1.Electron and Light Microscopic Studies on the Development of Oidia from Somatic Mycelium of Coprinus cinereus.
Mycobiology 2004;32(4):164-169
Development of oidia, a type of thallic spores from monokaryotic mycelium of Coprinus cinereus was examined with electron microscope and light microscopes. Oidia formation in this fungus is unique in its mode of formation compared with other types of asexual sporogenesis. Oidiogenesis in C. cinereus is carried out in three steps: 1) Formation of oidiophore from the parent mycelium, 2) Formation of initials of oidial cells from swollen oidiophore, 3) Segmentation and detachment of mature oidial cell. Oidiophores appear to spring out singly as a swollen hyphal branches from the normal foot hyphae or sometimes coiled hypha. From the oidiophore, oidial branches sprout out forming a group of 2~6, most often 4 oidial cells and each oidial cell undergoes a single mitosis resulting in 2 oidia. One of the sibling oidial cells in a group is frequently transformed into a new oidiophore, thus oidiogenic structures are tandemly produced at the several different levels.
Coprinus*
;
Foot
;
Fungi
;
Humans
;
Hyphae
;
Mitosis
;
Mycelium*
;
Parents
;
Siblings
;
Spores
2.Clinical Outcomes After Silicone Oil Removal.
Jin Sook YOON ; Soo Young LEE ; S C LEE ; Oh Woong KWON
Journal of the Korean Ophthalmological Society 2003;44(3):642-648
PURPOSE: To evaluate clinical outcomes after silicone oil removal, we analyzed retinal redetachment, visual acuity, and postoperative complications. METHODS: 73 consecutive eyes who underwent silicone oil removal were studied in a retrospective fashion. 41 eyes with proliferative vitreoretinopathy, 20 eyes with proliferative diabetic retinopathy, 6 eyes with traumatic detachment, 6 eyes with high myopic macular hole were included. In addition to anatomic and visual results, associated complications were assessed. RESULTS: Anatomic success rate was 90.4% in 73 eyes. 64 eyes achieved attachment after oil injection combined vitrectomy and 8 of 64 eyes (12.5%) were redetached after oil removal. 37 eyes of the 64 eyes (57.8%) had an increase in visual acuity at least one Snellen line after oil removal. Glaucoma (21.9%), keratopathy (8.2%) and cataract (9.5%) were the complications. The mean duration of oil tamponade of detached group was 7.75 months and that of attached group was 7.14 months and there were no siginificant difference between two groups(P>0.05). CONCLUSIONS: The duration of the silicone oil tamponade had no siginificant effect on the redetachment rate. We recommend not to apply standard criteria for timing of silicone oil removal, but to decide individually, considering underlying disease and complications.
Cataract
;
Diabetic Retinopathy
;
Glaucoma
;
Postoperative Complications
;
Retinal Perforations
;
Retinaldehyde
;
Retrospective Studies
;
Silicone Oils*
;
Visual Acuity
;
Vitrectomy
;
Vitreoretinopathy, Proliferative
3.Difference in the Location and Risk Factors of Cerebral Microbleeds According to Ischemic Stroke Subtypes.
Bum Joon KIM ; Youngshin YOON ; Hoyon SOHN ; Dong Wha KANG ; Jong S KIM ; Sun U KWON
Journal of Stroke 2016;18(3):297-303
BACKGROUND AND PURPOSE: The location of cerebral microbleeds (CMBs) may differ according to ischemic stroke subtype, and the underlying pathomechanism may differ by their location. Here, we investigated the characteristics of CMBs according to various ischemic stroke subtypes to verify this issue. METHODS: Patients with acute ischemic stroke were consecutively included. The presence of CMBs was determined by gradient echo image sequence. The distribution of CMBs was classified as deep, lobar, or diffuse (both deep and lobar). The prevalence, risk factors, and distribution of CMBs were compared among patients with different stroke subtypes. Factors associated with the distribution of CMBs were investigated. RESULTS: Among the 1033 patients included in this study, ischemic stroke subtypes were classified as large artery atherosclerosis (LAA; n=432), small vessel occlusion (SVO; n=304), and cardioembolism (CE; n=297). The prevalence of CMBs was highest in patients with SVO (40.5%), followed by CE (33.0%) and LAA (24.8%; P<0.001). The locations of CMBs was different according to subtype (P=0.004). CE [odds ratio (OR)=1.85 (1.02-3.34); P=0.042] and the use of antithrombotics [OR=1.80 (1.10-2.94); P=0.019] were associated with lobar CMBs, and old age [OR=1.02 (1.00-1.04); P=0.015] and hypertension [OR=1.61 (1.08-2.40); P=0.020] were associated with deep CMBs. CONCLUSIONS: CMBs were frequently located in the lobar area in patients with CE. Previous use of antithrombotic agents is associated with lobar CMBs. The pathogenic mechanism of CMB may differ according to ischemic stroke subtype and location.
