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1.
Inorg Chem ; 63(1): 537-547, 2024 Jan 08.
Article in English | MEDLINE | ID: mdl-38108625

ABSTRACT

In this article, we discuss the synthesis of eight novel zirconium and hafnium complexes containing amidoxime ligands as potential precursors for atomic layer deposition (ALD). Two amidoximes, viz., (E)-N'-hydroxy-N,N-dimethylacetimidamide (mdaoH) and (Z)-N'-hydroxy-N,N-dimethylpivalimidamide (tdaoH), along with their Zr and Hf homoleptic complexes, Zr(mdao)4 (1), Hf(mdao)4 (2), Zr(tdao)4 (3), and Hf(tdao)4 (4) were prepared. We further synthesized heteroleptic compounds with different physical properties by introducing cyclopentadienyl (Cp) ligand, namely, CpZr(mdao)3 (5), CpHf(mdao)3 (6), CpZr(tdao)3 (7), and CpHf(tdao)3 (8). Thermogravimetric analysis was used for the assessment of the evaporation characteristics of complexes 1, 2, 5, and 6, and it revealed multistep weight losses with high residues. On the other hand, the thermogravimetric analysis curves of complexes 3, 4, 7, and 8 comprising tdao ligands revealed single-step weight losses with moderate residues. Single-crystal X-ray diffraction studies of complexes 1, 3, and 7 showed that all of the complexes have monomeric molecular structures. Complex 7 exhibited a low melting point (75 °C), good volatility, and high thermal stability compared with other complexes. Therefore, an atomic layer deposition process for the growth of ZrO2 was developed by using ZrCp(tdao)3 (7) as a novel precursor.

2.
J Chem Phys ; 160(2)2024 Jan 14.
Article in English | MEDLINE | ID: mdl-38189606

ABSTRACT

Alkoxide precursors have been highlighted for depositing carbon-free films, but their use in Atomic Layer Deposition (ALD) often exhibits a non-saturated growth. This indicates no self-limiting growth due to the chain reaction of hydrolysis or ligand decomposition caused by ß-hydride elimination. In the previous study, we demonstrated that self-limiting growth of ALD can be achieved using our newly developed precursor, hafnium cyclopentadienyl tris(N-ethoxy-2,2-dimethyl propanamido) [HfCp(edpa)3]. To elucidate the growth mechanism and the role of cyclopentadienyl (Cp) ligand in a heteroleptic alkoxide precursor, herein, we compare homoleptic and heteroleptic Hf precursors consisting of N-ethoxy-2,2-dimethyl propanamido (edpa) ligands with and without cyclopentadienyl ligand-hafnium tetrakis(N-ethoxy-2,2-dimethyl propanamido) [Hf(edpa)4] and HfCp(edpa)3. We also investigate the role of a Cp ligand in growth characteristics. By substituting an alkoxide ligand with a Cp ligand, we could modify the surface reaction during ALD, preventing undesired reactions. The last remaining edpa after Hf(edpa)4 adsorption can undergo a hydride elimination reaction, resulting in surface O-H generation. In contrast, Cp remains after the HfCp(edpa)3 adsorption. Accordingly, we observe proper ALD growth with self-limiting properties. Thus, a comparative study of different ligands of the precursors can provide critical clues to the design of alkoxide precursors for obtaining typical ALD growth with a saturation behavior.

