oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 22 )

2018 ( 36 )

2017 ( 16 )

2016 ( 44 )

Custom range...

Search Results: 1 - 10 of 10081 matches for " Jeon Woo-Young "
All listed articles are free for downloading (OA Articles)
Page 1 /10081
Display every page Item
A case of successful survival from ventricular free wall micro-rupture without surgery  [PDF]
Jae-Bin Seo, Ki-Hyun Jeon, Jin-Hyun Park, Sang-Hyun Kim, Joo-Hee Zo, Myung-A Kim, Woo-Young Chung
World Journal of Cardiovascular Diseases (WJCD) , 2013, DOI: 10.4236/wjcd.2013.32029
Abstract:

We report a case of successful survival from ventricular free wall rupture without surgery, which was not overt rupture but micro-rupture. The patient was diagnosed with acute myocardial infarction (AMI) and underwent primary percutaneous coronary intervention (PCI). Myocardial blood leakage could be detected on transthoracic echocardiography with intravenous infusion of contrast dye 3 days after PCI. This examination revealed that there was not overt perforation but diffuse fissure. Because of his critical condition, he was treated conservatively without surgery. Nevertheless, he survived eventually.

Dianthus superbus fructus suppresses airway inflammation by downregulating of inducible nitric oxide synthase in an ovalbumin-induced murine model of asthma
Shin In-Sik,Lee Mee-Young,Ha Hyekyung,Jeon Woo-Young
Journal of Inflammation , 2012, DOI: 10.1186/1476-9255-9-41
Abstract: Background Dianthus superbus has long been used as a herbal medicine in Asia and as an anti-inflammatory agent. In this study, we evaluated the anti-inflammatory effects of Dianthus superbus fructus ethanolic extract (DSE) on Th2-type cytokines, eosinophil infiltration, and other factors in an ovalbumin (OVA)-induced murine asthma model. To study the possible mechanism of the anti-inflammatory effect of DSE, we also evaluated the expression of inducible nitric oxide synthase (iNOS) in the respiratory tract. Methods Mice were sensitized on days 0 and 14 by intraperitoneal injection of OVA. On days 21, 22 and 23 after initial sensitization, mice received an airway challenge with OVA for 1 h using an ultrasonic nebulizer. DSE was applied 1 h prior to OVA challenge. Mice were administered DSE orally at doses of 100 mg/kg or 200 mg/kg once daily from day 18 to 23. Bronchoalveolar lavage fluid (BALF) was collected 48 h after the final OVA challenge. Levels of interleukin (IL)-4, IL-13 and eotaxin in BALF were measured using enzyme-linked immunosorbent assays (ELISAs). Lung tissue sections were stained with hematoxylin and eosin for assessment of cell infiltration and mucus production with periodic acid shift staining, in conjunction with ELISA and western blot analyses for iNOS expression. Results DSE significantly reduced the levels of IL-4, IL-13, eotaxin, and immunoglobulin (Ig) E, number of inflammatory cells in BALF, and inflammatory cell infiltration and mucus production in the respiratory tract. DSE also attenuated the overexpression of iNOS protein induced by OVA challenge. Conclusion Our results suggest that DSE effectively protects against allergic airway inflammation by downregulating of iNOS expression and that DSE has potential as a therapeutic agent for allergic asthma.
Protective Effects of the Traditional Herbal Formula Oryeongsan Water Extract on Ethanol-Induced Acute Gastric Mucosal Injury in Rats
Woo-Young Jeon,Mee-Young Lee,In-Sik Shin,Hye-Sun Lim,Hyeun-Kyoo Shin
Evidence-Based Complementary and Alternative Medicine , 2012, DOI: 10.1155/2012/438191