Arteries
;
Atherosclerosis
;
Classification
;
Fibrinolytic Agents
;
Humans
;
Hypertension
;
Prevalence
;
Risk Factors*
;
Stroke*
4.Serum Uric Acid is Associated with Cardiovascular Events in Patients with Coronary Artery Disease.
Jang Ho BAE ; Dae Woo HYUN ; Taek Geun KWON ; Hyun Ju YOON ; Amir LERMAN ; Charanjit S RIHAL
Korean Circulation Journal 2007;37(4):161-166
BACKGROUND AND OBJECTIVES: Whether uric acid is a predictor of cardiovascular events remains controversial. We sought to evaluate the effects of the serum uric acid levels on major adverse cardiovascular events (MACEs) in the patients with coronary artery disease (CAD). SUBJECTS AND METHODS: The study population consisted of 660 consecutive patients with CAD, and they were followed up for a mean of 27 months (maximum: 62 months). The recorded MACEs included acute myocardial infarction (AMI), stroke, coronary artery bypass graft, percutaneous coronary intervention (PCI) due to de novo lesion during follow up, congestive heart failure (CHF) and sudden cardiac death. RESULTS: In the CAD patients with a uric acid level < or =3.88 mg/dL (the lowest quartile), as compared with those CAD patients with uric acid levels >5.74 mg/dL (the highest quartile), the MACE rate increased from 7.2% to 20.1%. On univariate Cox regression analysis, the highest uric acid quartile was a predictor of AMI, CHF and MACE. The absolute serum uric acid level was predictive of PCI, CHF and MACE. Multivariate Cox regression analysis showed that the independent predictors of MACE were presentation with acute coronary syndrome (HR 1.70, 95% CI: 1.04 to 2.78, p=0.033), multi-vessel disease (HR 2.43, 95% CI: 1.44 to 4.12, p=0.001), and the uric acid levels (HR 1.22, 95% CI: 1.05 to 1.43, p=0.010), and the highest uric acid quartile (HR 2.54, 95% CI: 1.58 to 4.10, p<0.001). CONCLUSION: The serum uric acid level and multi-vessel disease are associated with subsequent cardiovascular events in the patients with CAD.
Acute Coronary Syndrome
;
Coronary Artery Bypass
;
Coronary Artery Disease*
;
Coronary Vessels*
;
Death, Sudden, Cardiac
;
Follow-Up Studies
;
Heart Failure
;
Humans
;
Myocardial Infarction
;
Percutaneous Coronary Intervention
;
Prognosis
;
Stroke
;
Transplants
;
Uric Acid*
5.New Oral Anticoagulants May Be Particularly Useful for Asian Stroke Patients.