3.
Analyst ; 148(6): 1349-1361, 2023 Mar 13.
Article in English | MEDLINE | ID: mdl-36857647

ABSTRACT

An electrochemical immunoassay based on the redox cycling method was presented using vertically paired electrodes (VPEs), which were fabricated using poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as an electrode material and parylene-C as a dielectric layer. For the application to immunoassays, different electrochemical properties of PEDOT:PSS were analyzed for the redox reaction of 3,3',5,5'-tetramethylbenzidine (TMB, the chromogenic substrate for enzyme-immunoassays) at different pH conditions, including the conductivity (σ), electron transfer rate constant (kapp), and double-layer capacitance (Cdl). The influencing factors on the sensitivity of redox cycling based on VPE based on PEDOT:PSS were analyzed for the redox reaction of TMB, such as the electrode gap and number of electrode pairs. Computer simulation was also performed for the redox cycling results based on VPEs, which had limitations in fabrication, such as VPEs with an electrode gap of less than 100 nm and more than five electrode pairs. Finally, the redox cycling based on VPE was applied to the medical diagnosis of human hepatitis-C virus (hHCV) using a commercial ELISA kit. The sensitivity of the redox cycling method for the medical diagnosis of hHCV was compared with conventional assay methods, such as TMB-based chromogenic detection, luminol-based chemiluminescence assay, and a rapid test kit (lateral flow immunoassay).


Subject(s)
Computer Simulation , Humans , Electrodes , Oxidation-Reduction , Immunoassay , Immunoenzyme Techniques
4.
Inorg Chem ; 62(11): 4680-4687, 2023 Mar 20.
Article in English | MEDLINE | ID: mdl-36935645

ABSTRACT

This paper reports the synthesis of three novel titanium complexes containing amidoxime ligands as potential precursors for titanium nitride (TiN) thin films fabricated using atomic layer deposition (ALD). A series of ligands, viz., N'-methoxy-N-methylacetimidamide (mnnoH), N'-ethoxy-N-methylacetimidamide (ennoH), and N'-methoxy-N-methylbenzimidamide (pnnoH), were successfully synthesized and used to produce Ti(mnno)(NMe2)3 (4), Ti(enno)(NMe2)3 (5), and Ti(pnno)(NMe2)3 (6). Thermogravimetric analysis curves of complexes 4-6 revealed a single-step weight loss up to 200 °C. Pyrolysis occurred beyond 200 °C. Among the three new complexes, 5 was liquid at room temperature. Therefore, TiN was synthesized by ALD using Ti(enno)(NMe2)3 (5) as a novel precursor. A TiN thin film was deposited from the Ti(enno)(NMe2)3 (5) precursor and NH3 plasma, and self-limiting growth was achieved by varying the injection/purge duration. TiN thin film growths were observed with a growth per cycle (GPC) of 0.05-0.13 nm·cy-1 at deposition temperatures between 150 and 300 °C, while the measured resistivity was as low as 420 µΩ·cm. The high reactivity of the precursor promotes nucleation, resulting in TiN thin films with smooth, good step coverage and preferentially orientated microstructure.

5.
Analyst ; 147(16): 3783-3794, 2022 Aug 08.
Article in English | MEDLINE | ID: mdl-35876175

ABSTRACT

In this study, parylene-C films from plasma deposition as well as thermal deposition were pyrolyzed to prepare a carbon electrode for application in electrochemical immunoassays. Plasma deposition could prepare parylene-C in a faster deposition rate and more precise control over the thickness in comparison with the conventional thermal deposition. To analyze the influence of the deposition method, the crystal and electronic structures of the pyrolyzed parylene-C films obtained via both deposition methods were compared using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy. For application as a carbon electrode in immunoassays, the electrochemical properties of the pyrolyzed carbon films from two both deposition methods were analyzed, including the double layer capacitance (2.10 µF cm-2 for plasma deposition and 2.20 µF cm-2 for thermal deposition), the apparent electron transfer rate (approximately 1.1 × 10-3 cm s-1 for both methods), and the electrochemical window (approximately -1.0 ∼ 2.1 V for both methods). Finally, the applicability of the pyrolyzed carbon electrode from parylene-C was demonstrated for the diagnosis of human hepatitis-C using various amperometric methods, such as cyclic voltammetry, chronoamperometry, square-wave voltammetry and differential pulse voltammetry.


