1.Biofilm three-dimensional architecture influences in situ pH distribution pattern on the human enamel surface
Xiao JIN ; Hara T ANDERSON ; Kim DONGYEOP ; Zero T DOMENICK ; Koo HYUN ; Hwang GEELSU
International Journal of Oral Science 2017;9(2):74-79
To investigate how the biofilm three-dimensional (3D) architecture influences in situ pH distribution patterns on the enamel surface. Biofilms were formed on human tooth enamel in the presence of 1% sucrose or 0.5%glucose plus 0.5%fructose. At specific time points, biofilms were exposed to a neutral pH buffer to mimic the buffering of saliva and subsequently pulsed with 1% glucose to induce re-acidification. Simultaneous 3D pH mapping and architecture of intact biofilms was performed using two-photon confocal microscopy. The enamel surface and mineral content characteristics were examined successively via optical profilometry and microradiography analyses. Sucrose-mediated biofilm formation created spatial heterogeneities manifested by complex networks of bacterial clusters (microcolonies). Acidic regions (pH<5.5) were found only in the interior of microcolonies, which impedes rapid neutralization (taking more than 120 min for neutralization). Glucose exposure rapidly re-created the acidic niches, indicating formation of diffusion barriers associated with microcolonies structure. Enamel demineralization (white spots), rougher surface, deeper lesion and more mineral loss appeared to be associated with the localization of these bacterial clusters at the biofilm-enamel interface. Similar 3D architecture was observed in plaque-biofilms formed in vivo in the presence of sucrose. The formation of complex 3D architectures creates spatially heterogeneous acidic microenvironments in close proximity of enamel surface, which might correlate with the localized pattern of the onset of carious lesions (white spot like) on teeth.
2.Additions to the Knowledge of the Fungal Order Eurotiales in Korea:Eight Undescribed Species
Thuong T. T. NGUYEN ; Ki Hyun KANG ; Dong Hee KIM ; Su Jin KIM ; Hye Yeon MUN ; Wonsu CHEON ; Hyang Burm LEE
Mycobiology 2023;51(6):417-435
Eurotiales is a relatively large order of Ascomycetes, well-known for their ability to produce secondary metabolites with potential beneficial applications. To understand their diversity and distribution, different environmental sources including soil, freshwater, insect, and indoor air were investigated. Eight strains of Eurotiales were isolated and identified based on their morphological characters and a multi-gene phylogenetic analysis of the ITS, BenA, CaM, and RPB2 regions. We identified eight taxa that were previously not reported from Korea: Aspergillus baeticus, A. griseoaurantiacus, A. spinulosporus, Penicillium anthracinoglaciei, P. labradorum, P.nalgiovense, Talaromyces atroroseus, and T. georgiensis. Detailed descriptions, illustrations, and phylogenetic tree for the eight new records species are presented, and information regarding the records is also discussed.
3.High-content analysis of in vitro hepatocyte injury induced by various hepatotoxicants
Nga T T THAM ; So Ryeon HWANG ; Ji Hyun BANG ; Hee YI ; Young Il PARK ; Seok Jin KANG ; Hwan Goo KANG ; Yong Sang KIM ; Hyun Ok KU
Journal of Veterinary Science 2019;20(1):34-42
In vitro prediction of hepatotoxicity can enhance the performance of non-clinical animal testing for identifying chemical hazards. In this study, we assessed high-content analysis (HCA) using multi-parameter cell-based assays as an in vitro hepatotoxicity testing model using various hepatotoxicants and human hepatocytes such as HepG2 cells and human primary hepatocytes (hPHs). Both hepatocyte types were exposed separately to multiple doses of ten hepatotoxicants associated with liver injury whose mechanisms of action have been described. HCA data were obtained using fluorescence probes for nuclear size (Hoechst), mitochondrial membrane potential (TMRM), cytosolic free calcium (Fluo-4AM), and lipid peroxidation (BODIPY). Cellular alterations were observed in response to all hepatotoxicants tested. The most sensitive parameter was TMRM, with high sensitivity at a low dose, next was BODIPY, followed by Fluo-4AM. HCA data from HepG2 cells and hPHs were generally concordant, although some inconsistencies were noted. Both hepatocyte types showed mild or severe mitochondrial impairment and lipid peroxidation in response to several hepatotoxicants. The results demonstrate that the application of HCA to in vitro hepatotoxicity testing enables more efficient hazard identification, and further, they suggest that certain parameters could serve as sensitive endpoints for predicting the hepatotoxic potential of chemical compounds.
Animals
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Calcium
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Cytosol
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Fluorescence
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Hep G2 Cells
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Hepatocytes
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Humans
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In Vitro Techniques
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Lipid Peroxidation
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Liver
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Membrane Potential, Mitochondrial
4.Subtyping of Ischemic Stroke Based on Vascular Imaging: Analysis of 1,167 Acute, Consecutive Patients.
