1.Introduction to Distribution and Ecology of Sterile Conks of Inonotus obliquus.
Min Woong LEE ; Hyeon HUR ; Kwang Choon CHANG ; Tae Soo LEE ; Kang Hyeon KA ; L JANKOVSKY
Mycobiology 2008;36(4):199-202
Inonotus obliquus is a fungus that causes white heart rot on several broad-leaved species. This fungus forms typical charcoal-black, sterile conks (chaga) or cinder conks on infected stems of the birche (Betula spp). The dark brown pulp of the sterile conk is formed by a pure mycelial mass of fungus. Chaga are a folk remedy in Russia, reflecting the circumboreal distribution of I. obliquus in boreal forest ecosystems on Betula spp. and in meridional mountain forests on beech (Fagus spp.) in Russia, Scandinavia, Central Europe, and Eastern Europe. Distribution at lower latitudes in Western and Southern Europe, Northern America, Asia, Japan, and Korea is rare. Infected trees grow for many years without several symptoms of decline. The infection can penetrate through stem injuries with exterior sterile conks developing later. In the Czech Republic, cinder conk is found on birches inhabiting peat bogs and in mountain areas with a colder and more humid climate, although it is widespread in other broad leaved species over the Czech Republic. The most common hosts are B. pendula, B. pubescens, B. carpatica, and F. sylvatica. Less frequent hosts include Acer campestre, Acer pseudoplatanus, Alnus glutinosa, Alnus incana, Fraxinus excelsior, Quercus cerris, Q. petraea, Q. robur, Q. delachampii, and Ulmus sp.
Acer
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Alnus
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Asia
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Betula
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Climate
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Czech Republic
;
Ecology
;
Ecosystem
;
Europe
;
Europe, Eastern
;
European Continental Ancestry Group
;
Fagus
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Fraxinus
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Fungi
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Heart
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Humans
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Japan
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Korea
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Medicine, Traditional
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North America
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Quercus
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Russia
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Scandinavia
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Soil
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Trees
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Ulmus
;
Wetlands
2.Two Cases of Familial B-Thalassemia Minor.
Jeomg Hwa HWANG ; Hyeon Jeong LEE ; Jun HUR ; Gae Soon YEON ; Hee Jin KIM ; Tae Jun YUN ; Chan Yung KIM
Journal of the Korean Pediatric Society 1995;38(6):867-871
No abstract available.
3.The etching effects and microtensile bond strength of total etching and self-etching adhesive system on unground enamel.
Sun Kyong OH ; Bock HUR ; Hyeon Cheol KIM
Journal of Korean Academy of Conservative Dentistry 2004;29(3):273-280
The purpose of this study was to evaluate the etching effects and bond strength of total etching and self-etching adhesive system on unground enamel using scanning electron microscopy and microtensile bond strength test. The buccal coronal unground enamel from human extracted molars were prepared using low-speed diamond saw. Scotchbond Multi-Purpose (group SM), Clearfil SE Bond (group SE), or Adper Prompt L-Pop (group LP) were applied to the prepared teeth, and the blocks of resin composite (Filtek Z250) were built up incrementally. Resin tag formation was evaluated by scanning electron microscopy, after removal of enamel surface by acid dissolution and dehydration. For microtensile bond strength test, resin-bonded teeth were sectioned to give a bonded surface area of 1mm2. Microtensile bond strength test was perfomed. The results of this study were as follows. 1. A definite etching pattern was observed in Scotchbond Multi-Purpose group. 2. Self-etching groups were characterized as shallow and irregular etching patterns. 3. The results (mean) of microtensile bond strength were SM; 26.55 MPa, SE; 18.15 MPa, LP; 15.57 MPa. SM had significantly higher microtensile bond strength than SE and PL (p < 0.05), but there was no significant differance between SE and PL.
Adhesives*
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Dehydration
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Dental Enamel*
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Diamond
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Humans
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Microscopy, Electron, Scanning
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Molar
;
Tooth
4.Analysis for the Patterns of Medical Care Utilization during 19 Years (1990-2008) and Its Related Factors in Hypertensive Patients Using National Patient Survey in Korea.