Subject(s)
Carbon , Pyrolysis , Carbon/chemistry , Electrodes , Humans , Immunoassay , Polymers , Xylenes
6.
Inorg Chem ; 60(23): 17722-17732, 2021 Dec 06.
Article in English | MEDLINE | ID: mdl-34813316

ABSTRACT

This paper describes the synthesis of eight novel zirconium and hafnium complexes containing N-alkoxy carboxamidate-type ligands, as potential precursors for metal oxides and atomic layer deposition (ALD) for HfO2. A series of ligands, viz., N-ethoxy-2,2-dimethylpropanamide (edpaH), N-ethoxy-2-methylpropanamide (empaH), and N-methoxy-2,2-dimethylpropanamide (mdpaH), were used to afford complexes Zr(edpa)4 (1), Hf(edpa)4 (2), Zr(empa)4 (3), Hf(empa)4 (4), Zr(mdpa)4 (5), Hf(mdpa)4 (6), ZrCp(edpa)3 (7), and HfCp(edpa)3 (8). Thermogravimetric analysis curves assessed for the evaporation characteristics of complexes 1-8 revealed single-step weight losses with low residues, except for the mdpa-containing complexes. Single-crystal X-ray diffraction studies of 1, 2, 5, and 6 revealed that all the complexes have monomeric molecular structures, with the central metal ion surrounded by eight oxygen atoms from the four bidentate alkoxyalkoxide ligands. Among the complexes prepared, 8 exhibited a low melting point (64 °C), good volatility (1 Torr at 112 °C), high thermal stability, and excellent endurance over 6 weeks at 120 °C. Therefore, an ALD process for the growth of HfO2 was developed using HfCp(edpa)3 (8) as a novel precursor. Furthermore, the HfO2 film exhibited a low capacitance equivalent oxide thickness of ∼1.5 nm, with Jg as low as ∼3 × 10-4 A/cm2 at Vg -1 V in a metal-insulator-semiconductor capacitor (Au/HfO2/p-Si).

7.
Sensors (Basel) ; 19(24)2019 Dec 16.
Article in English | MEDLINE | ID: mdl-31888286

ABSTRACT

An electrochemical capacitance immunosensor based on an interdigitated wave-shaped micro electrode array (IDWµE) for direct and label-free detection of C-reactive protein (CRP) was reported. A self-assembled monolayer (SAM) of dithiobis (succinimidyl propionate) (DTSP) was used to modify the electrode array for antibody immobilization. The SAM functionalized electrode array was characterized morphologically by atomic force microscopy (AFM) and energy dispersive X-ray spectroscopy (EDX). The nature of gold-sulfur interactions on SAM-treated electrode array was probed by X-ray photoelectron spectroscopy (XPS). The covalent linking of anti-CRP-antibodies onto the SAM modified electrode array was characterized morphologically through AFM, and electrochemically through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The application of phosphate-buffered saline (PBS) and human serum (HS) samples containing different concentrations of CRP in the electrode array caused changes in the electrode interfacial capacitance upon CRP binding. CRP concentrations in PBS and HS were determined quantitatively by measuring the change in capacitance (ΔC) through EIS. The electrode immobilized with anti-CRP-antibodies showed an increase in ΔC with the addition of CRP concentrations over a range of 0.01-10,000 ng mL-1. The electrode showed detection limits of 0.025 ng mL-1 and 0.23 ng mL-1 (S/N = 3) in PBS and HS, respectively. The biosensor showed a good reproducibility (relative standard deviation (RSD), 1.70%), repeatability (RSD, 1.95%), and adequate selectivity in presence of interferents towards CRP detection. The sensor also exhibited a significant storage stability of 2 weeks at 4 °C in 1× PBS.


Subject(s)
C-Reactive Protein/analysis , Electrochemical Techniques/methods , Animals , Antibodies/metabolism , Cattle , Dielectric Spectroscopy , Electric Capacitance , Humans , Hydrogen-Ion Concentration , Microelectrodes , Microscopy, Atomic Force , Photoelectron Spectroscopy , Reproducibility of Results , Serum Albumin, Bovine/metabolism , Succinimides/chemistry
8.
Circ J ; 82(8): 2071-2078, 2018 07 25.
Article in English | MEDLINE | ID: mdl-29681584