Jin T KIM ; Sung H YOO ; Jee Hyun KWON ; Sun U KWON ; Jong S KIM
Journal of Clinical Neurology 2006;2(4):225-230
BACKGROUND AND PURPOSE: Knowledge of a patient's cerebral vascular status is essential for accurately classifying stroke. However, vascular evaluations have been incomplete in previous studies, and a stroke registry based on the results of such vascular investigations has not been reported. The purpose of the present study was to classify ischemic strokes based on vascular imaging data. METHODS: Between May 2001 and August 2003, 1,264 patients with acute (< 7 days) ischemic stroke were admitted to Asan Medical Center. Among them, 1,167 patients (750 men and 417 women; mean age 63.3 years) underwent an angiogram (mostly a magnetic resonance angiogram) and were included in this study. Electrocardiography and computed tomography/magnetic resonance imaging were performed in all patients, while 31.2% underwent echocardiography. The subtypes were categorized with the aid of a modification of the Trial of ORG 10172 in the Acute Stroke Treatment classification. RESULTS: Large-artery atherosclerosis (LAA) was the most frequent subtype (42%), followed by small-vessel occlusion (SVO, 27%), cardiogenic embolism (CE, 15%), undetermined etiology (15%), and other determined etiology (1.5%). Risk factors included hypertension (71%), cigarette smoking (35%), diabetes mellitus (30%), history of previous stroke (22.7%), emboligenic cardiac diseases (20%), and hypercholesterolemia (11%). Hypertension was more common in patients with SVO than in those with other subtypes (p<0.05), and the case-fatality rate was higher in patients with CE than in those with other subtypes (p<0.01). The functional outcome was worse in patients with LAA than in those with other stroke subtypes (p<0.01). CONCLUSION: According to the stroke registry based on vascular imaging results, LAA was the most common stroke subtype followed by SVD. The high incidence of LAA is probably related to the increased identification of the presence of intracranial atherosclerosis by MR angiogram.
Atherosclerosis
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Chungcheongnam-do
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Classification
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Diabetes Mellitus
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Diagnosis
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Echocardiography
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Electrocardiography
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Embolism
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Female
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Heart Diseases
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Humans
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Hypercholesterolemia
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Hypertension
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Incidence
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Intracranial Arteriosclerosis
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Male
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Risk Factors
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Smoking
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Stroke*
5.The International Association for the Study of Lung Cancer Lymph Node Map: A Radiologic Atlas and Review.
Jin Hwan KIM ; Edwin J R VAN BEEK ; John T MURCHISON ; Aleksander MARIN ; Saeed MIRSADRAEE
Tuberculosis and Respiratory Diseases 2015;78(3):180-189
Accurate lymph node staging of lung cancer is crucial in determining optimal treatment plans and predicting patient outcome. Currently used lymph node maps have been reconciled to the internationally accepted International Association for the Study of Lung Cancer (IASLC) map published in the seventh edition of TNM classification system of malignant tumours. This article provides computed tomographic illustrations of the IASLC nodal map, to facilitate its application in day-to-day clinical practice in order to increase the appropriate classification in lung cancer staging.
Classification
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Humans
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Lung Neoplasms*
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Lymph Nodes*
;
Neoplasm Staging
6.Improving Access to Mental Health Services for Korean American Immigrants: Moving Toward a Community Partnership Between Religious and Mental Health Services.
Hochang B LEE ; Jennifer A HANNER ; Seong Jin CHO ; Hae Ra HAN ; Miyong T KIM
Psychiatry Investigation 2008;5(1):14-20
Korean Americans (KAs) with psychiatric service needs underutilizes the mainstream mental health services in United States (US). Barriers to mental health service access among KAs reflect their unique heritage and culture. More than two-thirds of KAs identify themselves as Christians, and Korean clergy have influential roles in daily lives of vast majority of KAs. By working with the Korean clergy, a small voluntary organization such as the Association of Korean American Psychiatrists could provide invaluable assistance in removing the barriers to mental health services for KAs.
Asian Americans*
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Clergy
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Emigrants and Immigrants*
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Emigration and Immigration
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Humans
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Mental Health Services*
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Psychiatry
;
United States
7.An empirical evaluation of electronic annotation tools for Twitter data
Davy WEISSENBACHER ; Karen O'CONNOR ; Aiko T. HIRAKI ; Jin-Dong KIM ; Graciela GONZALEZ-HERNANDEZ
Genomics & Informatics 2020;18(2):e24-
Despite a growing number of natural language processing shared-tasks dedicated to the use of Twitter data, there is currently no ad-hoc annotation tool for the purpose. During the 6th edition of BLAH, after a short review of 19 generic annotation tools, we adapted GATE and TextAE for annotating Twitter timelines. Although none of the tools reviewed allow the annotation of all information inherent of Twitter timelines, a few may be suitable provided the willingness by annotators to compromise on some functionality.