Oh Young BANG ; Keun Sik HONG ; Ji Hoe HEO ; Jaseong KOO ; Sun U KWON ; Kyung Ho YU ; Hee Joon BAE ; Byung Chul LEE ; Byung Woo YOON ; Jong S KIM
Journal of Stroke 2014;16(2):73-80
Atrial fibrillation (AF) is an emerging epidemic in both high-income and low-income countries, mainly because of global population aging. Stroke is a major complication of AF, and AF-related ischemic stroke is more disabling and more fatal than other types of ischemic stroke. However, because of concerns about bleeding complications, particularly intracranial hemorrhage, and the limitations of a narrow therapeutic window, warfarin is underused. Four large phase III randomized controlled trials in patients with non-valvular AF (RE-LY, ROCKET-AF, ARISTOTLE, and ENGAGE-AF-TIMI 48) demonstrated that new oral anticoagulants (NOACs) are superior or non-inferior to warfarin as regards their efficacy in preventing ischemic stroke and systemic embolism, and superior to warfarin in terms of intracranial hemorrhage. Among AF patients receiving warfarin, Asians compared to non-Asians are at higher risk of stroke or systemic embolism and are also more prone to develop major bleeding complications, including intracranial hemorrhage. The extra benefit offered by NOACs over warfarin appears to be greater in Asians than in non-Asians. In addition, Asians are less compliant, partly because of the frequent use of herbal remedies. Therefore, NOACs compared to warfarin may be safer and more useful in Asians than in non-Asians, especially in stroke patients. Although the use of NOACs in AF patients is rapidly increasing, guidelines for the insurance reimbursement of NOACs have not been resolved, partly because of insufficient understanding of the benefit of NOACs and partly because of cost concerns. The cost-effectiveness of NOACs has been well demonstrated in the healthcare settings of developed countries, and its magnitude would vary depending on population characteristics as well as treatment cost. Therefore, academic societies and regulatory authorities should work together to formulate a scientific healthcare policy that will effectively reduce the burden of AF-related stroke in this rapidly aging society.
Aging
;
Anticoagulants*
;
Asian Continental Ancestry Group*
;
Atrial Fibrillation
;
Delivery of Health Care
;
Developed Countries
;
Embolism
;
Health Care Costs
;
Hemorrhage
;
Humans
;
Insurance
;
Intracranial Hemorrhages
;
Population Characteristics
;
Stroke*
;
Warfarin
6.Hypertension, a Low Ejection Fraction and Severe Angiographic Findings are Associated with Smooth Muscle Dysfunction in Patients with Coronary Atherosclerosis.
Jang Ho BAE ; Charanjit S RIHAL ; Dae Woo HYUN ; Ki Rack PARK ; Taek Geun KWON ; Hyun Ju YOON ; Amir LERMAN
Korean Circulation Journal 2007;37(10):470-474
BACKGROUND AND OBJECTIVES: Nitroglycerin-mediated arterial dilation (NMD) was shown to be preserved in most previous studies, and this is possibly due to using a single high dose of nitroglycerin (NTG), which causes maximal arterial dilation. We sought to evaluate the clinical factors of flow-mediated dilation (FMD) and NMD at different doses of NTG in the patients with coronary artery disease (CAD). SUBJECTS AND METHODS: Thirty-two consecutive patients (mean age: 61 years old, 18 males) with angiographically proven CAD underwent FMD and NMD at total cumulative doses of 25microgram, 175microgram and 325microgram with using high-resolution ultrasound for the imaging. RESULTS: The FMD, NMD (25microgram), NMD (175microgram) and NMD (325microgram) were 4.72+/-1.82%, 7.08+/-3.02%, 13.33+/-6.14% and 15.89+/-7.24%, respectively (p<0.001 compared with each other). Univariate analysis showed that the FMD is associated with the serum homocysteine level, the NMD (25microgram) is associated with the body mass index, the NMD (175microgram) is associated with the fasting blood sugar and the ejection fraction, and the NMD (325microgram) is associated with the fasting blood sugar, while there was no significant difference of the FMD and NMD according to the presence of CAD risk factors. Multivariate analysis disclosed that the independent factors of FMD were the serum homocysteine and triglyceride levels, and those of NMD (25microgram) were hypertension, a low ejection fraction and severe coronary angiographic findings, while there was no independent factor for NMD (175microgram) and NMD (325microgram). CONCLUSION: This study suggests that hypertension, a low ejection fraction and significant stenotic coronary lesion may be associated with endothelium-independent smooth muscle dysfunction at low dose NTG, while the serum homocysteine and triglyceride levels are associated with endothelium-dependent endothelial dysfunction in the patients with CAD. Using low-dose NTG is important when measuring the NMD.
Blood Glucose
;
Body Mass Index
;
Coronary Artery Disease*
;
Endothelium
;
Fasting
;
Homocysteine
;
Humans
;
Hypertension*
;
Middle Aged
;
Multivariate Analysis
;
Muscle, Smooth*
;
Nitroglycerin
;
Risk Factors
;
Triglycerides
;
Ultrasonography
7.A Case of Diphyllobothrium nihonkaiense Infection as Confirmed by Mitochondrial COX1 Gene Sequence Analysis.