ABSTRACT

BACKGROUND: The outcomes of heart failure (HF) with mid-range ejection fraction (HFmrEF) have been rarely studied, and follow-up data on left ventricular ejection fraction (LVEF) are scarse.Methods and Results:Patients were selected from a prospective multicenter registry of patients hospitalized for acute HF and then classified in the improved group if they exhibited %LVEF change ≥5 with follow-up LVEF ≥50%. Follow-up LVEF reported at least 90 days after discharge was used for classification. Of the 3,085 patients with acute HF, 454 were classified in the HFmrEF, and 276 had follow-up data. Of these 276 patients, 34.1% were classified in the improved group. Multivariate analysis revealed that hypertension, higher heart rate, lower serum sodium level, and maintenance therapy with ß-blocker were associated with improved LVEF. The survival rate was significantly higher in the improved group than in the other groups. Young age and maintenance therapy with renin-angiotensin system blockers or aldosterone antagonists were significantly associated with better survival in HFmrEF. CONCLUSIONS: One-third of HFmrEF patients showed improved LVEF; moreover, the survival rate in the improved group was higher than the other groups. Renin-angiotensin system blockers and aldosterone antagonists could improve the survival of HFmrEF patients.


Subject(s)
Heart Failure/mortality , Stroke Volume/physiology , Acute Disease , Aged , Aged, 80 and over , Follow-Up Studies , Heart Failure/diagnosis , Heart Failure/drug therapy , Heart Failure/epidemiology , Humans , Middle Aged , Mineralocorticoid Receptor Antagonists/therapeutic use , Prognosis , Registries , Renin-Angiotensin System/drug effects , Risk Factors , Survival Analysis , Treatment Outcome
9.
Sensors (Basel) ; 18(11)2018 Nov 12.
Article in English | MEDLINE | ID: mdl-30424510

ABSTRACT

We report the electrical characteristics and pH responses of a Si-nanonet ion-sensitive field-effect transistor with ultra-thin parylene-H as a gate sensing membrane. The fabricated device shows excellent DC characteristics: a low subthreshold swing of 85 mV/dec, a high current on/off ratio of ~107 and a low gate leakage current of ~10-10 A. The low interface trap density of 1.04 × 1012 cm-2 and high field-effect mobility of 510 cm²V-1s-1 were obtained. The pH responses of the devices were evaluated in various pH buffer solutions. A high pH sensitivity of 48.1 ± 0.5 mV/pH with a device-to-device variation of ~6.1% was achieved. From the low-frequency noise characterization, the signal-to-noise ratio was extracted as high as ~3400 A/A with the lowest noise equivalent pH value of ~0.002 pH. These excellent intrinsic electrical and pH sensing performances suggest that parylene-H can be promising as a sensing membrane in an ISFET-based biosensor platform.

10.
Echocardiography ; 34(4): 511-522, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28332215

ABSTRACT

BACKGROUND: The aim of this study was to determine the capability of real time three-dimensional echocardiography (RT3DE) and two-dimensional (2D) multilayer speckle tracking echocardiography (MSTE) for evaluation of early myocardial dysfunction triggered by increased left ventricular (LV) wall thickness in severe aortic stenosis (AS) with normal LV ejection fraction (EF≥55%). METHODS: Conventional, RT3D STE and 2D MSTE were performed in 45 patients (mean 68.9±9.0 years) with severe AS (aortic valve area <1 cm2 , aortic velocity Vmax >4 m/s or mean PG >40 mm Hg) and normal left ventricular ejection fraction (LVEF) without overt coronary artery disease and in 18 age-, sex-matched healthy controls. Global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) were calculated using RT3DE and MSTE. RESULTS: The severe AS group had lower 3D GLS, GRS, GAS and 2D epicardium, and mid-wall and endocardium GLS compared to healthy controls. In MSTE analysis, 2D LS and CS values decreased from the endocardial layer toward the epicardial layer. Severe AS patients with increased LV wall thickness had lower 3D GLS and 2D epicardium, and mid-wall and endocardium GLS compared with severe AS patients without LV wall thickening. GLS on RT3D STE was correlated with GLS on 2D MSTE, left ventricular mass index, LVEF, left atrial volume index, and lnNT-proBNP. CONCLUSION: RT3DE and 2D MSTE can be used to identify subtle contractile dysfunction triggered by increased LV wall thickness in severe AS with normal LVEF. Therefore, RT3D STE and 2D MSTE may provide additional information that can facilitate decision-making regarding severe AS patients with increased LV wall thickness and normal LV function.


