga rather than as A. castellanii. It is likely that riboprinting can be applied for rapid identification of Acanthamoeba isolated from the clinical specimens and environments.
Acanthamoeba/genetics
;
Acanthamoeba/classification*
;
Animal
;
DNA, Protozoan/analysis
;
Polymerase Chain Reaction/methods*
;
Polymorphism, Restriction Fragment Length*
;
RNA, Protozoan/genetics
;
RNA, Protozoan/analysis*
;
RNA, Ribosomal, 18S/genetics
;
RNA, Ribosomal, 18S/analysis*
3.A Case of Cutaneous Larva Migrans.
Young Tae KIM ; Mu Hyun SONG ; Seong Yul LEE ; Jong Suk LEE ; Kyu Wang HWANG
Korean Journal of Dermatology 2002;40(2):209-211
A 30-year-old man presented with several intensely prurutic erythematous serpiginous thread-like skin lesions which began as a small papule on the upper back 2 weeks prior to his visit and was migrating to the lower back and buttock area. The laboratory examination showed non-specific findings. Histopathologic examination revealed a pustular burrow containing numerous eosinophils in the epidermis. In the dermis, there was a diffuse and occasionally dense perivascular inflammatory cell inflammation consisting of eosinophils and some lymphocytes. The patient was treated with oral albendazole, antihistamine and topical corticosteroid for 2 weeks without recurrence for 6 months up to now. Multiple histologic sections were made without success in demonstrating parasitic tissue in the epidermis, however, the clinical and histopathologic features were consistent with cutaneous larva migrans.
Adult
;
Albendazole
;
Buttocks
;
Dermis
;
Eosinophils
;
Epidermis
;
Humans
;
Inflammation
;
Larva Migrans*
;
Lymphocytes
;
Recurrence
;
Skin
4.Bacterial endosymbiosis within the cytoplasm of Acanthamoeba lugdunensis isolated from a contact lens storage case.
Dong Il CHUNG ; Hyun Hee KONG ; Tae Ho KIM ; Mee Yul HWANG ; Hak Sun YU ; Ho Cheol YUN ; Sung Yong SEOL
The Korean Journal of Parasitology 1997;35(2):127-133
Transmission electron microscopy of an Acanthamoeba isolate (KA/L5) from a contact lens case revealed bacterial endosymbionts within cytoplasm of the amoebae. The Acanthamoeba isolate belonged to the morphological group II. Based on the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) of 18S ribosomal RNA coding DNA (rDNA), the isolate was identified as A. lugdunensis. Strain typing by isoenzyme analysis using isoelectric focusing (IEF) and mitochondrial (Mt) DNA RFLP revealed that the isolate was closely related with KA/L1, the most predominant type of isolates from contact lens storage cases, KA/E2, a clinical isolate, KA/W4, previously reported to host endosymbionts, and L3a strains of A. lugdunensis. The endosymbionts were similar to those of KA/W4 in aspects that they were randomly distributed in both trophozoites and cysts, and were rod-shaped bacteria measuring approximately 1.38 x 0.50 microns. But the number of endosymbionts per amoeba was significantly lower than that of KA/W4. They were neither limited by phagosomal membranes nor included in lacunaelike structure.
Acanthamoeba/microbiology*
;
Acanthamoeba/cytology
;
Animal
;
Bacteria/isolation & purification*
;
Colony Count, Microbial
;
Contact Lenses*
;
Cytoplasm/microbiology
;
Symbiosis*
5.Deliberate Self-harm among Young People Begins to Increase at the Very Early Age: a Nationwide Study.
Kwang Yul JUNG ; Taerim KIM ; Sung Yeon HWANG ; Tae Rim LEE ; Hee YOON ; Tae Gun SHIN ; Min Seob SIM ; Won Chul CHA ; Hong Jin JEON
Journal of Korean Medical Science 2018;33(30):e191-
BACKGROUND: Suicide in young people is one of most common cause of death; and deliberate self-harm (DSH) is important indicator of suicide. It is currently unclear how old the rate begins to increase or when it reaches to the same level with adults. The purpose of this study was to find beginning age of DSH and compare their characteristics with adults. METHODS: This study retrospectively reviewed 5 years of nationwide prospective registry named Emergency Department-based Injury In-depth Surveillance (EDIIS) registry composed of all injured patients who were admitted to twenty tertiary university hospital emergency departments. Injured patients aged 29 years or younger from January 1, 2011 to December 31, 2015 were included. Incidence rate of DSH in all age was described. Patients were stratified by age: early teenage (11–15 years), late teenage (16–19 years), and early adulthood (20–29 years). Data of early teenage group were compared to those of other groups for examining their characteristics. RESULTS: Among 588,549 injury patients, 8,400 patients reported DSH. The rate began to rise at age 11 and reach at age 16 which was equivalent to that of age 20 to 29. Early teenage had significantly higher excess mortality ratio based injury severity score (EMR-ISS) and had almost same level without significant difference in operation incidence or mortality compared to late teenage and early adulthood. CONCLUSION: DSH rate began to rise at age 11, reaching adulthood level at age 16 in Korea.
