Publications by authors named "WonJung Choi"

: Osteoporosis is prevalent in patients with chronic kidney disease (CKD), with risk increasing as CKD progresses, subsequently elevating fracture risk. While previous studies have shown a link between low skeletal muscle mass and osteoporosis in the general population, there is limited research exploring this relationship in patients with advanced CKD (stages 3-5D). This study aimed to evaluate whether skeletal muscle area (SMA), as measured by abdominal CT, is correlated with bone mineral density (BMD) in advanced CKD patients beginning hemodialysis.

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Hydrate-based desalination (HBD) shows promise as a freshwater production technology for saline water. Liquid-phase hydrate formers, with their ability to facilitate hydrate formation at atmospheric pressure, have gained attention for their high energy efficiency in HBD. This study explored cyclopentane (CP) HBD by experimentally measuring the thermodynamic properties of CP hydrate in saline solutions and developing a theoretical framework to estimate the water yield of CP HBD under various operating conditions.

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Introduction: Long-term complications of chronic hepatitis B (CHB) viral infection, such as cirrhosis, hepatocellular carcinoma (HCC), and liver failure, cause a large disease burden. This study aimed to describe the epidemiology, clinical outcomes, and treatment patterns of CHB infection and co-infection with hepatitis D virus (HDV) in South Korea.

Methods: The retrospective, observational study used existing data from the Health Insurance Review and Assessment Service (HIRA) database.

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Electrocatalytic advanced oxidation processes have long been considered among of the most viable ways to remediate aquatic contaminants, including As(III). Although direct electrochemical oxidation of As(III) is thermochemically facile, a high reaction rate is not easily achieved because of the competitive oxygen evolution reaction (OER), particularly at high potentials. This study examines the effect of three halides (Cl, Br, and I) on the electrochemical oxidation of As(III) with nanoparticulate TiO electrodes in an aqueous bicarbonate solution at pH 8.

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In this study, the thermodynamic and structural characteristics of natural gas hydrates (NGHs) retrieved from gas hydrate mounds (ARAON Mound 03 (AM03) and ARAON Mound 06 (AM06)) in the Chukchi Sea in the Arctic region were investigated. The gas compositions, crystalline structure, and cage occupancy of the NGHs at AM03 and AM06 were experimentally measured using gas chromatography (GC), C nuclear magnetic resonance (NMR), Raman spectroscopy, and powder X-ray diffraction (PXRD). In the NGHs from AM03 and AM06, a significantly large fraction of CH (> 99%) and a very small amount of HS were enclathrated in small (5) and large (56) cages of sI hydrate.

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In this study, a new sI-sII dual hydrate former [chlorodifluoromethane (CHClF2); an important greenhouse gas with a global warming potential of 1810], which forms sI hydrate by itself and forms sII hydrate in the presence of external help guests such as CH4 and N2, was introduced and closely investigated for its potential significance in gas hydrate-based gas separation. The phase equilibria of CHClF2 hydrate, binary CHClF2 (5%) + N2 (95%) hydrate, and binary CHClF2 (5%) + CH4 (95%) hydrate were measured to examine the formation conditions and thermodynamic stability regions of CHClF2 + external guest hydrates. Nuclear magnetic resonance and in situ Raman spectroscopic results confirmed the formation of sII hydrates for CHClF2 + external guest (N2 or CH4) mixtures.

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Hydrate-based desalination (HBD), a type of freezing-based desalination, can concentrate salts of saline water and produce fresh water via hydrate crystal formation. In this study, the thermodynamic stability, crystallographic information, and kinetic growth behavior of HFC-152a hydrate were investigated to estimate the desalination efficiency of HBD. The phase equilibria revealed that the HFC-152a hydrate could be formed at a higher temperature in the presence of NaCl (0 wt%, 3.

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We compared the efficacy and safety of transcranial direct current stimulation (tDCS) vs. Sertraline in the treatment of Major Depressive Disorder (MDD) in South Korean participants. This was a multi-center, double blind, active controlled study with non-inferiority testing.

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This study investigated the structural transformation, guest distributions, and the extent of replacement in CH + CH-flue gas replacement occurring in sII hydrates via gas chromatography, NMR spectroscopy, and powder X-ray diffraction (PXRD). Simulated flue gas (CO (20%) + N (80%)) was injected into an sII CH (90%) + CH (10%) hydrate for guest exchange. The extent of replacement occurring in CH + CH-flue gas replacement was much lower than that of CH + CH-CO replacement.