Subject(s)
Aortic Valve Stenosis/physiopathology , Echocardiography/methods , Heart Ventricles/diagnostic imaging , Heart/physiopathology , Ventricular Function, Left/physiology , Aged , Echocardiography, Three-Dimensional/methods , Female , Humans , Male , Reproducibility of Results
11.
Heart Vessels ; 31(8): 1277-84, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26266634

ABSTRACT

Because of frequent tuberculosis in patients with Takayasu arteritis (TA), a possible relationship between TA and tuberculosis has been proposed. However, there are no studies to date that have examined clinical manifestations in patients diagnosed with TA with or without tuberculosis. Two hundred sixty-seven patients were diagnosed with TA according to the 1990 American College of Rheumatology criteria between September 1994 and April 2014. Patients with TA were classified into groups with or without tuberculosis. Among the 267 patients with TA studied, 47 patients (17.7 %) who had a history of previous treatment of tuberculosis (34 patients), concurrent diagnosis of tuberculosis with TA (10 patients), or diagnosis of tuberculosis during the follow-up period for TA (3 patients) were included in the group with tuberculosis. The group with tuberculosis comprised of 33 patients (70.2 %) with pulmonary tuberculosis, 12 patients (25.5 %) with tuberculous lymphadenitis, and 2 patients (4.3 %) with tuberculosis of the skin and colon, respectively. Comorbid disease and patients' signs and symptoms were not significantly different between TA patients with and without tuberculosis. Additionally, the site of disease involvement in angiographic findings and distribution of angiographic type were similar between the two groups. In conclusion, tuberculosis including tuberculous lymphadenitis was frequently observed in patients with TA. Clinical features and angiographic findings in TA were not different according to the presence or absence of concomitant tuberculosis.


Subject(s)
Takayasu Arteritis/complications , Tuberculosis/diagnostic imaging , Tuberculosis/epidemiology , Adult , Comorbidity , Computed Tomography Angiography , Female , Humans , Magnetic Resonance Angiography , Male , Mycobacterium tuberculosis , Republic of Korea/epidemiology , Takayasu Arteritis/microbiology , Young Adult
12.
Sensors (Basel) ; 16(12)2016 Dec 05.
Article in English | MEDLINE | ID: mdl-27929401

ABSTRACT

Electrical cell-substrate impedance sensing is increasingly being used for label-free and real-time monitoring of changes in cell morphology and number during cell growth, drug screening, and differentiation. In this study, we evaluated the feasibility of using ECIS to monitor C2C12 myoblast differentiation using a fabricated indium tin oxide (ITO) electrode-based chip. C2C12 myoblast differentiation on the ITO electrode was validated based on decreases in the mRNA level of MyoD and increases in the mRNA levels of myogenin and myosin heavy chain (MHC). Additionally, MHC expression and morphological changes in myoblasts differentiated on the ITO electrode were comparable to those in cells in the control culture dish. From the monitoring the integration of the resistance change at 21.5 kHz, the cell differentiation was label-free and real-time detectable in 30 h of differentiation (p < 0.05).