Adult
;
Cause of Death
;
Emergencies
;
Emergency Service, Hospital
;
Humans
;
Incidence
;
Injury Severity Score
;
Korea
;
Mortality
;
Prospective Studies
;
Retrospective Studies
;
Self-Injurious Behavior*
;
Suicide
6.Two Cases of Amnioinfusion for the Midtrimester Oligohydroamnios.
Tae Yul HWANG ; U Chul KIM ; Jeong Hun LEE ; Jeong Rye LEE ; Jee Hyun PARK ; Moon Whan IM ; Byong Ick LEE ; Woo Young LEE
Korean Journal of Obstetrics and Gynecology 2001;44(12):2325-2328
Reduced amniotic fluid volume generally leads to a poor perinatal outcome, especially when it is observed in the second trimester. The recent obstetric literatures have been reporting on various applications of amnioinfusion in the diagnostic, prophylactic and therapeutic management of oligohydroamnios. We experienced two cases of amnioinfusion, which were used to diagnose or to manage the midtrimester oligohydroamnios and we report them with a brief review.
Amniotic Fluid
;
Female
;
Humans
;
Pregnancy
;
Pregnancy Trimester, Second*
7.The Superiority of the Laryngeal Mask Airway to the Pentax(R)AirwayScope Used by an Unskilled Pre-hospital Rescuer: A Randomized, Controlled, Crossover Mannequin Study.
Seong Youn HWANG ; Tae Yong SHIN ; Young Rock HA ; Young Sik KIM ; Han Ho JEONG ; Jung Hyun KIM ; Kyoung Yul LEE ; Young Hwan LEE ; Chong Kun HONG
Journal of the Korean Society of Emergency Medicine 2013;24(4):446-452
INTRODUCTION: Recent studies have highlighted the use of a video laryngoscope, a promising airway device that enables faster intubation than a Macintosh laryngoscope without the cessation of chest compressions. The aim of this study was to compare the performance of a Pentax AirwayScope (AWS) with that of a laryngeal mask airway (LMA) when utilized by unskilled personnel in a mannequin model while performing chest compressions. METHODS: We conducted a randomized controlled crossover trial to compare the effects of these two airway devices. A total of 36 participants performed intubation on a mannequin, with each device in both common and moderate level of difficulty airway scenarios. The time to successful ventilation, rate of ventilation success, and subjective difficulty in manipulating the devices were compared. RESULTS: In a scenario with airways of common difficulty, the LMA had a shorter time interval to successful ventilation than the AWS (13.6 vs. 25.2 seconds, respectively, p<0.001). In a scenario with moderately difficult airways, the LMA was also shorter than the AWS (14.5 vs. 26.9 seconds, respectively, p<0.001). For every level of difficulty for the airway, the LMA showed a higher successful ventilation rate and a lower extent of difficulty in device operation than the AWS (p<0.05). CONCLUSION: In the pre-hospital setting, using the LMA could enable an unskilled rescuer to establish airway patency more rapidly. LMA might also be safer and easier for operation than the AWS.
Intubation
;
Intubation, Intratracheal
;
Laryngeal Masks
;
Laryngoscopes
;
Manikins
;
Thorax
;
Ventilation
8.Shifting in Seroprevalence of HBsAg and Anti-HCV during Recent 10 Years in Adults Resident in Daegu and Gyeongbuk Province.