Sang Hyun PARK ; Keeseon S EOM ; Min Sun PARK ; Oh Kyoung KWON ; Hyo Sun KIM ; Jai Hoon YOON
The Korean Journal of Parasitology 2013;51(4):471-473
Diphyllobothrium nihonkaiense has been reported in Korea as Diphyllobothrium latum because of their close morphologic resemblance. We have identified a human case of D. nihonkaiense infection using the mitochondrial cytochrome c oxidase subunit I (cox1) gene sequence analysis. On 18 February 2012, a patient who had consumed raw fish a month earlier visited our outpatient clinic with a long tapeworm parasite excreted in the feces. The body of the segmented worm was 2 m long and divided into the scolex (head) and proglottids. It was morphologically close to D. nihonkaiense and D. latum. The cox1 gene analysis showed 99.4% (340/342 bp) homology with D. nihonkaiense but only 91.8% (314/342 bp) homology with D. latum. The present study suggested that the Diphyllobothrium spp. infection in Korea should be analyzed with specific DNA sequence for an accurate species identification.
Animals
;
Cyclooxygenase 1/*genetics
;
Diphyllobothriasis/*parasitology
;
Diphyllobothrium/enzymology/genetics/*isolation & purification
;
Female
;
Helminth Proteins/*genetics
;
Humans
;
Mitochondrial Proteins/*genetics
8.Risk of Vertebral Artery Injury: A Comparison between C2 Subarticular Segmental and C1-2 Transarticular Screws.
Seong Wan KIM ; Jin S YEOM ; Yoon Ju KWON ; Seung Min YOU ; Young Hee AN ; Kun Woo PARK ; Bong Soon CHANG ; Choon Ki LEE
The Journal of the Korean Orthopaedic Association 2008;43(5):572-578
PURPOSE: We compared the risk of vertebral artery injury associated with the insertion of C1-2 transarticular screws and C2 subarticular segmental screws using a computer simulation of computed tomography (CT) scans. MATERIALS AND METHODS: We simulated the placement of C1-2 transarticular screws and C2 subarticular segmental screws using 1-mm interval CT scan images in 166 patients, along with simulation software. We then determined the incidence of violation of the C2 vertebral artery groove. The same determination was performed for high-riding vertebral arteries found among those patients. RESULTS: Among the 332 C2 vertebral artery grooves (166 patients), C1-2 transarticular screws violated the groove in 33 (9.9%) instances, while C2 subarticular segmental screws violated the groove in 19 (5.7%) instances. The difference in incidence between the two screw types was statistically significant (p=0.001, McNemar test). In the 48 high-riding vertebral arteries, C1-2 transarticular screws led to violation of the C2 vertebral artery groove in 30 (62.5%) instances, while C2 subarticular segmental screws led to violation of the groove in 18 (37.5%) instances. The difference in incidence between the two screw types was statistically significant (p=0.002, McNemar test). CONCLUSION: Use of C2 subarticular segmental screws is associated with a lower risk of vertebral artery injury than is the use of C1-2 transarticular screws, even for high-riding vertebral arteries.
Computer Simulation
;
Humans
;
Incidence
;
Vertebral Artery
9.Expression of 4-1BB and 4-1BBL in thymocytes during thymus regeneration.