Subject(s)
Cell Differentiation , Electric Impedance , Myoblasts/cytology , Tin Compounds/pharmacology , Animals , Cell Count , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Cell Shape/drug effects , Cells, Cultured , Electrodes , Extracellular Matrix/metabolism , Mice , Microscopy, Atomic Force , Muscle Proteins/genetics , Muscle Proteins/metabolism , Myoblasts/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism
13.
Ann Hum Genet ; 79(2): 99-107, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25644864

ABSTRACT

Hereditary transthyretin (TTR)-related amyloidosis (ATTR) seems to be a rare autosomal-dominant inherited form of systemic amyloidosis. Studies indicate considerable heterogeneity in the disease's presentation and genotype; however, there is little data from Korea, where the prevalence of hereditary ATTR is very low. In this study, we investigated the phenotypic and genotypic spectra of hereditary ATTR in Korea. Direct sequencing analysis was performed to detect TTR gene mutations in amyloidosis patients whose results of TTR immunohistochemical staining were positive or equivocal. Clinical presentation was categorized as exclusively cardiac, exclusively neurologic, or mixed phenotype. Of 12 genetic tests performed, seven were positive for TTR mutations. D58A (c.173A>C) was the most common mutation in this study (57%, 4/7). The majority of those patients with hereditary ATTR had the mixed phenotype (86%, 6/7). The patients with D58A mutation had older ages of disease onset (median, 61 years vs. 42 years; P = 0.08), and a higher incidence of gastrointestinal involvement (75% vs. 0%; P = 0.03) than those with other identified TTR mutations. A significant male predominance was also noted in this study (P = 0.01).


Subject(s)
Amyloid Neuropathies, Familial/genetics , DNA Mutational Analysis , Mutation, Missense , Adult , Amino Acid Substitution , Female , Humans , Male , Middle Aged , Republic of Korea
14.
Circ J ; 79(7): 1575-84, 2015.
Article in English | MEDLINE | ID: mdl-25854713

ABSTRACT

BACKGROUND: Relative apical sparing pattern of longitudinal strain (RapSP-LS) was suggested in advanced cardiac amyloidosis (CA). It is unclear whether it is present in less advanced CA. METHODS AND RESULTS: Patients with presumptive diagnosis of CA and mean left ventricular wall thickness (LVWT) ≤14 mm were recruited. Apart from RapSP-LS visually identified, relative apical longitudinal strain index (RapLSI) was defined as [average apical LS/(average basal LS+average mid-ventricle LS)]. Among 119 patients included, 47 were finally diagnosed with CA. RapLSI was higher in the CA group compared to other causes of increased mean LVWT (P<0.001), but with a significant range of overlap noted. In contrast, RapSP-LS visually assessed was noted in most CA patients (31/47, 66.0%) except in those with preserved LV ejection fraction, normal LVWT, and mildly decreased global LS, suggesting least advanced CA. On multivariate analysis of the added diagnostic role of RapSP-LS or RapLSI on top of clinical, electrocardiographic, and conventional echocardiographic parameters, addition of RapLSI produced only borderline increase in area under the curve of the multivariate model (P=0.05), whereas addition of RapSP-LS significantly increased it (P<0.001). CONCLUSIONS: Visual identification of RapSP-LS is useful in terms of added diagnostic value compared with quantitative calculation of RapLSI. Its clinical application, however, should be used with caution in patients with less advanced CA.


Subject(s)
Amyloidosis/diagnostic imaging , Heart Diseases/diagnostic imaging , Aged , Amyloidosis/physiopathology , Echocardiography/methods , Female , Heart Diseases/physiopathology , Heart Ventricles/diagnostic imaging , Heart Ventricles/physiopathology , Humans , Male , Middle Aged
15.
Radiology ; 270(1): 74-81, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24009351