Kyung In LEE ; Kyung Sik PARK ; Hye Jin SEO ; Tae Yul KIM ; Eun Soo KIM ; Byoung Kuk JANG ; Woo Jin CHUNG ; Kwang Bum CHO ; Jae Seok HWANG
The Korean Journal of Gastroenterology 2011;58(2):82-87
BACKGROUND/AIMS: There have been only few studies on the population-adjusted seroprevalence of HBV and HCV and on the change of them for more than 10 years in Korea. Therefore, this study was performed to evaluate them at a single health center in Daegu and Gyeongbuk province considering the population composition ratio. METHODS: We analyzed the seromarkers of HBV and HCV of 6,237 randomly sampled adults who had received health screening at the health promotion center in Dongsan hospital during the periods from year 1997 to 1999 (Period A) and from 2007 to 2009 (Period B). RESULTS: The seroprevalences of HBsAg, anti-HBs, anti-HBc and anti-HCV were 4.8%, 70.2%, 47.4%, and 0.5%, respectively. There is no difference in the seroprevalence of HBsAg between period A and B. However, downward tendency of prevalence through A to B from 6.8% to 4.5% could be found in 40s, and upward tendency from 4.7% to 6.8% in 50s. As for the seroprevalence of anti-HCV, although there was no difference through A to B, for 50s, it decreasd from 2.0% to 0.3% (p=0.007). However, for 60s, it increased as much as decreasd for 50s. CONCLUSIONS: The seroprevalence of HBsAg in Daegu/Gyeongbuk province was 4.8% and showed no difference through the time period of 10 years. The seroprevalence of anti-HCV was 0.5% and also showed no difference through the time periods.
Adult
;
Aged
;
Female
;
Hepatitis B/*epidemiology
;
Hepatitis B Antibodies/*blood
;
Hepatitis B Surface Antigens/*blood/immunology
;
Hepatitis C/*epidemiology
;
Hepatitis C Antibodies/*blood
;
Humans
;
Male
;
Middle Aged
;
Republic of Korea
;
Rural Population
;
Seroepidemiologic Studies
;
Urban Population
9.New Korean Guidelines for the Diagnosis and Management of Dry Eye Disease
Dong Hyun KIM ; Youngsub EOM ; Chang Ho YOON ; Hyun Soo LEE ; Ho Sik HWANG ; Jin Hyoung KIM ; Tae-im KIM ; Jong Suk SONG ; Kyoung Yul SEO ; Kyung Chul YOON ;
Korean Journal of Ophthalmology 2024;38(2):156-163
New Korean guidelines for the diagnosis and management of dry eye disease were developed based on literature reviews by the Korean Dry Eye Guideline Establishment Committee, a previous dry eye guideline by Korean Corneal Disease Study Group, a survey of Korean Dry Eye Society (KDES) members, and KDES consensus meetings. The new definition of dry eye was also proposed by KDES regular members. The new definition by the regular members of the KDES is as follows: “Dry eye is a disease of the ocular surface characterized by tear film abnormalities and ocular symptoms.” The combination of ocular symptoms and an unstable tear film (tear breakup time <7 seconds) was considered as essential components for the diagnosis of dry eye. Schirmer test and ocular surface staining were considered adjunctive diagnostic criteria. The treatment guidelines consisted of a simplified stepwise approach according to aqueous deficiency dominant, evaporation dominant, and altered tear distribution subtypes. New Korean guidelines can be used as a simple, valid, and accessible tool for the diagnosis and management of dry eye disease in clinical practice.
10.The significance of the TDx-FLM assay in the fetal lung maturity.
Moon Whan IM ; Wonsick CHOE ; Sung Ook HWANG ; Tae Yul HWANG ; Jeong Rye LEE ; Jee Hyun PARK ; In Hwa NOH ; Seung Kwon KOH ; Byoung Ick LEE ; Woo Young LEE ; Yun Chul HONG ; Moon Soo KANG ; Soo Hwan PAI
Korean Journal of Obstetrics and Gynecology 2001;44(11):1968-1972
OBJECTIVE: The TDX analyzer, an automated fluorescence polarimeter, has been utilized to assess surfactant content in amniotic fluid. Amniostat-FLM is an immunologic semiquantitative agglutination test for determining the presence of phosphatidylglycerol in human amniotic fluid at concentration indicative of fetal lung maturity. We evaluated the usefulness of the recently introduced TDx-FLM assay in determining fetal lung maturity. METHODS: Seventy-three samples of amniotic fluid were analyzed. Among them, 18 samples were compared with Amniostat-FLM assay. RESULTS: Surfactant/albumin ratio using TDx-FLM assay increased with longer gestational age. And the concordance rate between Amniostat-FLM assay and TDx-FLM assay was 66.9%. CONCLUSION: The TDx-FLM assay appears to be a useful test in the field of fetal lung maturity testing.
Agglutination Tests
;
Amniotic Fluid
;
Female
;
Fluorescence
;
Gestational Age
;
Humans
;
Lung*