Abstract: This study was performed to evaluate the protective effect and safety of Oryeongsan water extract (OSWE) on ethanol-induced acute gastric mucosal injury and an acute toxicity study in rats. Acute gastric lesions were induced via intragastric oral administration of absolute ethanol at a dose of 5 mL/kg. OSWE (100 and 200 mg/kg) was administered to rats 2 h prior to the oral administration of absolute ethanol. The stomach of animal models was opened and gastric mucosal lesions were examined. Gastric mucosal injuries were evaluated by measuring the levels of malondialdehyde (MDA), glutathione (GSH), and the activity of antioxidant enzymes. In the acute toxicity study, no adverse effects of OSWE were observed at doses up to 2000 mg/kg/day. Administration of OSWE reduced the damage by conditioning the gastric mucosa against ethanol-induced acute gastric injury, which included hemorrhage, hyperemia, and loss of epithelial cells. The level of MDA was reduced in OSWE-treated groups compared with the ethanol-induced group. Moreover, the level of GSH and the activity of antioxidant enzymes were significantly increased in the OSWE-treated groups. Our findings suggest that OSWE has a protective effect on the gastric mucosa against ethanol-induced acute gastric injury via the upregulation of antioxidant enzymes.
Cyclic Bis-1,3-dialkylpyridiniums from the Sponge Haliclona sp.
Yoonyeong Lee,Kyoung Hwa Jang,Ju-eun Jeon,Woo-Young Yang,Chung J. Sim,Ki-Bong Oh,Jongheon Shin
Marine Drugs , 2012, DOI: 10.3390/md10092126
Abstract: Eight novel cyclic bis-1,3-dialkylpyridiniums, as well as two known compounds from the cyclostellettamine class, were isolated from the sponge Haliclona sp. from Korea. Structures of these novel compounds were determined using combined NMR and FAB-MS/MS analyses. Several of these compounds exhibited moderate cytotoxic and antibacterial activities against A549 cell-line and Gram-positive strains, respectively. The structure-activity relationships of cyclostellettamines are discussed based on their bioactivities.
Presenilins are required for maintenance of neural stem cells in the developing brain
Woo-Young Kim, Jie Shen
Molecular Neurodegeneration , 2008, DOI: 10.1186/1750-1326-3-2
Abstract: During mammalian neural development, neural progenitor cells (NPCs) divide and populate the progenitor pool in the ventricular zone (VZ) of the developing telencephalon [1]. There are two phases of neurogenesis. The first phase spans from embryonic day 8.5 (E8.5) to 10.5, during which neural progenitor population expands. The second phase commences around E11.5, reaches peak by E15.5, and then diminishes by E17.5, generating most of the cortical neurons through eleven cell cycles [2-6]. During the first phase, neural progenitor cells are columnar, connecting the pial surface and the apical surface, and predominantly undergo symmetric cell division to expand rapidly the self-renewal founder progenitor cells [6,7]. During the second phase, neural progenitors in the ventricular zone predominantly undergo asymmetric cell division to generate self-renewal daughter progenitor cells that remain in the cell cycle and committed postmitotic neural precursor daughter cells that will ultimately differentiate into neurons or glia [3,7-10]. Notch receptors are required for neural progenitor cell proliferation [11-13]. In the cell cycle of this asymmetric cell division, at the transition from S phase to M phase, the dividing neural progenitor cells displace their nuclei and subsequently migrate from the basal membrane to the apical surface of the neuroepithelium, a phenomenon termed interkinetic nuclear migration (INM) [14,15].Presenilin-1 (PS1) and presenilin-2 (PS2) are the major causative genes of familiar Alzheimer disease (FAD) [16]. Presenilin (PS) is an essential component of the γ-secretase complex, and Notch is one of the physiological substrates of γ-secretase [17]. Notch is one of the most important regulators of neural development in organisms from insects to mammals [18-20]. During mammalian neural development, activation of the Notch signaling pathway is involved in the maintenance of neural progenitor identity and the decision of cell fate [21]. Presenilin is requir
Immediate impact of exercise on arterial stiffness in humans  [PDF]
Jae-Bin Seo, Woo-Young Chung, Sang-Hyun Kim, Myung-A Kim, Joo-Hee Zo
World Journal of Cardiovascular Diseases (WJCD) , 2013, DOI: 10.4236/wjcd.2013.31009
Abstract:

Background and objectives: Increased arterial stiffness is an accepted cardiovascular risk factor. Several studies have shown that regular exercise is associated with reduced arterial stiffness. However, the acute effect is not well known. The aim of this study was to evaluate the immediate impact of exercise on arterial stiffness measured by pulse wave velocity (PWV). Subjects and Methods: Data from 100 consecutive patients who underwent graded maximal aerobic exercise test and pulse wave velocity study due to chest pain were analyzed. Results: With respect to brachial-ankle pulse wave velocity (baPWV), it decreased after the exercise test (before vs. after; 1420 ± 260 vs. 1358 ± 245, 1428 ± 255, vs. 1360 ±239 cm/sec; left and right, respectively). Upper extremity systolic blood pressure did not change from baseline. However, upper extremity diastolic blood pressure increased slightly. In addition, lower extremity blood pressure decreased in both systolic and diastolic phases. In both normotensives and hypertensives, baPWV decreased after exercise test. Conclusion: Exercise immediately decreases arterial stiffness.

Calculation of DOS-Dependent Channel Potentials in FETs in the Saturation Condition
Woo-young So,David V. Lang,Arthur P. Ramirez
Physics , 2007,
Abstract: We calculated functions for the potential, Vch, in the channel of a field effect transistor with various densities of the localized states (DOS) by using a device simulator. In the saturation condition, Vch is found to fit satisfactorily to the analytical function, Vch(y)=Vg(1-(1-y/L) k), where Vg is the gate bias, y is the position along the channel, and L is the channel length. The power k, which depends on the DOS, ranges from 0 to 0.5 even with an extensive variation of DOS. As a result, the total induced charge density in the saturation condition can be expressed a way similar to the linear condition by introducing a correction factor, alpha, ranging between 0.65 and 1.0.
Effects of Spiral Arms on Star Formation in Nuclear Rings of Barred-spiral Galaxies
Woo-Young Seo,Woong-Tae Kim
Physics , 2014, DOI: 10.1088/0004-637X/792/1/47
Abstract: We use hydrodynamic simulations to study the effect of spiral arms on the star formation rate (SFR) occurring in nuclear rings of barred-spiral galaxies. We find that spiral arms can be an efficient means of gas transport from the outskirts to the central parts, provided that the arms are rotating slower than the bar. While the ring star formation in models with no-arm or corotating arms is active only during about the bar growth phase, arm-driven gas accretion makes the ring star formation both enhanced and prolonged significantly in models with slow-rotating arms. The arm-enhanced SFR is larger by a factor of ~ 3-20 than in the no-arm model, with larger values corresponding to stronger and slower arms. Arm-induced mass inflows also make dust lanes stronger. Nuclear rings in slow-arm models are ~ 45% larger than in the no-arm counterparts. Star clusters that form in a nuclear ring exhibit an age gradient in the azimuthal direction only when the SFR is small, whereas no noticeable age gradient is found in the radial direction for models with arm-induced star formation.
Gaseous Structures in Barred Galaxies: Effects of the Bar Strength
Woong-Tae Kim,Woo-Young Seo,Yonghwi Kim
Physics , 2012, DOI: 10.1088/0004-637X/758/1/14
Abstract: Using hydrodynamic simulations, we investigate the physical properties of gaseous substructures in barred galaxies and their relationships with the bar strength. The gaseous medium is assumed to be isothermal and unmagnetized. The bar potential is modeled as a Ferrers prolate with index n. To explore situations with differing bar strength, we vary the bar mass fbar relative to the spheroidal component as well as its aspect ratio. We derive expressions as functions of fbar and the aspect ratio for the bar strength Qb and the radius r(Qb) where the maximum bar torque occurs. When applied to observations, these expressions suggest that bars in real galaxies are most likely to have fbar=0.25-0.5 and n<1. Dust lanes approximately follow one of x1-orbits and tend to be more straight under a stronger and more elongated bar, but are insensitive to the presence of self-gravity. A nuclear ring of a conventional x2 type forms only when the bar is not so massive or elongated. The radius of an x2-type ring is generally smaller than the inner Lindblad resonance, decreases systematically with increasing Qb, and slightly larger when self-gravity is included. This evidences that the ring position is not determined by the resonance but by the amount of angular momentum loss at dust-lane shocks. Nuclear spirals exist only when the ring is of the x2-type and sufficiently large in size. Unlike the other features, nuclear spirals are transient in that they start out as being tightly-wound and weak, and then due to the nonlinear effect unwind and become stronger until turning into shocks, with an unwinding rate higher for larger Qb. The mass inflow rate to the galaxy center is found to be less than 0.01 Msun/yr for models with Qb<0.2, while becoming larger than 0.1 Msun/yr when Qb>0.2 and self-gravity is included.
Star Formation in Nuclear Rings of Barred Galaxies
Woo-Young Seo,Woong-Tae Kim
Physics , 2013, DOI: 10.1088/0004-637X/769/2/100
Abstract: Nuclear rings in barred galaxies are sites of active star formation. We use hydrodynamic simulations to study temporal and spatial behavior of star formation occurring in nuclear rings of barred galaxies where radial gas inflows are triggered solely by a bar potential. The star formation recipes include a density threshold, an efficiency, conversion of gas to star particles, and delayed momentum feedback via supernova explosions. We find that star formation rate (SFR) in a nuclear ring is roughly equal to the mass inflow rate to the ring, while it has a weak dependence on the total gas mass in the ring. The SFR typically exhibits a strong primary burst followed by weak secondary bursts before declining to very small values. The primary burst is associated with the rapid gas infall to the ring due to the bar growth, while the secondary bursts are caused by re-infall of the ejected gas from the primary burst. While star formation in observed rings persists episodically over a few Gyr, the duration of active star formation in our models lasts for only about a half of the bar growth time, suggesting that the bar potential alone is unlikely responsible for gas supply to the rings. When the SFR is low, most star formation occurs at the contact points between the ring and the dust lanes, leading to an azimuthal age gradient of young star clusters. When the SFR is large, on the other hand, star formation is randomly distributed over the whole circumference of the ring, resulting in no apparent azimuthal age gradient. Since the ring shrinks in size with time, star clusters also exhibit a radial age gradient, with younger clusters found closer to the ring. The cluster mass function is well described by a power law, with a slope depending on the SFR. Giant gas clouds in the rings have supersonic internal velocity dispersions and are gravitationally bound.
Page 1 /10081
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.