8.An empirical evaluation of electronic annotation tools for Twitter data
Davy WEISSENBACHER ; Karen O'CONNOR ; Aiko T. HIRAKI ; Jin-Dong KIM ; Graciela GONZALEZ-HERNANDEZ
Genomics & Informatics 2020;18(2):e24-
Despite a growing number of natural language processing shared-tasks dedicated to the use of Twitter data, there is currently no ad-hoc annotation tool for the purpose. During the 6th edition of BLAH, after a short review of 19 generic annotation tools, we adapted GATE and TextAE for annotating Twitter timelines. Although none of the tools reviewed allow the annotation of all information inherent of Twitter timelines, a few may be suitable provided the willingness by annotators to compromise on some functionality.
9.Efficacy and safety of alirocumab in Korean patients with hypercholesterolemia and high cardiovascular risk: subanalysis of the ODYSSEY-KT study
Chang Wook NAM ; Dong Soo KIM ; Jianyong LI ; Marie T BACCARA-DINET ; Ivy LI ; Ji Hyun KIM ; Chong Jin KIM
The Korean Journal of Internal Medicine 2019;34(6):1252-1262
BACKGROUND/AIMS:
Efficacy and safety data of alirocumab, a fully human monoclonal antibody to proprotein convertase subtilisin/kexin type 9 (PCSK9), is not yet well established in the Korean population. We assessed them in ODYSSEY-KT through the pre-specified Korean subanalysis.
METHODS:
In the ODYSSEY-KT study, South Korean and Taiwanese patients with hypercholesterolemia and high cardiovascular risks were randomized (1:1) to alirocumab or placebo. Alirocumab was self-administered subcutaneously at 75 mg every 2 weeks with a maximally tolerated statin dose with or without other lipid-modifying therapies. Alirocumab dose was increased to 150 mg every 2 weeks at week 12 if low density lipoprotein cholesterol (LDL-C) ≥ 70 mg/dL at week 8. Primary endpoint was percent change in LDL-C from baseline to week 24. Results from Korean cohort (n = 83: 40 for alirocumab and 43 for placebo, respectively) analyses are reported here.
RESULTS:
In alirocumab group, the least square of mean change percent in LDL-C levels was –65.7% (placebo: 11.1%; p < 0.0001) and 92.0% of them achieved LDL-C < 70 mg/dL (placebo: 12.7%; p < 0.0001) at week 24. Alirocumab also showed significantly greater improvements in high density lipoprotein cholesterol (HDL-C), non-HDL-C, total cholesterol, lipoprotein(a), and apolipoprotein B than placebo (p < 0.05). Two consecutive calculated LDL-C values < 25 mg/dL were observed in 37.5% of alirocumab-treated patients. Overall, 45.0% alirocumab-treated and 51.2% placebo-treated patients experienced treatment-emergent adverse events (TEAEs) without discontinuation of treatment due to TEAEs.
CONCLUSIONS
Alirocumab has demonstrated to be effective in improvement of LDL-C and related lipid profiles in Korean cohort. Alirocumab was generally well tolerated with no significant safety signals.
10.Analysis of Etiology and Prognosis of Pulmonary Complications in Children with Hematological or Oncological Disorders in Pediatric Intensive Care Unit.
Jin Young JUNG ; Soo Jong HONG ; Young Jun AN ; Ja Hyung KIM ; Jong Jin SEO ; Hyung Nam MOON ; Thad T GHIM
Journal of the Korean Pediatric Society 2002;45(8):1000-1006
PURPOSE: In the course of treatment, patients with hematological or oncological disorders often develop pulmonary complication. The patients who develop a severe pulmonary complication have a poor outlook. The causes of pulmonary complication are either infectious or non-infectious in origin. We have analyzed the etiology and outcome of these patients admitted to the pediatric intensive care unit of Asan Medical Center. METHODS: Medical records of 95 patients on Pediatric oncology service who were admitted to pediatric intensive care unit(PICU) of Asan Medical Center from Jan 1997 to May 2000 were retrospectively reviewed. RESULTS: The mean age of the patients was 8.5 years(2 months-18 years). The underlying malignancies of these 95 patients were as following; acute lymphoblastic leukemia(31 cases), lymphoma (11 cases), acute myeloid leukemia(nine cases), brain tumor(eight cases) and other solid tumors(25 cases). Pulmonary complications included pneumonia, acute respiratory failure, pneumothorax and pleural effusion. The most common cause of pulmonary complication was infection(88%) in etiology. The overall mortality rate was 56.8%. Pulmonary complications in these patients carried high rates of mortality regardless of whether they were immune compromised(76%) or not(69%). Even without pulmonary complications, the hematological or oncological patients admitted to PICU had high mortality rates of 43%. CONCLUSION: Pulmonary complications are frequent finding in the hematological or oncological patients admitted to Intensive Care Unit. The main etiology of these pulmonary complications was infection, which carried a high mortality rate regardless of their immune status at the time when they were admitted to PICU
Brain
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Child*
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Chungcheongnam-do
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Humans
;
Intensive Care Units*
;
Critical Care*
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Lymphoma
;
Medical Records
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Mortality
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Pleural Effusion
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Pneumonia
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Pneumothorax
;
Prognosis*
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Respiratory Insufficiency
;
Retrospective Studies