Nam Wook HUR ; Hyeon Chang KIM
Journal of the Korean Society of Hypertension 2014;20(1):8-20
BACKGROUND: To analyze the patterns of medical care utilization and its related factors in hypertensive patients during 19 years (1990-2008), utilizing national patient survey in Korea. METHODS: Using seven surveyed data, age-standardized medical care utilization increasing ratios for the inpatients and outpatients compared to the year of 1990 were calculated, respectively. Changes of medical facilities (%) of patients used in 1990, 1999, and 2008 were compared. For the outpatients, median length of stay and discharge mortality rate per 1,000 persons were calculated. Multivariate logistic regression methods were used to identify related factors of the resident patients and the comparison characteristics between hypertensives and the others of all subjects. Sample weights were used. RESULTS: The medical care utilization of hypertensives were increased for both inpatients and outpatients. However, the ratios were dramatically diminished after the standardization. Age-standardized ratios were 3.6 in outpatients and 5.9 in inpatients compared to 1990. For the outpatients, mainly used medical facilities were changed from general hospital to convalescent hospital. Also, median length of stay and discharge mortality rate were increased up to 5 times and 4 times compared to 1990. The odds of being resident patients were related with discharge as death and using oriental medical center convalescent hospital in 2008. Hypertensive patients were older than the others. Confined to hypertensive patients, member of National Health Insurance was more tend to be outpatients but less inpatients. CONCLUSIONS: Aging population and long-term care Act were presumed as the main reason for the increasing of medical care utilization in 1990 to 2008.
Aging
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Health Care Surveys
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Hospitals, Convalescent
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Hospitals, General
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Humans
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Hypertension
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Inpatients
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Korea
;
Length of Stay
;
Logistic Models
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Long-Term Care
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Mortality
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National Health Programs
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Outpatients
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Utilization Review
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Weights and Measures
5.Relative efficacy of three Ni-Ti file systems used by undergraduates.
Hyeon Cheol KIM ; Jeong Kil PARK ; Bock HUR
Journal of Korean Academy of Conservative Dentistry 2005;30(1):38-48
The purpose of this study was to compare and evaluate the shaping ability of the three different Ni-Ti file systems used by undergraduate students. Fifty undergraduate students prepared 150 simulated curved root canals in resin blocks with three Ni-Ti file systems - ProFile(R) (PF), Manual ProTaper(R) (MPT), Rotary ProTape(R) (RPT). Every student prepared 3 simulated root canals with each system respectively. After root canal preparation, the Ni-Ti files were evaluated for distortion or breakage. Assessments were made according to the presence of various types of canal aberrations. The pre- and post-instrumented canal images were attained and superimposed. The instrumented root canal width were measured and calculated for the net transportation (deviation) and the centering ratio. Under the condition of this study, both ProTaper(R) systems allowed significantly more removal of root canal wall than the ProFile(R) system. In the important other aspects such as the centering ratio, there was no significant differences between the systems. Novice dental students were able to prepare curved root canals with any kinds of Ni-Ti file systems with little aberration and great conservation of tooth structure. Students want to learn effective methods and at the same time simple rotary procedures. The rotary ProTaper(R) systems were one of the most compatible to these students from the point of view of cutting ability. The ProFile(R) system was also compatible in safe and gentle shaping.
Dental Pulp Cavity
;
Humans
;
Root Canal Preparation
;
Students, Dental
;
Tooth
;
Transportation
6.Is the Relationship between Depression and C Reactive Protein Level Moderated by Social Support in Elderly?-Korean Social Life, Health, and Aging Project (KSHAP)
Nam Wook HUR ; Hyeon Chang KIM ; Linda WAITE ; Yoosik YOUM
Psychiatry Investigation 2018;15(1):24-33
OBJECTIVE: To investigate the buffering effects of social support as an effects modifier in the association between depression and inflammation in the elderly. METHODS: We analyzed the Korean Social Life, Health, and Aging Project (KSHAP) for questionnaire, clinical, and laboratory data of 530 older adults living in a rural community. Multivariate regression models were used to investigate the association between depressive symptoms and C-reactive protein level (CRP), a marker of inflammation, at varying levels of social support. RESULTS: Social support affected the association between depressive symptoms and CRP level in both sexes. However, the direction of effects modification was different for men and women. In men, a higher CRP level was significantly associated with depressive symptoms only among those with lower support from a spouse or family members. By contrast, in women, the association was significant only among subgroups with higher spousal or family support. Social support from neighbors or friends did not affect the depression-inflammation relationship in men but modestly affected the relationship in women. CONCLUSION: Our findings suggest that social support may have a buffering effect in the relationship between depression and inflammation in elderly Koreans. But the influence of social support may run in different directions for men and women.
Adult
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Aged
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Aging
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C-Reactive Protein
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Depression
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Female
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Friends
;
Humans
;
Inflammation
;
Male
;
Rural Population
;
Spouses
7.Erratum: Is the Relationship between Depression and C Reactive Protein Level Moderated by Social Support in Elderly?-Korean Social Life, Health, and Aging Project (KSHAP)
Nam Wook HUR ; Hyeon Chang KIM ; Linda WAITE ; Yoosik YOUM
Psychiatry Investigation 2019;16(8):631-631
The acknowledgements was incorrect in the original publication of this article.