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Background: The cost-effectiveness of both cholinesterase inhibitors and memantine by delaying nursing home placement has been supported by numerous studies. The importance of sustained pharmacological treatment in dementia has been relatively less recognized by public health policies compared to early diagnosis. We investigated the effect of the drug (donepezil, rivastigmine, galantamine, and memantine) compliance on the health care costs in newly-diagnosed dementia.

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A 68-year-old man presented at the emergency room with sudden blindness. The day before, he had eaten sashimi and eel and drank alcohol for dinner. He experienced nausea, vomiting, and dizziness afterward.

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This study aimed to evaluate the psychological distress and associated risk factors for distress among patients with gastric epithelial neoplasm undergoing endoscopic submucosal dissection (ESD).A total of 91 patients treated with ESD for gastric epithelial neoplasm between May 2015 and June 2016 were prospectively enrolled. Sociodemographic factors, psychological distress, anxiety, depression, stress, and associated risk factors for psychological distress were evaluated the day before ESD.

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Background: Delirium is common among intensive care unit (ICU) patients, so recent clinical guidelines recommended routine delirium monitoring in the ICU. But, its effect on the patient's clinical outcome is still controversial. In particular, the effect of systems that inform the primary physician of the results of monitoring is largely unknown.

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Objectives: Hyperprolactinemia is an important but often overlooked adverse effect of antipsychotics. Several studies have shown that switching to or adding aripiprazole normalizes antipsychotic-induced hyperprolactinemia. However, no study has directly compared the effectiveness and safety of the 2 strategies.

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Objective: The present study investigates the incidence of psychiatric disorders, related risk factors, and the use of mental health services among people newly diagnosed with one of five major cancers (stomach, liver, colorectal, lung, and breast cancer) based on national registry data from the National Health Insurance Service (NHIS) in the Korean population.

Methods: We collected data on people newly diagnosed with one of the five major cancers between 2005 and 2008 using the nationwide claims data and cancer registration files of the NHIS. We analyzed the data of those diagnosed with psychiatric disorders over a 5-year period, from 2004 to 2009.

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Objective: Although self-esteem is thought to be an important psychological factor in bipolar disorder, little is known about implicit and explicit self-esteem in manic patients. In this study, we investigated differences in implicit and explicit self-esteem among bipolar manic patients, bipolar euthymic patients, and healthy controls using the Implicit Association Test (IAT).

Methods: Participants included 19 manic patients, 27 euthymic patients, and 27 healthy controls.

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Background: Most previous studies on the efficacy of antipsychotic medication for the treatment of delirium have reported that there is no significant difference between typical and atypical antipsychotic medications. It is known, however, that older age might be a predictor of poor response to antipsychotics in the treatment of delirium. The objective of this study was to compare the efficacy and safety of haloperidol versus three atypical antipsychotic medications (risperidone, olanzapine, and quetiapine) for the treatment of delirium with consideration of patient age.

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Purpose: Previous studies have reported that over a third of cancer patients experience significant psychological distress with diagnosis and treatment of cancer. Mental adjustment to cancer as well as other biologic and demographic factors may be associated with their distress. We investigated the relationship between mental adjustment and distress in patients with thyroid cancer prior to thyroidectomy.

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Background/aims: We made a systematic review and evaluation of endoscopic cryotherapy of endobronchial tumors, investigating safety and efficacy.

Methods: Qualified studies regarding endoscopic cryotherapy of lung tumors were systemically evaluated using available databases according to predefined criteria.

Results: In total, 16 publications were included in the final assessment.

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Objectives: To estimate the medical expenditure associated with osteoporotic hip fracture in elderly Korean women from insurer's perspective.

Methods: All claim records of women aged > or =50 years and diagnosed with hip fracture from 2002 to 2004 were obtained from the Korean National Health Insurance. The first 6 months were considered a "window period" during which patients with fractures were defined as incident cases if their initial records of visit or admission were observed after June 30, 2002.

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Background: The lack of epidemiologic information on osteoporotic hip fractures hampers the development of preventive or curative measures against osteoporosis in South Korea. We conducted a population-based study to estimate the annual incidence of hip fractures. Also, we examined factors associated with post-fracture mortality among Korean elderly to evaluate the impact of osteoporosis on our society and to identify high-risk populations.

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Objectives: To estimate the economic burden of osteoporotic vertebral fracture (VF) from a societal perspective.

Methods: From 2002 to 2004, we identified all National Health Insurance claims records for women >or= 50 years old with a diagnosis of VF. The first 6-months was defined as a "clearance period," Ysuch that patients were considered as incident cases if their first claim of fracture was recorded after June 30, 2002.

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