Young Mi KIM ; Hye Kyung KIM ; Hyo Jin KIM ; Hee Woo LEE ; Seong A JU ; Beom K CHOI ; Byoung S KWON ; Bong Seon KIM ; Jae Bong KIM ; Young Tak LIM ; Sik YOON
Experimental & Molecular Medicine 2009;41(12):896-911
4-1BB, a member of the tumor necrosis factor receptor (TNFR) superfamily, is a major costimulatory receptor that is rapidly expressed on the surface of CD4+ and CD8+ T cells after antigen- or mitogen-induced activation. The interaction of 4-1BB with 4-1BBL regulates immunity and promotes the survival and expansion of activated T cells. In this study, the expression of 4-1BB and 4-1BBL was examined during regeneration of the murine thymus following acute cyclophosphamide-induced involution. Four-color flow cytometry showed that 4-1BB and 4-1BBL were present in the normal thymus and were preferentially expressed in the regenerating thymus, mainly in CD4+CD8+ double-positive (DP) thymocytes. Furthermore, the CD4loCD8lo, CD4+CD8lo and CD4loCD8+ thymocyte subsets, representing stages of thymocyte differentiation intermediate between DP and single-positive (SP) thymocytes, also expressed 4-1BB and 4-1BBL during thymus regeneration but to a lesser degree. Interestingly, the 4-1BB and 4-1BBL positive cells among the CD4+CD8+ DP thymocytes present during thymus regeneration were TCR(hi) and CD69+ unlike the corresponding controls. Moreover, the 4-1BB and 4-1BBL positive cells among the intermediate subsets present during thymus regeneration also exhibited TCRhi/int and CD69+/int phenotypes, indicating that 4-1BB and 4-1BBL are predominantly expressed by the positively selected population of the CD4+CD8+ DP and the intermediate thymocytes during thymus regeneration. RT-PCR and Western blot analyses confirmed the presence and elevated levels of 4-1BB and 4-1BBL mRNA and protein in thymocytes during thymus regeneration. We also found that the interaction of 4-1BB with 4-1BBL promoted thymocyte adhesion to thymic epithelial cells. Our results suggest that 4-1BB and 4-1BBL participate in T lymphopoiesis associated with positive selection during recovery from acute thymic involution.
4-1BB Ligand/genetics/*metabolism
;
Animals
;
Antigens, CD137/genetics/*metabolism
;
CD4-Positive T-Lymphocytes/cytology/metabolism
;
CD8-Positive T-Lymphocytes/cytology/metabolism
;
Cell Adhesion
;
Cell Differentiation
;
Cell Line
;
Cells, Cultured
;
Cyclophosphamide/pharmacology
;
Epithelial Cells/cytology
;
Gene Expression Regulation
;
Immunosuppressive Agents/pharmacology
;
Male
;
Mice
;
Mice, Inbred C57BL
;
RNA, Messenger/genetics
;
*Regeneration
;
T-Lymphocytes/*cytology/metabolism
;
Thymus Gland/*cytology/drug effects/*physiology
10.Stroke Statistics in Korea: Part I. Epidemiology and Risk Factors: A Report from the Korean Stroke Society and Clinical Research Center for Stroke.
Keun Sik HONG ; Oh Young BANG ; Dong Wha KANG ; Kyung Ho YU ; Hee Joon BAE ; Jin Soo LEE ; Ji Hoe HEO ; Sun U KWON ; Chang Wan OH ; Byung Chul LEE ; Jong S KIM ; Byung Woo YOON
Journal of Stroke 2013;15(1):2-20
The aim of the Part I of Stroke Statistics in Korea is to summarize nationally representative data of the epidemiology and risk factors of stroke in a single document. Every year, approximately 105,000 people experience a new or recurrent stroke and more than 26,000 die of stroke, which indicates that every 5 minutes stroke attacks someone and every 20 minutes stroke kills someone in Korea. Stroke accounts for roughly 1 of every 10 deaths. The estimated stroke prevalence is about 795,000 in people aged > or =30 years. The nationwide total cost for stroke care was 3,737 billion Korean won (US$3.3 billion) in 2005. Fortunately, the annual stroke mortality rate decreased substantially by 28.3% during the first decade of the 21th century (53.2/100,000 in 2010). Among OECD countries, Korea had the lowest in-hospital 30-day case-fatality rate for ischemic stroke and ranked third lowest for hemorrhagic stroke in 2009. The proportion of ischemic stroke has steadily increased and accounted for 76% of all strokes in 2009. According to hospital registry studies, the 90-day mortality rate was 3-7% for ischemic stroke and 17% for intracerebral hemorrhage. For risk factors, among Korean adults > or =30 years of age, one in 3-4 has hypertension, one in 10 diabetes, and one in 7 hypercholesterolemia. One in 3 Korean adults > or =19 years of age is obese. Over the last 10 years, the prevalence of hypertension slightly decreased, but the prevalence of diabetes, hypercholesterolemia, and obesity increased. Smoking prevalence in men has decreased, but is still as high as 48%. This report could be a valuable resource for establishing health care policy and guiding future research directions.
Adult
;
Aged
;
Cerebral Hemorrhage
;
Delivery of Health Care
;
Humans
;
Hypercholesterolemia
;
Hypertension
;
Korea
;
Male
;
Obesity
;
Prevalence
;
Risk Factors
;
Smoke
;
Smoking
;
Stroke