8.Surface roughness and color stability of various composite resins.
Sung Yi LEE ; Hyeon Cheol KIM ; Bock HUR ; Jeong Kil PARK
Journal of Korean Academy of Conservative Dentistry 2007;32(6):542-549
The purpose of this study was to evaluate the difference in the surface roughness after polishing and to evaluate the difference in color stability after immersion in a dye solution among four types of composite resin materials. Four light-polymerized composite resins (Shade A2) with different sized filler content (a nanofilled, a hybrid, a microfilled, a flowble) were used. Average surface roughness (Ra) was measured with a surface roughness tester (Surftest Formtracer) before and after polishing with aluminum oxide abrasive discs (Super-Snap). Color of specimens before and after staining with 2% methylene blue solution were measured using spectrophotometer (CM-3700d) with SCI geometries. The results of Ra and DeltaE were analyzed by one-way analysis of variance (ANOVA), a Scheffe multiple comparison test and Student t-test (p = 0.05). After polishing, Ra values were decreased regardless of type of composite resins. In surface roughness after polishing and color stability after staining, nanofilled composite resin was not different with other composite resins except flowable resins.
Aluminum Oxide
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Composite Resins*
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Humans
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Immersion
;
Methylene Blue
;
Silicone Elastomers
9.Comparison of shaping ability using various Nickel-Titanium rotary files and hybrid technique.
Jung Won KIM ; Jeong Kil PARK ; Bock HUR ; Hyeon Cheol KIM
Journal of Korean Academy of Conservative Dentistry 2007;32(6):530-541
Currently, various Nickel-Titanium rotary files are used in endodontic treatment, but there is no one perfect system that can be applied to any clinical situation. Therefore, the combined uses of various file systems which can emphasize the advantages of each system are introduced as hybrid instrumentation. The ProTaper system is efficient in body shaping and apical pre-enlargement but is reported to have more possibility of transportation and produce more aberrations and deformation in more or less severe curved canals. Recently, new ProTaper system (ProTaper Universal) with different configuration and cross-sectional design to overcome the week points of ProTaper have been marketed. The purpose of this study was to compare and evaluate the shaping abilities of ProTaper, ProTaper Universal system, and two hybrid methods using S-series of ProTaper Universal and Hero Shaper or ProFile. The time lapses for instrumentation were measured and the used files were inspected for distortion. The pre- and post-instrumented root canals were scanned and superimposed to evaluate the aberrations and reduction of root canal curvature and change of radius of canal curvature. The increased canal width and apical centering ratio were calculated at 1, 2, 3, 4 and 5 mm levels from apical foramen. Under the conditions of this study, the ProTaper Universal seems to have better shaping ability than ProTaper in terms of instrumented width and instrumentation time. It may be suggested that the ProTaper Universal system is efficient as much as hybrid instrumentation using ProTaper and other constant-tapered NiTi file systems in highly experienced operators.
Dental Pulp Cavity
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Radius
;
Tooth Apex
;
Transportation
;
Two-Hybrid System Techniques
10.Comparison of apical sealing ability of continuous wave of obturation technique using EndoTwinn and System B.
Hyun Ju SHIN ; Jeong Kil PARK ; Bock HUR ; Hyeon Cheol KIM
Journal of Korean Academy of Conservative Dentistry 2007;32(6):522-529
The purpose of this study was to compare the apical leakage of the root canal filled with the System B and the EndoTwinn (the combined application of heat and ultrasonic vibration). Sixty extracted premolars with straight root were cleaned and shaped to size 35. Group SB was obturated using System B and Group ET was filled with EndoTwinn. A size 35 of 0.06 tapered gutta- percha and Adseal were used and the plugger which could be introduced to 4 mm short of working length was selected in the obturation procedure. As the positive control, Group PC was not filled. In Group SB, ET and PC, all external surfaces of each tooth were coated with nail varnish leaving only 1 mm area around the apical foramen. In the negative control of Group NSB and Group NET, all of external tooth surface including apical foramen was coated with the nail varnish. The specimens were immersed in methylene blue dye solution for 2 days. Then the specimens were sectioned at each 1 mm from apex to 5 mm level. The final score of one specimen was given by summing up of the points at all levels. The dye leakage of Group ET was significantly less than that observed in Group SB (p < 0.05). And the frequency of gutta-percha pulling out from root canal when the plugger was removed was more often with the System B than with EndoTwinn but there was no significant difference.
Bicuspid
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Dental Pulp Cavity
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Gutta-Percha
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Hot Temperature
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Methylene Blue
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Paint
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Tooth
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Tooth Apex
;
Ultrasonics