ABSTRACT

PURPOSE: To evaluate coronary arterial lesions and to assess their correlation with clinical findings in patients with Takayasu arteritis (TA) by using coronary computed tomographic (CT) angiography. MATERIALS AND METHODS: This retrospective study was approved by the hospital internal review board, and informed consent was waived. A total of 111 consecutive patients with TA (97 female, 14 male; mean age, 44 years ± 13.8 [standard deviation]; age range, 14-74 years) underwent CT angiography of the coronary arteries and aorta with 128-section dual-source CT. CT angiographic, clinical, and laboratory findings of each patient were retrospectively reviewed. Statistical differences between coronary CT angiographic findings and clinical parameters were examined with univariate analysis. RESULTS: Of 111 patients, 32 (28.8%) had cardiac symptoms and the remaining 79 (71.2%) had no cardiac symptoms. Fifty-nine patients (53.2%) had coronary arterial lesions at coronary CT angiography. Three main radiologic features were detected: coronary ostial stenosis (n = 31, 28.0%), nonostial coronary arterial stenosis (n = 41, 36.9%), and coronary aneurysm (n = 9, 8.1%). Coronary artery ostial or luminal stenosis of 50% or more or coronary aneurysms were observed in 26 (23.4%) patients with TA. Patients with coronary arterial abnormalities at coronary CT angiography had higher incidences of hypertension (P = .02), were older at the time of CT (P = .01), and had longer duration of TA (P = .02) than those without coronary artery abnormalities. The presence of cardiac symptoms, disease activity, and other comorbidities was not associated with differences in coronary artery involvement. CONCLUSION: In patients with TA, there is a high prevalence of coronary arterial abnormalities at coronary CT angiography, regardless of disease activity or symptoms. Thus, coronary CT angiography may add information on coronary artery lesions in patients with TA.


Subject(s)
Coronary Angiography/methods , Takayasu Arteritis/diagnostic imaging , Tomography, X-Ray Computed/methods , Adolescent , Adult , Aged , Aorta, Thoracic/diagnostic imaging , Aorta, Thoracic/pathology , Cardiac-Gated Imaging Techniques , Contrast Media , Coronary Vessels/diagnostic imaging , Coronary Vessels/pathology , Female , Humans , Iopamidol/analogs & derivatives , Male , Middle Aged , Retrospective Studies , Takayasu Arteritis/pathology
16.
J Korean Med Sci ; 29(1): 137-40, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24431918

ABSTRACT

Left ventricular assist device (LVAD) is a good treatment option for the patients ineligible for cardiac transplantation. Several studies have demonstrated that a ventricular assist device improves the quality of life and prognosis of the patients with end-stage heart failure. A 75-yr-old man debilitated with New York Heart Association (NYHA) functional class III-IV due to severe left ventricular systolic dysfunction received LVAD implantation as a destination therapy. The patient was discharged with improved functional status (NYHA functional class II) after appropriate cardiac rehabilitation and education about how to manage the device and potential emergency situations. This is the first case of successful continuous-flow LVAD implantation as a destination therapy in Korea.


Subject(s)
Heart Failure/surgery , Heart-Assist Devices , Ventricular Dysfunction, Left/surgery , Aged , Dyspnea , Echocardiography , Humans , Male , Prosthesis Implantation , Quality of Life , Republic of Korea , Treatment Outcome
17.
J Korean Med Sci ; 29(6): 776-81, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24932077

ABSTRACT

Right-sided infective endocarditis (RIE) occurs predominantly in intravenous drug users in western countries, and it has a relatively good prognosis. Clinical features and prognosis of RIE occurring in non-drug users are not well known. We investigated the clinical findings of RIE in non-drug users. We retrospectively reviewed 345 cases diagnosed with IE. Cases with RIE or left-sided infective endocarditis (LIE) defined by the vegetation site were included and cases having no vegetation or both-side vegetation were excluded. Clinical findings and in-hospital outcome of RIE were compared to those of LIE. Among the 245 cases, 39 (16%) cases had RIE and 206 (84%) cases had LIE. RIE patients were younger (40 ± 19 yr vs 50 ± 18 yr, P=0.004), and had a higher incidence of congenital heart disease (CHD) (36% vs 13%, P<0.001) and central venous catheter (CVC) (21% vs 4%, P=0.001) compared to LIE patients. A large vegetation was more common in RIE (33% vs 9%, P<0.001). Staphylococcus aureus was the most common cause of RIE, while Streptococcus viridans were the most common cause of LIE. In-hospital mortality and cardiac surgery were not different between the two groups. CHD and use of CVC were common in non-drug users with RIE. The short-term clinical outcome of RIE is not different from that of LIE.


Subject(s)
Endocarditis, Bacterial/diagnosis , Adult , Aged , Central Venous Catheters/microbiology , Echocardiography , Endocarditis, Bacterial/microbiology , Endocarditis, Bacterial/mortality , Female , Heart Defects, Congenital/complications , Heart Defects, Congenital/epidemiology , Hospital Mortality , Humans , Incidence , Male , Middle Aged , Prognosis , Retrospective Studies , Staphylococcus aureus/isolation & purification , Viridans Streptococci/isolation & purification , Young Adult
18.
Food Sci Biotechnol ; 33(3): 711-720, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38274180

ABSTRACT

In this study, we investigated the effect of cycloastragenol (CAG), a triterpenoid isolated from Astragalus membranaceus roots, on regulating the adipogenesis and fat accumulation in vitro and in vivo. During the adipogenesis of 3T3-L1 cells, CAG inhibited lipid accumulation and the expression of key adipogenic factors, proliferator-activated receptor γ (PPARγ) and CCAAT enhancer binding protein α (C/EBPα) and increased the expression of Gli1, a key mediator in Hedgehog (Hh) signaling. In HFD-induced animal experiment, CAG significantly reduced body weight gain without affecting brown fat weight. In addition, CAG regulated the expression of PPARγ, C/EBPα, and Gli1 in visceral white adipose tissue (vWAT). We also confirmed the inhibitory effect of CAG on specifically targeting white adipose tissue (WAT) formation in stromal vascular fraction (SVF) cell differentiation. Taken together, these results suggest that CAG may be a potent phytochemical preventing adipogenesis and obesity via Hh signaling. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01403-0.

19.
Food Sci Biotechnol ; 33(1): 171-180, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38186621

ABSTRACT

Following 3R (reduction, refinement, and replacement) principles, we employed the rat liver S9 fraction to mimic liver metabolism of curcumol having high in vitro IC50 on cancer cells. In HCT116 and HT29 colon cancer cells, the metabolites of curcumol by S9 fraction exerted more enhanced activity in inducing cell cycle arrest and apoptosis via regulating the expression of cyclin D1, CDK1, p21, PARP and Bcl-2 than curcumol. In addition, oral administration of curcumol at 4 mg/kg BW significantly suppressed the development of colon tumor induced by azoxymethane/dextran sulfate sodium, and induced cell cycle arrest and apoptosis in tumor tissues. In mass analysis, curcumenol and curzerene were identified as the metabolites of curcumol by S9 fraction metabolism. Taken together, curcumol metabolites showed the enhanced suppressive effect on colon cancer, suggesting that S9 fraction can be considered as simple, fast, and bio-mimicking platform for the screening of chemical libraries on different chronic diseases.

20.
Opt Express ; 21(3): 3287-97, 2013 Feb 11.
Article in English | MEDLINE | ID: mdl-23481788

ABSTRACT

A series of single-phased emission-tunable Na(0.34)Ca(0.66)Al(1.66)Si(2.34)O(8):Eu(2+),Mn(2+) phosphors were successfully synthesized by a wet-chemical synthesis method. Photoluminescence excitation (PLE) spectra indicate that the phosphor can be efficiently excited by UV radiation from 250 to 420 nm. Also, NCASO:Eu(2+),Mn(2+) phosphor exhibit a broad blue emission band at 440 nm and an orange emission band at 570 nm, which originate from Eu(2+) and Mn(2+) ions, respectively. Therefore, overall emission color can be tuned from blue to white by increasing the concentration of Mn(2+) ions in the host lattice utilizing energy transfer from Eu(2+) to Mn(2+) ions. This energy transfer phenomenon was demonstrated to be a resonant type through dipole-dipole interaction determined with the help of PL spectra, decay time measurement, and energy transfer efficiency of the phosphor. These results indicate that NCASO:Eu(2+),Mn(2+) can be a promising single-phased white-emitting phosphor for white-light UV LEDs.


Subject(s)
Color , Lighting/instrumentation , Refractometry/instrumentation , Semiconductors , Equipment Design , Equipment Failure Analysis , Ultraviolet Rays
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